Endovascular system for arresting the heart

Devices and methods are provided for temporarily inducing cardioplegic arrest in the heart of a patient and for establishing cardiopulmonary bypass in order to facilitate surgical procedures on the heart and its related blood vessels. Specifically, a catheter based system is provided for isolating the heart and coronary blood vessels of a patient from the remainder of the arterial system and for infusing a cardioplegic agent into the patient's coronary arteries to induce cardioplegic arrest in the heart. The system includes an endoaortic partitioning catheter having an expandable balloon at its distal end which is expanded within the ascending aorta to occlude the aortic lumen between the coronary ostia and the brachiocephalic artery. Means for centering the catheter tip within the ascending aorta include specially curved shaft configurations, eccentric or shaped occlusion balloons and a steerable catheter tip, which may be used separately or in combination. The shaft of the catheter may have a coaxial or multilumen construction. The catheter may further include piezoelectric pressure transducers at the distal tip of the catheter and within the occlusion balloon. Means to facilitate nonfluoroscopic placement of the catheter include fiberoptic transillumination of the aorta and a secondary balloon at the distal tip of the catheter for atraumatically contacting the aortic valve. The system further includes a dual purpose arterial bypass cannula and introducer sheath for introducing the catheter into a peripheral artery of the patient.

FIELD OF THE INVENTION 
The present invention relates generally to devices and methods for 
temporarily inducing cardioplegic arrest in the heart of a patient and for 
establishing cardiopulmonary bypass in order to facilitate surgical 
procedures on the heart and its related blood vessels. More particularly, 
it relates to a catheter based system for isolating the heart and coronary 
blood vessels of a patient from the remainder of the arterial system and 
for infusing a cardioplegic agent into the patient's coronary arteries to 
induce cardioplegic arrest in the heart. 
BACKGROUND OF THE INVENTION 
Various cardiovascular, neurosurgical, pulmonary and other interventional 
procedures, including repair or replacement of aortic, mitral and other 
heart valves, repair of septal defects, congenital defect repairs, 
pulmonary thrombectomy, coronary artery bypass grafting, angioplasty, 
atherectomy, treatment of aneurysms, electrophysiological mapping and 
ablation, and neurovascular procedures, may require general anesthesia, 
cardiopulmonary bypass, and arrest of cardiac function. In such 
procedures, the heart and coronary blood vessels must be isolated from the 
remainder of the circulatory system. This serves several purposes. First, 
such isolation facilitates infusion of cardioplegic fluid into the 
coronary arteries in order to perfuse the myocardium and thereby arrest 
cardiac function, without allowing the cardioplegic fluid to be 
distributed elsewhere in the patient's circulatory system. Second, such 
isolation facilitates the use of a cardiopulmonary bypass system to 
maintain circulation of oxygenated blood throughout the circulatory system 
while the heart is stopped, without allowing such blood to reach the 
coronary arteries which might resuscitate the heart. Third, in cardiac 
procedures, such isolation creates a working space into which the flow of 
blood and other fluids can be controlled or prevented so as to create an 
optimum surgical environment. 
Using current techniques, isolation of the heart and coronary blood vessels 
is accomplished by placing a mechanical cross-clamp externally on the 
ascending aorta downstream of the ostia of the coronary arteries, but 
upstream of the brachiocephalic artery, so as to allow oxygenated blood 
from the cardiopulmonary bypass system to reach the arms, neck, head, and 
remainder of the body. A catheter is then inserted directly into the 
ascending aorta between the cross-clamp and the aortic valve, and 
cardioplegic fluid is infused through the catheter into the ascending 
aorta and coronary arteries to perfuse the myocardium and/or to vent or 
decompress the heart. An additional catheter may be introduced into the 
coronary sinus for retrograde perfusion of the myocardium with 
cardioplegic fluid. In addition, the myocardium is usually cooled by 
irrigating with cold saline solution and/or application of ice or cold 
packs to the myocardial tissue. Cardiac contractions will then cease. 
Known techniques for performing major surgeries such as coronary artery 
bypass grafting and heart valve repair and replacement have generally 
required open access to the thoracic cavity through a large open wound, 
known as a thoracotomy. Typically, the sternum is cut longitudinally (a 
median sternotomy), providing access between opposing halves of the 
anterior portion of the rib cage to the heart and other thoracic vessels 
and organs. An alternate method of entering the chest is via a lateral 
thoracotomy, in which an incision, typically 10 cm to 20 cm in length, is 
made between two ribs. A portion of one or more ribs may be permanently 
removed to optimize access. 
In procedures requiring a median sternotomy or other type of thoracotomy, 
the ascending aorta is readily accessible for placement of an external 
cross-clamp through this large opening in the chest. However, such surgery 
often entails weeks of hospitalization and months of recuperation time, in 
addition to the pain and trauma suffered by the patient. Moreover, while 
the average mortality rate associated with this type of procedure is about 
two to fifteen per cent for first-time surgery, mortality and morbidity 
are significantly increased for reoperation. Further, significant 
complications may result from such procedures. For example, application of 
an external cross-clamp to a calcified or atheromatous aorta may cause the 
release of emboli into the brachiocephalic, carotid or subclavian arteries 
with serious consequences such as strokes. In up to 6% of the open-chest 
coronary bypass surgeries performed in the United States, there is 
noticeable mental deterioration which is commonly attributed to cerebral 
arterial blockage from emboli released during the bypass procedure. 
Methods and devices are therefore needed for isolating the heart and 
coronary arteries from the remainder of the arterial system, arresting 
cardiac function and establishing cardiopulmonary bypass without the 
open-chest access provided by a median sternotomy or other type of 
thoracotomy. Further, the methods and devices should facilitate such 
isolation of the heart and coronary arteries without the high risk of 
embolus production associated with external aortic cross-clamps. 
One medical procedure of particular interest to the present invention is 
the treatment of heart valve disease. Co-owned, copending patent 
application Ser. No. 08/281,962, which has been incorporated by reference, 
describes a method of performing closed-chest or thoracoscopic heart valve 
replacement surgery. Isolating the heart from the systemic blood 
circulation, inducing cardioplegic arrest and establishing cardiopulmonary 
bypass are important steps in the performance of the heart valve 
replacement procedure. The devices, systems and methods of isolating and 
arresting the heart described in the present patent application will find 
particular utility in the performance of that procedure. 
Of additional interest to the invention are techniques for establishing 
cardiopulmonary bypass and for performing interventional procedures in the 
heart and great vessels which minimize trauma and risk of complications 
resulting from vascular penetrations, whether percutaneous punctures or 
surgical cutdowns. To establish cardiopulmonary bypass according to 
conventional techniques, a venous cannula is introduced into a major vein 
such as the inferior vena cava, or into the heart itself, to withdraw 
deoxygenated blood from the patient and deliver the deoxygenated blood to 
a CPB system for oxygenation. An arterial cannula is introduced into a 
major artery such as the aorta, an iliac artery, or a femoral artery, for 
delivering oxygenated blood from the CPB system to the patient's arterial 
system. 
For endovascular procedures such as angioplasty, atherectomy, 
valvuloplasty, cardiac mapping and ablation, and the like, interventional 
devices are introduced into a peripheral artery and transluminally 
positioned at the treatment site where the procedure is performed. For 
example, in angioplasty or atherectomy, a catheter is introduced into a 
femoral artery and advanced through the aorta into a coronary artery to 
treat an occluded region therein. In some circumstances, the use of CPB 
may be desirable during such procedures. If CPB is utilized during these 
procedures, the arterial and venous CPB cannulae are usually introduced 
into a femoral artery and femoral vein, respectively, by means of a 
surgical cutdown in the groin area on one side of a patient's body. The 
endovascular interventional devices may then be introduced into a femoral 
artery in the groin area on the other side of the patient's body. 
In order to minimize trauma and the risk of complications such as 
infection, it is generally desirable to minimize the number of vascular 
penetrations or "sticks" which are made in a patient during a procedure. 
Such penetrations are a significant cause of morbidity and mortality in 
cardiac procedures. The risks are greater where the penetrations are 
either surgical cutdowns or large percutaneous penetrations, as are 
usually required for introduction of venous and arterial CPB cannulae and 
for some types of endovascular interventional devices. The risks are 
particularly high when such penetrations are made on arterial vessels. 
Moreover, in some cases, one or more of a patient's femoral arteries, 
femoral veins, or other vessels for arterial and venous access may not be 
available for introduction of cannulae, due to inadequate vessel diameter, 
vessel stenosis, vascular injury, or other conditions. In such cases, 
there may not be sufficient arterial and venous access to permit the use 
of femoral arterial and venous CPB cannulae as well as other 
interventional devices, such as an angioplasty catheter, atherectomy 
catheter or other device, introduced through a femoral vein or artery 
contemporaneously as part of a single surgical procedure. Therefore, 
unless alternate arterial or venous access for one or more of these 
catheters can be found, the procedure cannot be performed using 
endovascular techniques. 
What have been needed and heretofore unavailable are methods and systems 
for satisfactorily performing various cardiovascular procedures, 
particularly procedures for heart valve placement or removal and 
replacement, which do not require a thoracotomy. Improved methods and 
devices are also needed for establishing CPB and performing interventional 
procedures that reduce the number of arterial and venous penetrations 
required for CPB cannulae and other endovascular devices. The methods and 
devices will preferably facilitate isolating the heart and coronary 
arteries from the remainder of the arterial system, arresting cardiac 
function, and establishing cardiopulmonary bypass without the open-chest 
access provided by a thoracotomy. The methods and devices should minimize 
the number of arterial and venous penetrations required in such 
closed-chest procedures, and desirably, should require no more than one 
femoral arterial penetration and one femoral venous penetration. In 
addition to procedures requiring arrest of cardiac function, the methods 
and devices should be useful for a variety of dosed-chest interventional 
procedures that require the use of cardiopulmonary bypass, even where 
cardiac function is not arrested. The present invention satisfies these 
and other needs. 
The descriptive terms downstream and upstream, when used herein in relation 
to the patient's vasculature, refer to the direction of blood flow and the 
direction opposite that of blood flow, respectively. In the arterial 
system, downstream refers to the direction further from the heart, while 
upstream refers to the direction closer to the heart. The terms proximal 
and distal, when used herein in relation to instruments used in the 
procedure, refer to directions closer to and farther away from the 
operator performing the procedure. 
SUMMARY OF THE INVENTION 
The present invention is directed to a method and system for an 
endovascular approach for preparing a patient's heart for cardiac 
procedures which does not require a grossly invasive thoracotomy. The 
invention contemplates, at least in its preferred embodiments, the 
possibility of effective ascending aortic occlusion, cardioplegia, 
venting, right heart deflation and topical cooling in association with 
extracorporeal cardiopulmonary bypass all without necessitating a median 
sternotomy or other thoracic incision. 
The endovascular system of the invention includes an elongated aortic 
partitioning catheter having proximal and distal ends and an occluding 
member on a distal portion of the catheter adapted to occlude a patient's 
ascending aorta. The catheter preferably has an inner lumen extending 
within the catheter to a port in the distal end of the catheter. The 
catheter is adapted to be inserted into the patient's arterial system 
(e.g. through the femoral or brachial arteries) and to be advanced to the 
ascending aorta where the occluding member is expanded to occlude the 
aorta at that location. In so doing the left ventricle of the heart and an 
upstream portion of the ascending aorta are separated from the rest of the 
patient's arterial system. This catheter thus constitutes an 
endovascularly inserted, internal vascular clamp, similar in function to 
the external "cross-clamp" used in open cardiac surgical procedures. The 
internal clamp is less traumatic to the clamped vessel, and provides a 
lumen or working channel through which instruments or fluids may be passed 
into or withdrawn from the area upstream of the distal end of the clamp. 
The occluding member on the elongated catheter should be dimensioned so 
that upon expansion it will be located downstream from the ostia for the 
coronary arteries and upstream from the brachiocephalic artery so as to 
avoid blocking these arteries. 
Also included with the system is a cardiopulmonary bypass system which 
withdraws blood from the patient's venous system, e.g. the femoral or 
jugular vein, removes CO.sub.2 from and adds oxygen to the withdrawn 
blood, and then returns the oxygenated blood to the patient's arterial 
system, e.g. the femoral or brachial artery. The system is also provided 
with means to deliver a fluid containing cardioplegic material (e.g. an 
aqueous solution of KCl and/or magnesium procaine and the like) through 
the coronary arteries so as to temporarily paralyze the myocardium. 
In a further aspect the present invention consists of a method for inducing 
cardioplegic arrest of a heart in situ in a patient's body, comprising the 
steps of: 
(a) maintaining systemic circulation with peripheral cardiopulmonary 
bypass; 
(b) partitioning the coronary arteries from the ascending aorta by, e.g., 
occluding the ascending aorta through a percutaneously placed arterial 
balloon catheter; 
(c) introducing a cardioplegic agent into the coronary circulation; and 
(d) venting the heart. 
The method according to the present invention may be carried out on humans 
or other mammalian animals. The method is of particular applicability in 
humans as it allows an alternative approach to open heart surgery and the 
development of closed cardioscopic surgery. The method according to the 
invention enables a percutaneous bypass system to be associated with 
cardioplegia, venting and cooling of the heart which subverts the need for 
median sternotomy. This may, in turn, reduce the complications of the 
surgery. 
In one preferred embodiment, the occluding member of the aortic 
partitioning catheter constitutes an inflatable cuff or balloon of 
sufficient size that upon being inflated it is able to completely occlude 
the ascending aorta. The length of the balloon should preferably not be so 
long as to impede the flow of blood or other solution to the coronary 
arteries or to the brachiocephalic, left carotid or left subclavian 
arteries. A balloon length of about 40 mm and diameter of about 35 mm is 
suitable in humans. The balloon may be of a cylindrical, spherical, 
ellipsoidal or other appropriate shape to fully and evenly accommodate the 
lumen of the ascending aorta. This maximizes the surface area contact with 
the aorta, and allows for even distribution of occlusive pressure. 
The balloon of the catheter is preferably inflated with a saline solution, 
or more preferably with saline solution mixed with a radiopaque contrast 
agent, to avoid the possibility of introducing into the patient an air 
embolism in the event that the balloon ruptured. The balloon should be 
inflated to a pressure sufficient to prevent regurgitation of blood into 
the aortic root and to prevent migration of the balloon into the root 
whilst not being so high as to cause damage or dilation to the aortic 
wall. An intermediate pressure of the order of 350 mmHg, for example, has 
been proven effective. 
The aortic partitioning catheter is preferably introduced under 
fluoroscopic guidance over a suitable guidewire. Transoesophageal 
echocardiography can alternatively be used for positioning the aortic 
catheter. The catheter may serve a number of separate functions and the 
number of lumina in the catheter will depend upon how many of those 
functions the catheter is to serve. The catheter can be used to introduce 
the cardioplegic agent, normally in solution, into the aortic root via one 
lumen. The luminal diameter will preferably be such that a flow of the 
order of 250-500 ml/min of cardioplegic solution can be introduced into 
the aortic root under positive pressure to perfuse adequately the heart by 
way of the coronary arteries. The same lumen can, by applying negative 
pressure to the lumen from an outside source, effectively vent the left 
heart of blood or other solutions. It may also be desirable to introduce 
medical instruments and/or a cardioscope into the heart through another 
lumen in the catheter. The lumen should be of a diameter suitable to pass 
a fiberoptic light camera of no greater than 3 mm diameter. It is however, 
preferable that the diameter and cross-sectional design of the internal 
lumina are such that the external diameter of the catheter in its entirety 
is small enough to allow its introduction into the adult femoral artery by 
either percutaneous puncture or direct cutdown. 
The oxygenated blood returning to the body from the bypass system may be 
conveyed into the aorta from another lumen in the cannula carrying the 
balloon. In this case the returning blood is preferably discarded from the 
catheter in the external iliac artery. In another embodiment of the 
invention, and in order to reduce the diameter of the catheter carrying 
the balloon, a separate arterial catheter of known type may be used to 
return blood to the patient from the bypass system. In this case a short 
catheter is positioned in the other femoral artery to provide systemic 
arterial blood from the bypass system. The control end of the catheter, 
i.e. that end that remains outside of the body, should have separate ports 
of attachment for the lumina. The catheter length should be approximately 
900 mm for use in humans. 
The cardioplegic agent may be any of the known materials previously known 
to be useful, or in the future found to be useful, as cardioplegic agents. 
The agent is preferably infused as a solution into the aortic root through 
one of the lumina of the aortic catheter. 
With the heart paralyzed, the expandable member of the aortic catheter 
expanded within the ascending aorta, and the cardiopulmonary bypass 
operating, the heart is prepared for a cardiac procedure. While a 
particularly attractive feature of the invention is that it prepares the 
heart for endovascular, thoracoscopic, and other minimally-invasive 
procedures, the invention can also be used to prepare the heart for 
conventional open-heart surgery via a thoracotomy. It should also be noted 
that, if during an endovascular cardiac procedure in accordance with the 
invention it becomes necessary to perform an open-heart procedure, the 
patient is already fully prepared for the open-heart procedure. All that 
is necessary is to perform a median sternotomy to expose the patient's 
heart for the conventional surgical procedure. 
In a further aspect, the invention provides endovascular devices and 
methods for partitioning a patient's ascending aorta between the coronary 
ostia and the brachiocephalic artery to isolate the heart and coronary 
arteries from the remainder of the arterial system, arrest cardiac 
function, and establish cardiopulmonary bypass. The invention also 
provides a system and method for arresting the heart that facilitate 
isolating the heart and coronary arteries from the remainder of the 
arterial system, arresting cardiac function, and establishing 
cardiopulmonary bypass without the need for a thoracotomy or an external 
aortic cross-clamp. 
Using the device, system and method of the invention, all blood flow 
through the ascending aorta may be blocked and cardioplegic fluid may be 
introduced through the coronary arteries to perfuse the myocardium. With 
the patient connected to cardiopulmonary bypass equipment to maintain 
circulation of oxygenated blood while the heart is stopped, surgical 
procedures may be performed on the heart, coronary blood vessels and other 
body structures using thoracoscopic and/or endovascular tools, without the 
need for a thoracotomy. Moreover, by partitioning the aorta by 
endovascular occlusion rather than by external cross-clamping, the device 
of the invention may substantially reduce the risk of embolus release 
associated with such cross-clamping. 
In a particular aspect of the invention, an endovascular device for 
partitioning the ascending aorta between the coronary ostia and the 
brachiocephalic artery comprises a flexible shaft having a distal end, a 
proximal end, and a first inner lumen therebetween with an opening at the 
distal end in communication with the first inner lumen. The shaft has a 
distal portion which is shaped so as to be positionable within the aortic 
arch such that the distal end is disposed in the ascending aorta pointing 
toward the aortic valve. Preferably, the distal portion will be shaped so 
that the distal end of the shaft is spaced apart from any interior wall of 
the aorta, and particularly, so that the distal end is aligned with the 
center of the aortic valve. Expandable means are disposed near the distal 
end of the shaft proximal to the opening at the distal end for occluding 
the ascending aorta between the coronary ostia and the brachiocephalic 
artery, thereby blocking substantially all systolic and diastolic blood 
flow. The first inner lumen of the shaft may be used to withdraw blood or 
other fluids from the ascending aorta, to introduce cardioplegic fluid 
into the coronary arteries for paralyzing the myocardium, and/or to 
introduce surgical instruments into the ascending aorta, the coronary 
arteries, or the heart for performing cardiac procedures. 
By "shaped," it is meant that the distal portion of the shaft is preset in 
a permanent, usually curved or bent shape in an unstressed condition to 
facilitate positioning the distal portion within at least a portion of the 
aortic arch, or that such a shape is imparted to the distal portion of the 
shaft by means of a shaping or deflecting element positioned over or 
within the shaft, as described in detail below. 
In one preferred embodiment, the distal portion of the shaft is preshaped 
so as to have a generally U-shaped configuration which subtends 
approximately 180.degree..+-.45.degree. of arc in an unstressed condition. 
Preferably, the U-shaped distal portion has a curvature corresponding to 
the curvature of the patient's aortic arch, usually having a radius of 
curvature in a range of 20 to 80 mm. In this way, when the preshaped 
distal portion is positioned in the aortic arch, the distal end will be 
disposed in the ascending aorta spaced apart from the interior wall 
thereof. Alternatively, the distal portion may have straight or curved 
segments with bends of relatively small radius between each segment to 
achieve a general "U" shape. The bends and/or segments of the preshaped 
distal portion may be configured to engage the interior wall of the aortic 
arch to deflect the distal end into a desired position in the ascending 
aorta. In one particular embodiment of the aortic partitioning catheter, 
the end of the catheter distal to the U-shaped curve has a straight 
segment which resides in the ascending aorta with an eccentrically shaped 
occlusion balloon mounted near the distal end of the straight segment. The 
eccentric balloon is preferably mounted on the catheter so that the larger 
side of the balloon is oriented toward the outside of the U-shaped curve, 
that is, facing toward the right side of the patient. Because the 
ascending aorta in the human is typically curved, rather than straight 
like the distal segment of the catheter, the eccentric balloon compensates 
for the mismatch of the curves and serves to center the tip of the 
catheter within the ascending aorta just above the aortic root. 
In other preferred embodiments, the distal portion is preshaped to have a 
compound curve which subtends an arc of approximately 
270.degree..+-.45.degree., preferably in the range of 
270.degree.-300.degree.. The compound curve, which may be made up of a 
combination of arc-shaped portions, angular bends and straight segments, 
serves to correctly position the distal end of the catheter within the 
ascending aorta with the catheter tip centered in the aortic lumen just 
above the aortic root and to stabilize the catheter in that position. The 
preshaped distal portion of the shaft may further have a distal segment 
which is positioned in the ascending aorta and a proximal segment which is 
positioned in the descending aorta, wherein the distal segment is skewed 
(non-coplanar) relative to the proximal segment. Such a configuration 
mirrors the orientation of the ascending aorta relative to the aortic arch 
and descending aorta, facilitating more accurate placement of the distal 
end in the ascending aorta, spaced apart from the interior wall thereof, 
and preferably, aligned with the center of the aortic valve. 
The invention preferably includes means in the shaft for straightening the 
preshaped distal portion. Usually, the straightening means comprises a 
straightening element slidably disposed in the first inner lumen having a 
stiffness greater than the stiffness of the preshaped distal portion. The 
straightening element may comprise a relatively stiff portion of a 
flexible guidewire extending through the first inner lumen, or a stylet 
having an axial passage through it for receiving a movable guidewire. 
In an exemplary embodiment, the occluding means has a collapsed profile for 
insertion into an artery such as a femoral and an expanded profile for 
occluding the ascending aorta, with the expanded profile diameter being 
about 2 to 10 times, and preferably 5 to 10 times, the collapsed profile 
diameter. In one preferred embodiment, the occluding means comprises an 
inflatable balloon made of an elastomeric material, such as polyurethane, 
silicone or latex. In other embodiments, the occlusion means comprises an 
inflatable balloon made of a nondistensible balloon material, such as 
polyethylene, polyethylene terephthalate polyester, polyester copolymers, 
polyamide or polyamide copolymers. The balloon is further configured to 
maximize contact with the aortic wall to resist displacement and prevent 
leakage around the balloon, preferably having a working surface for 
contacting the aortic wall with a length in the range of about 1 to about 
7 cm, more preferrably in the range of about 2 to 5 cm, when the balloon 
is expanded to fully occlude the vessel. 
Where a balloon is used for the occluding means, the endovascular device 
has an inflation lumen extending through the shaft from the proximal end 
to the interior of the balloon, and means connected to the proximal end of 
the inflation lumen for delivering an inflation fluid to the interior of 
the balloon. In one preferred embodiment, the inflation lumen is 
configured to allow inflation of the balloon with a liquid, such as a 
mixture of saline solution and a radiographic contrast agent, in less than 
40 seconds, preferably in approximately 20 seconds or less. In another 
preferred embodiment, the inflation fluid delivery means and the inflation 
lumen are configured to inflate the balloon with a gas such as carbon 
dioxide or helium in order to inflate the balloon in less than about 0.5 
seconds. In this way, the balloon may be fully inflated between systolic 
contractions of the heart, reducing the likelihood of balloon displacement 
caused by high pressure blood flow during systole. 
The shaft of the endovascular device of the invention may have a variety of 
configurations. The first inner lumen and inflation lumen may be coaxial, 
or a multilumen design may be employed. The shaft may further include a 
third lumen extending from the proximal end to the distal end of the 
shaft, allowing pressure distal to the occluding means to be measured 
through the third lumen. The shaft may also include means for maintaining 
the transverse dimensions of the first inner lumen, which may comprise a 
wire coil or braid embedded in at least the distal portion of the shaft to 
develop radial rigidity without loss of longitudinal flexibility. The 
shaft preferably has a soft tip at its distal end to prevent damage to the 
heart valve if the catheter comes into contact with the delicate valve 
leaflets. 
The shaft preferably has a length of at least about 80 cm, usually about 
90-125 cm, to allow transluminal positioning of the shaft from the femoral 
and iliac arteries to the ascending aorta. Alternatively, the shaft may 
have a shorter length, e.g. 20-60 cm, for introduction through the iliac 
artery, through the brachial artery, through the carotid artery, or 
through a penetration in the aorta itself. 
Because of its proximity to the left ventricle, the occluding means of the 
device is subject to significant forces from the outflow of blood during 
systole. Such forces could threaten to displace the occluding means either 
downstream where it might occlude the ostium of the brachiocephalic or 
other artery, or upstream (in a recoil effect) where the occluding means 
might damage the aortic valve or occlude the coronary ostia. 
Advantageously, the endovascular device of the invention is configured to 
maintain the position of the occluding means in the ascending aorta 
against the force of systolic outflow as the occluding means is expanded 
and retracted, as well as during the period in which the occluding means 
fully occludes the aorta but the heart remains beating. 
In addition, the shaped distal portion of the device maintains the distal 
end in a radial position spaced apart from the interior wall of the 
ascending aorta such that the distal opening is unobstructed and generally 
aligned with the center of the aortic valve. This facilitates aspiration 
of blood, other fluids, or debris, infusion of fluids, or introduction of 
instruments through the distal opening in the endovascular device without 
interference with the aortic wall or aortic valve tissue. 
In a further preferred embodiment, the invention provides a system for 
selectively arresting the heart which includes an endovascular aortic 
partitioning device as just described, along with means for paralyzing the 
patient's myocardium. Usually, the means for paralyzing the myocardium 
comprises means connected to the proximal end of the shaft for delivering 
cardioplegic fluid through the first inner lumen and out of the opening at 
the distal end of the device upstream of the occluding means. In this way, 
the occluding means may be expanded to stop blood flow through the 
ascending aorta, and cardioplegic fluid may be delivered through the first 
inner lumen to the aortic root and the coronary arteries to perfuse the 
myocardial tissue, thereby arresting the heart. The system may further 
include a cardiopulmonary bypass system having means for withdrawing blood 
from a venous location upstream of the heart, means for oxygenating the 
withdrawn blood, and means for directing the oxygenated blood to an 
arterial location downstream of the occluding means. 
According to the method of the invention, the distal end of the shaft of 
the endovascular partitioning device is introduced into a blood vessel 
downstream of the patient's aortic arch. The shaft is transluminally 
positioned so that the distal end is in the ascending aorta and the 
expandable occluding member attached to the shaft near the distal end is 
disposed between the coronary ostia and brachiocephalic artery. The 
occluding member is then expanded within the ascending aorta to completely 
block blood flow therethrough for a plurality of cardiac cycles. 
In those embodiments in which the shaft of the partitioning device has a 
preshaped distal portion, the method will usually include the step of 
straightening the preshaped distal portion to facilitate introduction into 
the blood vessel, usually by positioning a stylet or guidewire in an inner 
lumen in the shaft. The stylet may be withdrawn from the shaft as the 
distal portion is advanced into the ascending aorta to allow the distal 
portion to resume its preshaped configuration. In a particular embodiment, 
the method may further include, before the step of introducing the shaft 
into the blood vessel, the steps of determining a size of the patient's 
aortic arch, and selecting a shaft having a shaped distal portion 
corresponding to the dimensions and geometry of the aortic arch. 
Preferably, the shaft of the partitioning device is introduced through a 
femoral or iliac artery, brachial artery, carotid artery or other artery 
which is percutaneously accessible without a thoracotomy. In this way, the 
device may be introduced and advanced into position with the patient's 
sternum and rib cage intact. 
When the occluding member is an inflatable balloon, the method further 
includes the step of delivering an inflation fluid to the balloon through 
an inner lumen in the shaft of the device. The inflation fluid may be 
either a liquid or a gas. In one embodiment, the inflation medium is an 
aqueous liquid containing a radiopaque contrast agent which is delivered 
at a rate to inflate the balloon in 40 seconds or less, preferably 20 
seconds or less. In another embodiment, the inflation medium is a gas 
which is delivered at a rate to completely occlude the aorta between 
systolic contractions of the heart, usually in less than about 0.5 second. 
The method may further include paralyzing the patient's myocardium while 
the occluding means is expanded in the ascending aorta. Usually, this will 
be accomplished by infusing cardioplegic fluid through an inner lumen in 
the shaft of the partitioning device into the ascending aorta upstream of 
the occluding member. The cardioplegic fluid perfuses the myocardium 
through the coronary arteries to arrest heart contractions. In this 
embodiment, the method further includes the steps of withdrawing blood 
from a venous location upstream of the patient's heart, oxygenating the 
withdrawn blood, and directing the oxygenated blood to an arterial 
location downstream of the occluding member, thereby maintaining 
circulation of oxygenated blood throughout the remainder of the patient's 
arterial system. 
Thus, using the system and method of the invention, a patient's heart can 
be arrested and the patient placed on cardiopulmonary bypass without a 
thoracotomy, thereby reducing mortality and morbidity, decreasing patient 
suffering, reducing hospitalization and recovery time, and lowering 
medical costs relative to previous open-chest procedures. The endovascular 
partitioning device of the invention permits blood flow through the 
ascending aorta to be completely blocked between the coronary ostia and 
the brachiocephalic artery in order to isolate the heart and coronary 
arteries from the remainder of the arterial system. This has significant 
advantages over the aortic cross-clamps used in current cardiac 
procedures, not only obviating the need for a thoracotomy, but providing 
the ability to stop blood flow through the aorta even when calcification 
or other complications would make the use of an external cross-clamp 
undesirable. 
With the endovascular partitioning device in place, the heart arrested and 
cardiopulmonary bypass established, the patient is prepared for a variety 
of surgical and diagnostic procedures, including repair or replacement of 
aortic, mitral and other heart valves, repair of septal defects, pulmonary 
thrombectomy, coronary artery bypass grafting, angioplasty, atherectomy, 
electrophysiological mapping and ablation, treatment of aneurysms, 
myocardial drilling, as well as neurovascular and neurosurgical 
procedures. While such procedures may be performed through a thoracotomy 
in the conventional manner, the invention provides the capability for 
performing procedures such as heart valve replacement or coronary artery 
bypass grafting using minimally-invasive techniques, either by means of 
surgical tools introduced endovascularly through the partitioning device 
itself, or by means of thoracoscopic tools introduced through small 
incisions in the chest wall. 
In an alternate method of the present invention, the cardioplegic fluids 
may be delivered to the myocardium by retrograde perfusion of the coronary 
circulation. Using this technique, a physician will percutaneously 
introduce a catheter through a major vein, e.g. the right internal jugular 
vein, and advance the catheter in the venous system until the distal end 
of the catheter extends into the coronary sinus through the discharge 
opening thereof in the right atrium. Preferably, the catheter has an 
inflatable balloon on the distal end thereof, such as those shown in U.S. 
Pat. No. 4,689,041, U.S. Pat. No. 4,943,277, and U.S. Pat. No. 5,021,045, 
which are incorporated herein by reference. When inflated, the balloon 
blocks the discharge opening of the coronary sinus to preclude loss of 
cardioplegic fluid therefrom. With the discharge opening of the coronary 
sinus blocked off, aqueous liquid or other fluid containing cardioplegic 
material is delivered through the catheter into the coronary sinus at 
sufficient pressure so that it passes into the myocardium via the 
capillary bed between the venous and arterial systems therein so as to 
paralyze the entire myocardium. Typically, cardioplegic solution pressure 
within the coronary sinus should be less than 50 mm Hg to avoid tissue 
damage. After passing through the myocardium, the cardioplegic liquid will 
pass through the coronary arteries in a retrograde fashion to be 
discharged through the coronary ostia into the upstream portion of the 
ascending aorta. The cardioplegic fluid which discharges from the coronary 
ostia will initially be very opaque due to blood being flushed out of the 
coronary circulation, but eventually the fluid will become clear and may 
be conveniently used to form and maintain the body of clear fluid at the 
surgical site to facilitate the imaging thereof during the procedure. In 
some instances, cardioplegic liquid may instead be delivered through the 
coronary arteries in an antegrade fashion, either via catheters placed 
through the coronary ostia into the coronary arteries or by delivery via 
the aortic catheter directly into the aortic root. 
The present invention further provides endovascular devices and methods for 
establishing cardiopulmonary bypass and performing interventional 
procedures within the heart and great vessels with a minimum of arterial 
and venous penetrations. Using the devices and methods of the invention, 
all blood flow through the ascending aorta may be blocked, cardioplegic 
fluid may be introduced through the coronary arteries to perfuse the 
myocardium, and oxygenated blood from a CPB system may be infused into the 
arterial system downstream from the point of aortic occlusion, all through 
a single femoral arterial penetration. Moreover, blood may be vented from 
the heart to prevent distension of the myocardium, and deoxygenated blood 
withdrawn from a venous location for oxygenation by the CPB system, all 
through a single femoral or jugular venous penetration. 
In an additional aspect of the invention, a cardiopulmonary bypass cannula 
is provided which is adapted to allow endovascular introduction of the 
endoaortic partitioning catheter through a lumen of the cannula so as to 
reduce the number of cutdowns or percutaneous arterial or venous punctures 
necessary for establishing cardiopulmonary bypass. The shaft of the 
endoaortic partitioning catheter is slidably disposed in the blood flow 
lumen of the bypass cannula, and may be removable from the bypass cannula, 
and/or limited in its movement relative to the bypass cannula. The bypass 
cannula may further be provided with a plurality of ports along a distal 
portion of its length in fluid communication with the blood flow lumen to 
enhance the flow of blood into or out of the blood flow lumen. In the 
arterial embodiment, the blood flow lumen is preferably configured to 
facilitate a fluid flow of at least about 4 liters/minute at a pressure of 
less than about 250 mmHg. 
The bypass cannula may further have an adapter assembly mounted to its 
proximal end. The adapter assembly has first and second access ports in 
communication with the blood flow lumen, the first access port being 
configured to receive the catheter shaft, and the second access port being 
configured for connection to the oxygenated blood delivery means (in the 
arterial embodiment) or a means for receiving and oxygenating deoxygenated 
blood (in the venous embodiment). Usually, a hemostasis valve or other 
sealing means is mounted in the first access port to prevent leakage of 
blood therefrom, both when the catheter shaft is inserted through the 
first access port as well as when the catheter shaft is removed from the 
first access port. In the arterial embodiment, the bypass cannula has a 
length between about 10 cm and 60 cm, and preferably about 15 cm to 30 cm, 
such that the outflow port at the distal end of the bypass cannula is 
disposed a substantial distance downstream of the occluding member on the 
catheter shaft. If it is used on the venous side, the bypass cannula is 
preferably about 50 cm to 90 cm in length so as to extend from a femoral 
vein to a point in the inferior vena cava near the heart, to a point 
within the right atrium of the heart, or to a point in the superior vena 
cava near the heart. Alternatively, the venous bypass cannula may be 
configured for introduction into the internal jugular vein and positioning 
therefrom into the superior vena cava, the right atrium, or the inferior 
vena cava. 
According to the method of the invention, a distal end of a bypass cannula 
is positioned in a blood vessel of a patient, and a proximal end of the 
bypass cannula is connected to a CPB system to permit blood flow through a 
blood flow lumen in the bypass cannula between the blood vessel and the 
CPB system. An interventional device is then introduced through the blood 
flow lumen of the bypass cannula into the blood vessel and advanced into 
the heart or into a great vessel near the heart to perform an 
interventional procedure therein. 
In a particular embodiment, the bypass cannula is introduced into an artery 
downstream of the patient's ascending aorta, and a distal end of a 
catheter shaft is introduced into the artery through the blood flow lumen 
in the bypass cannula. The catheter shaft is transluminally positioned so 
that an expandable occluding member attached to the catheter shaft near 
the distal end is disposed between the patient's coronary ostia and the 
patient's brachiocephalic artery. Oxygenated blood is infused into the 
artery downstream of the occluding member through a lumen in the bypass 
cannula. The occluding member is expanded within the ascending aorta to 
completely block blood flow therethrough for a plurality of cardiac 
cycles. The patient's myocardium is then paralyzed. 
In most embodiments, the bypass cannula will be connected to a CPB system 
which withdraws blood from a venous location in the patient, oxygenates 
the blood, and delivers the oxygenated blood to the blood flow lumen in 
the bypass cannula on the arterial side. The deoxygenated blood may be 
withdrawn through a blood flow lumen in a venous cannula positioned in a 
vein such as a femoral vein or internal jugular vein. Also, a cardiac 
venting catheter may be positioned in the heart, usually in the pulmonary 
artery, to withdraw blood therefrom and deliver it to the CPB system. In 
an exemplary embodiment, the cardiac venting catheter is introduced 
through the blood flow lumen in the venous cannula. Preferably, the venous 
and arterial bypass cannulae are introduced into a femoral vein and 
femoral artery, respectively, in the groin area on the same side of the 
patient. In this way, both the venous and arterial bypass cannulae, as 
well as the devices introduced therethrough, may be introduced through a 
single surgical cutdown or percutaneous punctures on a single side of the 
patient. 
Thus, using the system and method of the invention, a patient's heart can 
be arrested and the patient placed on cardiopulmonary bypass without a 
conventional gross thoracotomy, thereby reducing mortality and morbidity, 
decreasing patient suffering, reducing hospitalization and recovery time, 
and lowering medical costs relative to previous open-chest procedures. The 
endovascular partitioning device of the invention permits blood flow 
through the ascending aorta to be completely blocked between the coronary 
ostia and the brachiocephalic artery in order to isolate the heart and 
coronary arteries from the remainder of the arterial system. This has 
significant advantages over the aortic cross-clamps used in current 
cardiac procedures, not only obviating the need for a gross thoracotomy, 
but providing the ability to stop blood flow through the aorta even when 
calcification or other complications would make the use of an external 
cross-clamp undesirable. Moreover, the device and method of the invention 
accomplish this with a minimum of arterial penetrations, thereby 
minimizing trauma and the risk of complications such as infection. 
The system and method of the invention may further be useful to provide 
cardiopulmonary bypass during endovascular interventional procedures in 
which cardiac function may or may not be arrested. Such procedures may 
include angioplasty, atherectomy, heart valve repair and replacement, 
septal defect repair, treatment of aneurysms, myocardial mapping and 
ablation, myocardial drilling, and a variety of other procedures wherein 
endovascular interventional devices are introduced through the bypass 
cannula of the invention and advanced into the heart or great vessels. In 
this way, the invention facilitates cardiopulmonary bypass during such 
procedures without requiring additional arterial or venous penetrations. 
The occluding aortic catheter with an expandable occluding member on the 
distal end, coupled with cardiopulmonary bypass, cardioplegia, and 
decompression of the left atrium, provides for a unique endovascular 
approach to a wide variety of cardiac procedures, an approach which does 
not require invasive thoracic or abdominal surgery. In addition the system 
may be used in minimally invasive cardiac procedures under thoracoscopic 
guidance, working through incisions in the patient's chest from outside 
the patient's body. In these instances the occluding catheter need not 
have an inner lumen for delivery of fluids and the like. The catheter and 
method according to the present invention can be used to induce 
cardioplegic arrest and may be used in a number of surgical procedures. 
Moreover, as mentioned, the system may even be employed in conventional 
open-heart procedures. These and other advantages of the invention will 
become more apparent from the following detailed description of the 
invention when taken in conjunction with the accompanying exemplary 
drawings.

DETAILED DESCRIPTION OF THE INVENTION 
The invention provides a cardiac access system including an endovascular 
device for partitioning the ascending aorta, as well as a system for 
selectively arresting the heart, which are useful in performing a variety 
of cardiovascular, pulmonary, neurosurgical, and other procedures. The 
procedures with which the invention will find use include repair or 
replacement of aortic, mitral, and other heart valves, repair of septal 
defects, pulmonary thrombectomy, electrophysiological mapping and 
ablation, coronary artery bypass grafting, angioplasty, atherectomy, 
treatment of aneurysms, myocardial drilling and revascularization, as well 
as neurovascular and neurosurgical procedures. The invention is especially 
useful in conjunction with minimally-invasive cardiac procedures, in that 
it allows the heart to be arrested and the patient to be placed on 
cardiopulmonary bypass using only endovascular devices, obviating the need 
for a thoracotomy or other large incision. Moreover, even in conventional 
open-chest procedures, the endovascular aortic partitioning device of the 
invention will frequently find use where an external cross-clamp would 
raise substantial risks of embolus release due to calcification or other 
aortic conditions. 
Reference is made to FIG. 1 which schematically illustrates the overall 
cardiac accessing system of the invention and the individual components 
thereof. The accessing system includes an elongated aortic occlusion or 
endoaortic partitioning catheter 10 which has an expandable member 11 on a 
distal portion of the catheter which, when inflated as shown, occludes the 
ascending aorta 12 to separate or partition the left ventricle 13 and 
upstream portion of the ascending aorta from the rest of the patient's 
arterial system and securely positions the distal end of the catheter 
within the ascending aorta. A cardiopulmonary bypass system 18 removes 
venous blood from the femoral vein 16 through the blood withdrawal 
catheter 17 as shown, removes CO.sub.2 from the blood, oxygenates the 
blood, and then returns the oxygenated blood to the patient's femoral 
artery 15 through the return catheter 19 at sufficient pressure so as to 
flow throughout the patient's arterial system except for the portion 
blocked by the expanded occluding member 11 on the aortic occluding 
catheter 10. The aortic occluding catheter 10 has an infusion lumen 40 for 
antegrade delivery of a fluid containing cardioplegic agents directly into 
the aortic root 12 and subsequently into the coronary arteries 52, 53 
(shown in FIG. 2) to paralyze the patient's myocardium. Optionally, a 
retrograde cardioplegia balloon catheter 20 may be disposed within the 
patient's venous system with the distal end of the catheter extending into 
the coronary sinus 21 (shown in FIG. 4) to deliver a fluid containing 
cardioplegic agents to the myocardium in a retrograde manner through the 
patient's coronary venous system to paralyze the entire myocardium. 
The elongated occluding catheter 10 extends through the descending aorta to 
the left femoral artery 23 and out of the patient through a cut down 24. 
The proximal extremity 25 of the catheter 10 which extends out of the 
patient is provided with a multi-arm adapter 26 with one arm 27 adapted to 
receive an inflation device 28. The adapter 26 is also provided with a 
second arm 30 with main access port 31 through which passes instruments, a 
valve prosthesis, an angioscope, or to direct blood, irrigation fluid, 
cardioplegic agents and the like to or from the system. A third arm 32 is 
provided for monitoring aortic root infusion pressure at the distal end of 
the catheter and/or for directing blood, irrigation fluid, and the like to 
or from the system. In the system configuration of FIG. 1, the third arm 
32 of the multi-arm adapter 26 is connected to a cardioplumonary bypass 
line 33 to vent the patient's heart, particularly the left ventricle, and 
to recover the blood removed and return it to the patient via the 
cardioplumonary bypass system. A suitable valve 34 is provided to open and 
close the bypass line 33 and direct the fluid passing through the bypass 
line to a discharge line 35 or a line 36 to a blood filter and recovery 
unit 37. A return line may be provided to return any filtered blood to the 
cardiopulmonary bypass system 18 or other blood conservation system. 
The details of the aortic occlusion catheter 10 and the disposition of the 
distal extremity thereof within the aorta are best illustrated in FIGS. 2 
and 3. As indicated, the catheter 10 includes an elongated catheter shaft 
39 which has a first inner lumen 40 for infusion of a cardioplegic agent 
in fluid communication with the main access port 31 in the second arm of 
the adapter 26. Additionally, the infusion lumen 40 may be adapted to 
facilitate the passage of instruments, a valve prosthesis, an angioscope, 
irrigation fluid, and the like therethrough and out the distal port 41 in 
the distal end thereof. A supporting coil 42 may be provided in the distal 
portion of the first inner lumen 40 to prevent the catheter shaft 39 from 
kinking when it straightened for initial introduction into the arterial 
system or when it is advanced through the aortic arch. The shaft 39 is 
also provided with a second inner lumen 43 which is in fluid communication 
with the interior of the occluding balloon 11. 
In one embodiment of the system, a retrograde cardioplegia balloon catheter 
20, which is shown in more detail in FIG. 4, is introduced into the 
patient's venous system through the right internal jugular vein 44 and is 
advanced through the right atrium 45 and into the coronary sinus 21 
through the coronary sinus discharge opening 46 in the right atrium. The 
retrograde catheter 20 is provided with a balloon 47 on a distal portion 
of the catheter 20 which is adapted to occlude the coronary sinus 21 when 
inflated. A liquid containing a cardioplegic agent, e.g. an aqueous KCl 
solution, is introduced into the proximal end 48 of the catheter 20, which 
extends outside of the patient, under sufficient pressure so that the 
fluid containing the cardioplegic agent can be forced to pass through the 
coronary sinus 21, through the capillary beds (not shown) in the patient's 
myocardium, through the coronary arteries 50 and 51 and ostia 52 and 53 
associated with the respective coronary arteries into the blocked off 
portion of the ascending aorta 12 as shown. 
A pulmonary venting catheter 54 is also shown in FIG. 4 disposed within the 
right internal jugular vein 44 and extending through the right atrium 45 
and 1 0 right ventricle 55 into the pulmonary trunk 56. The catheter 54 
passes through tricuspid valve 57 and pulmonary valve 58. An inflatable 
occluding balloon 60 may be provided as shown on a distal portion of the 
pulmonary venting catheter 54 which is inflated to occlude the pulmonary 
trunk 56 as shown. The pulmonary venting catheter 54 has a first inner 
lumen 61 which extends from the distal end of the catheter to the proximal 
end of the catheter which vents fluid from the pulmonary trunk 56 to 
outside the patient's body either for discharge or for passage to the 
blood recovery unit and thereby decompresses the left atrium 14 through 
the pulmonary capillary beds (not shown). The catheter 54 has a second 
inner lumen 62 which is adapted to direct inflation fluid to the interior 
of the inflatable balloon 60. 
To set up the cardiac access system, the patient is initially placed under 
light general anesthesia. The withdrawal catheter 17 and the return 
catheter 19 of the cardiopulmonary bypass system 18 are percutaneously 
introduced into the right femoral vein 16 and the right femoral artery 15, 
respectively. An incision 24 is also made in the left groin to expose the 
left femoral artery 23 and the aortic occluding catheter 10 is inserted 
into the left femoral artery through an incision therein and advanced 
upstream until the balloon 11 on the distal end of the occluding catheter 
10 is properly positioned in the ascending aorta 12. Note that bypass 
could similarly be established in the left groin and the aortic occlusion 
catheter put into the right femoral artery. The retrograde perfusion 
catheter 20 is percutaneously inserted by a suitable means such as the 
Seldinger technique into the right internal Jugular vein 44 or the 
subclavian vein and advanced into the right atrium 45 and guided through 
the discharge opening 46 into the coronary sinus. 
The pulmonary venting catheter 54 is advanced through the right internal 
jugular vein 44 or the subclavian vein (whichever is available after 
introduction of retrograde perfusion catheter 20) into the right atrium 
45, right ventride 55, and into the pulmonary trunk 56. The occluding 
balloon 60 may be inflated if necessary by inflation with fluid passing 
through the lumen 62 to block the pulmonary trunk 56 and vent blood 
therein through the lumen 61 where it is discharged through the proximal 
end of the catheter which extends outside of the patient. Alternatively, 
the occluding ballon 60 may be partially inflated with air or CO.sub.2 
during introduction for flow-assisted placement. The venting of the 
pulmonary trunk 56 results in the decompressing of the left atrium 14 and, 
in turn, the left ventricle. In the alternative, the venting catheter 54 
may be provided with means on the exterior thereof, such as expanded coils 
as described in U.S. Pat. No. 4,889,137 (Kolobow), which hold open the 
tricuspid and pulmonary valves and perform the same function of 
decompressing the left atrium. See also the article written by F. Rossi 
et. al. in the Journal of Thoracic Cardiovascular Surgery, 
1900;100:914-921, entitled "Long-Term Cardiopulmonary Bypass By Peripheral 
Cannulation In A Model Of Total Heart Failure", which is incorporated 
herein in its entirety by reference. 
The operation of the cardiopulmonary bypass unit 18 is initiated to 
withdraw blood from the femoral vein 16 through catheter 17, remove 
CO.sub.2 from and add oxygen to the withdrawn blood and then pump the 
oxygenated blood through the return catheter 19 to the right femoral 
artery 15. The balloon 11 may then be inflated to occlude the ascending 
aorta 12, causing the blood pumped out of the left ventricle (until the 
heart stops beating due to the cardioplegic fluid as discussed 
hereinafter) to flow through the discharge port 41 into the first inner 
lumen 40 of the occluding catheter. The blood flows through the inner 
lumen 40 and out the third arm 32 of the adapter 26 into the bypass line 
33 and then into the blood filter and blood recovery unit 37 through the 
valve 34 and line 36. For blood and irrigation fluids containing debris 
and the like, the position of the valve 34 may be changed to direct the 
fluid through the discharge line 35. 
In a first embodiment of the method, a liquid containing a cardioplegic 
agent such as KCl is directed through the infusion lumen 40 of the 
catheter 10 into the aortic root 12 and subsequently into the coronary 
arteries 52, 53 to paralyze the patient's myocardium. Alternatively, if a 
retroperfusion catheter 20 is provided for delivery of the cardioplegic 
agent, the balloon 47 on the distal extremity of the catheter 20 is 
inflated to occlude the coronary sinus 21 to prevent fluid loss through 
the discharge opening 46 into the right atrium 45. A liquid containing a 
cardioplegic agent such as KCl is directed through the catheter 20 into 
the coronary sinus 21 and the pressure of the cardioplegic fluid within 
the coronary sinus 21 is maintained sufficiently high, (e.g. 40 mm Hg) so 
that the cardioplegic fluid will pass through the coronary veins, crossing 
the capillary beds to the coronary arteries 50 and 51 and out the ostia 52 
and 53. The cardioplegic fluid pressure within the coronary sinus 21 
should be maintained below 75 mm Hg to avoid pressure damage to the 
coronary sinus 21. Once the cardioplegic fluid passes through the 
capillary beds in the myocardium, the heart very quickly stops beating. At 
that point the myocardium is paralyzed and has very little demand for 
oxygen and can be maintained in this state for long periods of time with 
minimal damage. 
With the cardiopulmonary bypass system in operation, the heart completely 
paralyzed and not pumping, the left atrium and ventricle decompressed and 
the ascending aorta blocked by the inflated balloon 11 on the occluding 
catheter 10, the heart is appropriately prepared for a cardiac procedure. 
Inflation of the inflatable member 11 on the distal end of the delivery 
catheter 10 fixes the distal end of the occluding catheter 10 within the 
ascending aorta 12 and isolates the left ventride 13 and the upstream 
portion of the ascending aorta from the rest of the arterial system 
downstream from the inflatable member. The passage of any debris or 
emboli, solid or gaseous, generated during a cardiovascular procedure to 
regions downstream from the site would be precluded by the inflated 
balloon 11. Fluid containing debris or emboli can be removed from the 
region between the aortic valve and the occluding balloon 11 through the 
inner lumen 40 of catheter 10. A dear, compatible fluid, e.g. an aqueous 
based fluid such as saline delivered through the inner lumen 40 or the 
cardioplegic fluid discharging from the coronary ostia 52 and 53, may be 
maintained in the region wherein the cardiovascular procedure is to be 
performed to facilitate use of an angioscope or other imaging means that 
allows for direct observation of the cardiac procedure. Preferably, the 
fluid pressure in the left ventricle 13 is maintained sufficiently higher 
than that in the left atrium to prevent blood from the left atrium from 
seeping into the left ventricle and interfering with the observation of 
the procedure. 
FIG. 5A shows a longitudinal cross section of a first preferred embodiment 
of the endoaortic partitioning catheter 100 of the present invention. The 
endoaortic partitioning catheter 100 of FIG. 5A is made with a coaxial 
construction, which indicates that the catheter 100 is constructed of a 
first, inner tube 102 within a second, outer tube 104. The inner tube 102 
and the outer tube 104 of the catheter 100 combine to form an elongated 
shaft 106 that runs from a proximal hub 108 to the distal end of the 
catheter 100 having an aortic occlusion balloon 110 mounted thereon. The 
length of the shaft 106 is such that the catheter 100 can be introduced 
into the patient's aorta by way of an arterial cutdown or the Seldinger 
technique into a peripheral artery, such as the femoral or brachial 
artery, and advanced into the ascending aorta. For introduction by way of 
a femoral artery or iliac artery the length of the shaft 106 is preferably 
80 to 125 cm. For introduction by way of a brachial artery, the carotid 
artery or through a penetration directly into the aorta, the length of the 
shaft 106 is preferably 20 to 80 cm. 
In the embodiment of FIG. 5A, the inner tube 102 of the catheter 100 is a 
two lumen tube, having a crescent-shaped cardioplegia infusion lumen 112 
which wraps around a circular distal pressure lumen 114, as shown in cross 
section in FIGS. 5B and 5C. The cardioplegia infusion lumen 112 and the 
distal pressure lumen 114 are open at the distal end of the catheter 100. 
The cardioplegia infusion lumen 112 preferably has a cross sectional area 
sufficient for delivering a mixture of warm or cooled, oxygenated blood 
and cardioplegia solution at a rate of from about 200 ml/min to 400 ml/min 
with an infusion pressure not to exceed 300 mmHg. In one presently 
preferred embodiment, the cross sectional area of the cardioplegia 
infusion lumen 112 is approximately 5.74 mm.sup.2 (0.00889 in.sup.2) for a 
catheter with a length of about 120-130 cm. The cross sectional area of 
the cardioplegia infusion lumen 112 necessary to deliver the desired flow 
rate will vary somewhat depending on the length of the catheter shaft 106 
and the ratio of blood to cardioplegic solution in the mixture. The distal 
pressure lumen 114 preferably has a cross sectional area sufficient to 
transmit the pressure within the aortic root along the length of the 
catheter shaft 106 without excessive damping of the pressure wave. In a 
preferred embodiment having a shaft length of about 120-130 cm, a distal 
pressure lumen 114 having an internal diameter of 0.61 mm, and therefore a 
cross sectional area of 0.29 mm.sup.2 (0.00045 in.sup.2), provides the 
desired pressure signal transmission. 
The outer tube 104 of the catheter 100 fits coaxially around the inner tube 
102 with an annular space between the two tubes providing a balloon 
inflation lumen 116, as shown in cross section in FIG. 5B. The external 
diameter of the catheter 100 can be made within the range of 8-23 French 
(Charriere scale), preferably in the range of 8-12 French. In one 
preferred embodiment of the catheter 100, the outer tube 104 has an 
external diameter of 3.4-3.5 mm or approximately 10.5 French (Charriere 
scale). In a second preferred embodiment of the catheter 100, the outer 
tube 104 has an external diameter of 3.2-3.3 mm or approximately 10 French 
(Charriere scale). An aortic occlusion balloon 110 is mounted on the 
distal end of the catheter 100. The aortic occlusion balloon 110 has a 
proximal balloon neck 118 which is sealingly attached to the outer tube 
104 and a distal balloon neck 120 which is sealingly attached to the inner 
tube 102 of the catheter 100 so that the balloon inflation lumen 116 
communicates with the interior of the balloon 110. Preferably, the balloon 
inflation lumen 116 has a cross sectional area of approximately 0.5-1.0 
mm.sup.2 (0.00077-0.00155 in.sup.2) to allow rapid inflation and deflation 
of the aortic occlusion balloon 110. In a particular presently preferred 
embodiment with the described configuration, the balloon inflation lumen 
116 has a cross sectional area of approximately 0.626 mm.sup.2 (0.00097 
in.sup.2) which allows the occlusion balloon 110 be inflated to a 
recommended maximum volume of 40 cc with saline solution or saline 
solution mixed with a radiopaque contrast agent at an inflation pressure 
of 35 psi in 40 seconds or less, preferably in 20 seconds or less. Whether 
inflating by hand or using a mechanical inflation device, the inflation of 
the balloon is preferably volume-limited so that, although the transient, 
peak inflation pressure reaches approximately 35 psi, the inlation 
pressure decreases to about 10-12 psi to maintain balloon inflation when 
the balloon reaches its desired inflation volume. The balloon inflation 
lumen 116 also allows the occlusion balloon 110 be deflated in 60 seconds 
or less, preferably in 40 seconds or less. The occlusion balloon 110 can 
be inflated and deflated by hand using an ordinary syringe or it can be 
inflated and deflated using an inflation device which provides a 
mechanical advantage or that is powered by compressed air or an electric 
motor. 
FIG. 5D is a detail drawing showing the construction of section 5D--5D of 
the catheter 100 of FIG. 5A. The proximal balloon neck 118 is bonded to 
the distal end of the outer tube 104 in a lap joint. The bond between the 
proximal balloon neck 118 and the outer tube 104 and the bond between the 
distal balloon neck 120 and the inner tube 102 can be formed by adhesive 
bonding, by solvent bonding or by heat bonding depending on the materials 
chosen for each component. 
Alternatively, the outer tube 104 can be formed from a single continuous 
extrusion with the material of the aortic occlusion balloon 110. 
The proximal hub 108 of the catheter 100 has a luer fitting balloon 
inflation port 122 that is sealingly connected to the balloon inflation 
lumen 116, a luer fitting pressure monitoring port 124 that is sealingly 
connected to the distal pressure lumen 114, and an infusion port 126 that 
is sealingly connected to the cardioplegia infusion lumen 112. The 
proximal hub 108 may be joined to the proximal ends of the inner tube 102 
and the outer tube 104 by adhesive bonding, by insert molding or by other 
known processes. 
In the embodiment of FIG. 5A, the aortic occlusion balloon 110 is shown as 
having a generally spherical geometry in the unexpanded state 110, as well 
as a generally spherical geometry in the expanded or inflated state 110'. 
Other possible geometries for the balloon in the unexpanded state 110 
include cylindrical, oval or football-shaped, eccentric or other shaped 
balloons. Some of these variations are further described below. In this 
preferred embodiment the balloon 110 is made of an elastomeric material 
that expands elastically from the uninflated to the inflated state. 
Preferred materials for the balloon 110 include latex, silicone, and 
polyurethane, chosen for their elasticity, strength and biocompatibility 
for short term contact with the blood and body tissues. 
FIG. 6A shows a lateral side view of a second preferred embodiment of the 
endoaortic partitioning catheter 200. In this embodiment the inner tube 
202 has been made with a D-shaped cardioplegia infusion lumen 212 and a 
D-shaped distal pressure lumen 214. The choice of D-shaped lumens in the 
inner tube 202, makes it possible to maximize the diametrical clearance 
within the cardioplegia infusion lumen 212 for a given cross sectional 
area, as compared to the crescent-shaped cardioplegia infusion lumen 112 
of FIG. 5C. This variation of the catheter 200 may be preferable when 
catheters or other instruments are to be introduced to the heart and its 
associated blood vessels through the cardioplegia infusion lumen 212. 
As shown in FIG. 6A, the occlusion balloon 210 of this embodiment has an 
ellipsoidal or football-shaped deflated profile which is imparted by the 
balloon molding process. The wall thickness of the molded balloon 210 in 
its deflated state is typically about 0.090-0.130 mm. Typically, the 
deflated balloon 210 has a diameter of approximately 12 mm before it is 
folded, although deflated balloon diameters of 3 to 20 mm are possible. 
The inflated balloon 210' assumes a roughly spherical shape with a maximum 
diameter of approximately 40 mm when inflated. The football shape of the 
molded balloon has been shown to be advantageous in that the deflated 
balloon 210 has a deflated profile which is less bulky and smoother than 
for other balloon geometries tested. This allows the deflated balloon 210 
to be folded and more easily inserted through a percutaneous puncture into 
the femoral artery or through an introducer sheath or a dual function 
arterial cannula and introducer sheath. In this embodiment as well, the 
balloon 210 is preferably made of an elastomeric material such as latex, 
silicone, or polyurethane. In one particular embodiment, the 
football-shaped balloon has an internal geometry determined by a positive 
dip molding mandrel with a radius of curvature in the central portion of 
the balloon of approximately 1.0 inch with a maximum diameter in the 
center of the balloon of about 0.5 inch. The curvature of the central 
portion of the balloon has a smoothly radiused transition, for example 
with a radius of about 0.25 inch, to the proximal and distal balloon 
sleeves, which are sized to fit snugly onto the exterior of the chosen 
diameter catheter shaft. 
FIG. 7A shows a longitudinal cross section of a third preferred embodiment 
of the endoaortic partitioning catheter 300. The catheter 300 of this 
embodiment has a coaxial construction having a single lumen inner tube 302 
surrounded by a single lumen outer tube 304. The single lumen inner tube 
302 has a circular cardioplegia infusion lumen 312 that is connected on 
its proximal end to the infusion port 326 of the proximal hub 308 of the 
catheter 300. The cardioplegia infusion lumen 312 is open at the distal 
end of the catheter 300. The single lumen outer tube 304 of the catheter 
300 fits coaxially around the inner tube 302 with an annular space between 
the two tubes providing a balloon inflation lumen 316. The balloon 
inflation lumen 316 is connected on its proximal end to the balloon 
inflation port 322 of the proximal hub 308. 
In this embodiment, the aortic root pressure monitoring function is 
fulfilled by a distal pressure transducer 330 mounted at the distal tip 
332 of the catheter 300. The distal pressure transducer 330 electronically 
monitors the aortic root pressure and transmits a signal along signal 
wires 334 and 336 to electrical connections 338 and 340 within an 
electrical connector 324 on the proximal hub 308 of the catheter 300. The 
electrical connector is adapted to be connected to an electronic pressure 
monitor which displays an analog or digital indication of the pressure at 
the distal end 332 of the catheter 300. The distal pressure transducer 330 
is preferably a piezoelectric pressure transducer which creates a voltage 
signal indicative of the external fluid pressure exerted on the transducer 
330. Examples of piezoelectric materials suitable for construction of the 
distal pressure transducer 330 include piezoelectric polymers such as 
polyvinylidene bifluoride or Kynar.TM. (Elf Atochem SA), or piezoelectric 
ceramics such as lead barium titanate, zirconium barium titanate or other 
commercially available piezoelectric materials. The geometry of the distal 
pressure transducer 330 may be a ring encircling the distal tip 332 of the 
catheter 300, as shown in FIGS. 7A and 7B. Alternatively, a small patch of 
the piezoelectric material may be mounted on one side of the distal tip 
332 of the catheter 300. The distal pressure transducer 330 preferably has 
a pressure sensing range from about -75 to 300 mmHg or greater (-1.5 to 
5.7 psi) so as to be able to measure root pressure during cardioplegia 
infusion and during venting of the aortic root. 
Optionally, a balloon pressure monitoring transducer 350 may also be 
mounted within the balloon 310 of the catheter 300 for monitoring the 
inflation pressure of the balloon 310. The balloon pressure monitoring 
transducer 350 electronically monitors the balloon inflation pressure and 
transmits a signal along signal wires 352 and 354 to electrical 
connections 356 and 358 within the electrical connector 324 on the 
proximal hub 308 of the catheter 300. The balloon pressure monitoring 
transducer 350 is preferably a piezoelectric pressure transducer which 
creates a voltage signal indicative of the external fluid pressure exerted 
on the transducer 350, made for example from one the piezoelectric 
polymers or piezoelectric ceramics designated above in connection with the 
distal pressure transducer 330. The balloon pressure monitoring transducer 
350 preferably has a pressure sensing range from about -760 to 300 mmHg or 
greater (-15 to 35 psi) so as to be able to measure balloon pressure 
during inflation and deflation of the occlusion balloon 310. The balloon 
pressure monitoring transducer 350 can be used to monitor internal balloon 
pressure to make sure that the occlusion balloon 310 has been inflated to 
proper pressure to insure reliable occlusion of the ascending aorta. The 
balloon pressure monitoring transducer 350 can also be used to determine 
when the occlusion balloon 310 has contacted the interior wall of the 
ascending aorta by monitoring for a spike in the inflation pressure within 
the balloon or for an inflection point in the pressure/volume curve while 
inflating. A safe inflation volume can be determined for each individual 
patient by a protocol wherein the occlusion balloon 310 is inflated until 
it contacts the interior wall of the ascending aorta, then a set volume of 
inflation fluid is added to create a reliable seal to occlude the aortic 
lumen. Alternatively, the protocol for inflation could include determining 
when the occlusion balloon 310 contacts the aortic wall and incrementally 
increasing the pressure a set amount to form a seal. 
The signal wires 334, 336 from the distal pressure transducer 330 and the 
signal wires 352, 354 from the balloon pressure monitoring transducer 350 
may extend through the annular inflation lumen 316 between the inner tube 
302 and the outer tube 304. The signal wires 334, 336, 352, 354 may be 
laid loosely in the inflation lumen 316 with some slack, or they may be 
spiraled around the inner tube 302, so that they do not adversely affect 
the bending characteristics of the catheter 300. Alternatively, the signal 
wires 334, 336, 352, 354 may be embedded in the wall of the inner tube 
302, either during the extrusion process or in a post-extrusion operation. 
In order to have electrical impedance to match the impedance of the 
transducers 330, 350 and/or the electronic pressure monitor, the signal 
wires 334, 336, 352, 354 may be provided as parallel pairs, twisted pairs 
or coaxial cables, as required. 
The use of a distal pressure transducer 330 for monitoring aortic root 
pressure eliminates the need for a separate pressure monitoring lumen in 
the catheter as provided in the embodiments of FIGS. 5A and 6A. This 
allows a reduction in the catheter external diameter without sacrificing 
catheter performance in terms of the cardioplegia flow rate in the 
infusion lumen 312 and the speed of balloon inflation and deflation 
through the balloon inflation lumen 316. A 10 French (3.3 mm external 
diameter) catheter constructed according to this design provides a flow 
rate and balloon inflation performance comparable to a 10.5 French (3.5 mm 
external diameter) catheter constructed with a separate pressure 
monitoring lumen. Reducing the external diameter of the catheter in this 
way has a number of clinical advantages. The smaller diameter catheter 
will be easier to introduce into a patient's femoral, brachial or other 
artery by either the Seldinger technique or by an arterial cutdown or by 
insertion through an introducer sheath. It will also be possible to 
introduce the smaller diameter catheter into smaller arteries, as 
encountered in smaller patients, particularly female and pediatric 
patients. This will increase the clinical applicability of the catheter 
and the method for its use to a greater patient population. In all 
patients, the smaller diameter catheter will cause less trauma to the 
artery it is introduced through, thereby reducing the likelihood of 
complications, such as bleeding or hematoma at the arterial access site. 
The smaller diameter catheter will also be particularly advantageous when 
used in conjunction with the dual function arterial cannula and introducer 
sheath described below in relation to FIGS. 31-34 because the smaller 
diameter shaft will occupy less of the blood flow lumen of the cannula, 
allowing higher blood flow rates at lower pressures. With these 
improvements, the external diameter of an endoaortic partitioning catheter 
for use with warm blood cardioplegia can be reduced to 8 to 10 French 
(2.7-3.3 mm external diameter) and for use with crystalloid cardioplegia 
can be reduced to 7 to 9 French (2.3-3.0 mm external diameter). 
Further improvements in reducing the effective diameter of the catheter 
during introduction or removal of the catheter from the peripheral 
arterial access site can be accomplished by making the occlusion balloon 
self-collapsing around the catheter. Two embodiments of 
coaxial-construction catheters with self-collapsing occlusion balloons are 
shown in FIGS. 8A-8C and 9A-9B. 
FIG. 8A shows a transverse cross section of a coaxial-construction 
endoaortic partitioning catheter 400 in which the inner tube 402 and the 
outer tube 404 are axially movable with respect to one another. The inner 
tube 402 has a cardioplegia infusion lumen 412 and a pressure monitoring 
lumen 414. The inner tube 402 is connected to a first proximal hub 430 
with luer fitting connections 426 and 424 in communication with the 
cardioplegia infusion lumen 412 and the pressure monitoring lumen 414, 
respectively. The outer tube 404 fits coaxially around the inner tube 402 
with an annular space between the two tubes providing a balloon inflation 
lumen 416. The outer tube 404 is connected to a second proximal hub 432 
with a luer fitting connection 422 for the balloon inflation lumen 416. 
The inner tube 402 passes through the second proximal hub 432 exiting 
through a sliding fluid seal 440 that allows axial movement of the inner 
tube 402 with respect to the second proximal hub 432 and the outer tube 
404. 
In one preferred embodiment the sliding fluid seal 440 is a type of 
compression fitting known in the industry as a Tuohy-Borst adapter. The 
Tuohy-Borst adapter 440 has a compressible tubular or ring-shaped 
elastomeric seal 442 that fits within a bore 446 on the proximal end of 
the second proximal hub 432. A threaded compression cap 444 fits onto the 
proximal end of the second proximal hub 432. When the compression cap 444 
is tightened, it compresses the elastomeric seal 442 axially, which causes 
the lumen 448 of the seal 442 to narrow and seal against the inner tube 
402. The Tuohy-Borst adapter 440 can also be used to lock the position of 
the inner tube 402 with respect to the second proximal hub 432 and the 
outer tube 404 by tightening the compression cap 444 until the friction 
between the elastomeric seal 442 and inner tube 402 effectively locks them 
together to prevent axial movement between the two. 
In a second preferred embodiment, shown in FIG. 8D, a sliding fluid seal 
440 is combined with a locking mechanism 450 to lock the inner tube 402 
with respect to the outer tube 404 to prevent axial movement between the 
two. The locking mechanism 450 may comprise a threaded shaft 452 in 
alignment with the inner tube 402 and a lock nut 454 threaded onto the 
shaft 452. By turning the lock nut 454 on the threaded shaft 452, the user 
can adjust the position of the inner tube 402 relative to the outer tube 
404 to increase or decrease the length of the occlusion balloon 410 when 
inflated. The sliding fluid seal 440 may be a Tuohy-Borst adapter as 
described above or, because a separate locking mechanism 450 is provided, 
it may be a simple sliding seal, such as an O-ring or wiper seal 456, as 
illustrated. 
When the balloon 410 is deflated the inner tube 402 can be moved to its 
furthest distal position and locked with respect to the outer tube 404, as 
shown in FIG. 8A. This stretches the wall of the occlusion balloon 410 
collapsing the deflated balloon tightly around the inner tube 402 to 
reduce the deflated profile for easy introduction through the peripheral 
arterial access site or through an introducer sheath. Once the occlusion 
balloon 410 has been advanced to the desired location in the ascending 
aorta, the locking mechanism 440 can be released so that the balloon 410 
can be inflated. FIG. 8B shows the endoaortic partitioning catheter 400 of 
FIG. 1A with the inner tube 402 in an intermediate position with respect 
to the outer tube 404 and the occlusion balloon 410' inflated. In this 
position, the inner tube 402 and the outer tube 404 keeps a tension on the 
ends of the occlusion balloon 410' which elongates the balloon somewhat in 
the axial direction. This results in the balloon 410' having a somewhat 
oblong inflated profile which is smaller in diameter and longer axially 
than the typical spherical shape of a freely inflated balloon. FIG. 8C 
shows the endoaortic partitioning catheter 400 of FIGS. 1A and 1B with the 
inner tube 402 in its farther proximal position with respect to the outer 
tube 404 and the occlusion balloon 410" inflated. In this position, the 
inner tube 402 and the outer tube 404 places a compressive force on the 
ends of the occlusion balloon 410" which restricts the expansion of the 
balloon somewhat in the axial direction. This results in the balloon 410" 
having an inflated profile which achieves the full diameter of a freely 
inflated balloon diameter, but is somewhat shorter in the axial direction. 
This feature allows the user to select the inflated diameter of the 
balloon and the axial length of the balloon, and therefore the length of 
contact with the aortic wall, within certain ranges, as well as allowing 
the balloon to be more fully collapsed when deflated for insertion and 
removal. The range of useful balloon diameters of the occlusion balloon 
410 for use in an adult human ascending aorta is from above 20 to 40 cm. 
Other ranges of balloon diameters may be needed for pediatric patients or 
nonhuman subjects. 
This feature will find particular utility when the endoaortic partitioning 
catheter 400 is used while performing surgery or other interventional 
procedures on the aortic valve, or within the aortic root or ascending 
aorta. To facilitate the surgery, it will be important to provide as much 
clearance as possible between the inflated occlusion balloon 410" and the 
aortic valve to allow manipulation of instruments within the ascending 
aorta while at the same time being sure that the occlusion balloon 410" 
does not occlude the brachiocephalic artery. In this case, the inner tube 
402 would be adjusted to its farthest proximal position with respect to 
the outer tube 404 before the occlusion balloon 410" is inflated in order 
to restrict the size of the balloon 410" as much as possible in the axial 
direction. 
FIG. 9A shows a transverse cross section of a coaxial-construction 
endoaortic partitioning catheter 500 in which the inner tube 502 and the 
outer tube 504 are rotatable with respect to one another. The inner tube 
502 has a cardioplegia infusion lumen 512 connected to a luer fitting 
connection 526 on the proximal hub 508. The outer tube 504 fits coaxially 
around the inner tube 502 with an annular space between the two tubes 
providing a balloon inflation lumen 516 which communicates with a luer 
fitting connection 522 on the proximal hub 508. The outer tube 504 is 
connected to a rotating collar 540 which is rotatably and slidably mounted 
on the distal end of the proximal hub 508. There is an O-ring seal 542 or 
other type of fluid tight seal between the rotating collar 540 and the 
proximal hub 508. An aortic occlusion balloon 510 is mounted on the distal 
end of the catheter 500 with the proximal balloon neck 518 sealingly 
attached to the outer tube 504 and the distal balloon neck 520 sealingly 
attached to the inner tube 502 of the catheter 500 so that the balloon 
inflation lumen 516 communicates with the interior of the balloon 510. The 
occlusion balloon 510 is preferably made of an elastomeric material, such 
as latex, silicone or polyurethane. A piezoelectric distal pressure 
transducer 530 mounted at the distal tip of the catheter 500 
electronically monitors the aortic root pressure and transmits a signal 
along signal wires 532 and 534 to electrical connections 536 and 538 
within an electrical connector 524 on the proximal hub 508 of the catheter 
500. 
In order to collapse the occlusion balloon 510 to its lowest possible 
deflated profile for introduction or withdrawal of the catheter 500 
through a peripheral arterial access site or through an introducer sheath, 
the rotating collar 540 can be rotated with respect to the proximal hub 
508 to twist the deflated occlusion balloon 510 around the inner tube 502. 
In addition, the rotating collar 540 can also be moved proximally with 
respect to the proximal hub 508 to tension the balloon to create an even 
lower deflated profile. After the catheter has been introduced and 
maneuvered to the desired position, the rotating collar 540 is counter 
rotated to release the balloon from its twisted state before inflation. 
The catheter 500 with the fully inflated occlusion balloon 510' is shown 
in FIG. 9B. When the catheter is to be withdrawn after use, the occlusion 
balloon 510 is deflated and the rotating collar 540 is again rotated and 
moved proximally with respect to the proximal hub 508 to twist the 
deflated occlusion balloon 510 around the inner tube 502 to create a lower 
deflated profile for removal of the catheter 500. 
In each of the previously described embodiments, the shaft of the catheter, 
whether it has a coaxial construction or a multilumen construction, may 
take one of a variety of forms. In the simplest form, the shaft of the 
catheter may be a straight length of flexible tubing, made from a highly 
flexible plastic or elastomer, such as polyurethane, polyethylene, 
polyvinylchloride or a polyamide polyether block copolymer, preferably in 
the range of 35 to 72 Shore D durometer. Another variation of this 
embodiment would be to provide a straight shaft with zones of varying 
stiffness graduated from a stiff proximal section to a highly flexible 
distal section. The variable stiffness shaft could be made by welding 
tubing segments of different stiffness polymers end-to-end to create two, 
three or more zones of stiffness. In one illustrative embodiment, the 
catheter shaft could be made with a stiff proximal section of a polyamide 
polyether block copolymer with a hardness of 63 to 72 Shore D durometer, 
an intermediate section of a softer grade of the same polymer with a 
hardness of 55 to 63 Shore D durometer, and a distal section of a very 
soft grade of the polymer with a hardness of 35 to 55 Shore D durometer. 
In addition, an especially flexible soft tip with a hardness of 25 to 35 
Shore D durometer may be molded or heat bonded to the distal end of the 
catheter shaft. Alternatively, the shaft can be made with continuously 
graduated stiffness from the proximal to distal end using a process such 
as total intermittent extrusion to gradually change the stiffness along 
the length of the catheter shaft. In a coaxial-construction catheter 
either or both of the inner tube and the outer tube may be made with 
varying stiffness to achieve the overall effect of a graduated stiffness 
catheter. Furthermore, either or both of the inner tube and the outer tube 
may be reinforced with wire or filament braiding or coils for increased 
stiffness, torque control or kink resistance. 
The polymeric material of the shaft is preferably loaded with a radiopaque 
filler, such as bismuth subcarbonate, bismuth oxychloride, bismuth 
trioxide, barium sulfate or another radiopaque material. The shaft is 
preferably loaded with a level of between about 10 and 30 percent of 
radiopaque filler by weight, preferably about 20%. The soft tip may be 
loaded with a higher percent of radiopaque filler, such as about 30 to 35 
percent by weight for greater fluoroscopic visibility. Instead of or in 
addition to the radiopaque filler, radiopaque markers, for example rings 
of gold, platinum, tin, tantalum or tungsten alloys may be attached to the 
catheter shaft at various points along the length, especially at the tip 
of the catheter for fluoroscopic visibility. 
In such an embodiment, the highly flexible catheter would be advanced 
through the patient's descending aorta and into the ascending aorta with a 
stiffer guidewire and/and or a dilator placed in the infusion lumen of the 
catheter to provide stiffness for advancing and maneuvering the catheter 
into position. 
With the varying stiffness embodiment, the stiffness of the proximal shaft 
segment will assist in advancing and maneuvering the catheter into 
position. If desired, a curved guidewire or dilator may be used to assist 
in forming the catheter shaft to catheter shaft to the curve of the aortic 
arch. Once the catheter balloon would be inflated to occlude the ascending 
aorta and the guidewire or dilator withdrawn to free the infusion lumen 
for infusing cardioplegic fluid. 
In another approach, the catheter shaft may be made of a somewhat stiffer 
polymer so that the distal segment of the catheter can be precurved to a 
configuration that assists in maneuvering the occlusion balloon into the 
correct position within the ascending aorta. As with the straight catheter 
shaft previously described, the precurved catheter shaft may also be made 
with varying degrees of stiffness graduated from a stiff proximal segment 
to a flexible distal segment. The shaft would be made of slightly higher 
durometer grades of a flexible plastic or elastomer, such as polyurethane, 
polyethylene, polyvinylchloride or a polyamide polyether block copolymer, 
preferably in the range of 55 to 72 Shore D durometer. A short, very 
flexible tip of a low durometer polymer, preferably in the range of 25 to 
35 Shore D durometer, can be added to the distal end to make it less 
traumatic to the arterial walls and the aortic valve which it may come in 
contact with. Two variations of precurved catheter shafts are shown in 
FIGS. 10A-10C and 11A-11C. For the purposes of illustration, these 
embodiments are shown as built in a multilumen construction, but the 
precurved shafts can as well be made in one of the coaxial constructions 
previously described. 
One preferred embodiment of an aortic partitioning catheter 600 with a 
precurved shaft is shown in FIG. 10A. In this embodiment the distal 
portion 604 of the catheter shaft 602 is configured to facilitate 
placement of the occlusion balloon 610 into the ascending aorta. The curve 
of the catheter shaft 602 also stabilizes the catheter in the proper 
position to prevent migration or dislodgement of the inflated occlusion 
balloon. The distal portion 604 of the catheter shaft 602 has a curve of 
approximately 270-300 degrees of arc. The curve of the catheter shaft 602 
is a compound curve having a first segment 606 of approximately 
135.degree. of arc with a radius of curvature of approximately 75-95 mm. 
Contiguous with the first segment is a second segment 608 of approximately 
135.degree. of arc with a tighter radius of curvature of approximately 
40-50 mm. Continuing from the second segment is a third segment 612 of 
approximately 25-50 mm in length adjacent to the distal end 614 of the 
catheter. The occlusion balloon 610 is mounted on the third segment 612 of 
the catheter shaft near the distal end 614 of the catheter 600. The third 
segment 612 of the catheter 600 may be straight, so that the total arc 
subtended by the catheter curve 604 is approximately 270.degree.. 
Alternatively, the third segment 612 of the catheter 600 may be angled 
upward at a point about midway along the third segment 612, as shown in 
FIG. 10A, creating a total arc of curvature of about 300.degree.. The 
upward angle of the third segment 612 helps the catheter 600 to follow a 
dilator or guidewire as it passes over the curve of the aortic arch during 
catheter introduction. The angle of the third segment 612 also helps to 
prevent the distal tip 614 of the catheter 600 from contacting the 
interior wall of the aorta as it passes over the aortic arch thereby 
reducing the likelihood of irritating or damaging the aortic wall or of 
dislodging calculi or other sources of potential emboli. The curve of the 
catheter is generally coplanar, as shown in the side view in FIG. 10B. The 
specifics of this catheter curve are given as an illustrative example of 
one preferred embodiment. The precise angles and lengths of the curve may 
be varied according to the geometry of the patient's anatomy based on 
fluoroscopic observation of the aortic arch. 
A cross section of the catheter shaft is shown in FIG. 10C. The catheter 
shaft 602 is made from a multilumen extrusion of a flexible plastic or 
elastomer, such as polyurethane, polyethylene, polyvinylchloride or a 
polyamide polyether block copolymer, preferably in the range of 55 to 72 
Shore D durometer. In one preferred embodiment, the multilumen catheter 
shaft 602 has a cardioplegia infusion lumen 616, a distal pressure 
monitoring lumen 618, and a balloon inflation lumen 620. The balloon 
inflation lumen 620 is in fluid communication with the interior of the 
inflatable occlusion balloon 610. The infusion lumen 616 and the distal 
pressure monitoring lumen 618 each connect with separate ports at or near 
the distal tip 614 of the catheter 600, distal to the occlusion balloon 
610. For use with blood/cardioplegia techniques, the catheter shaft 602 
preferably has an external diameter of 3.5 to 4 mm or 10.5 to 12 French 
(Charriere scale). For use with crystaloid cardioplegia techniques, the 
catheter shaft 602 may be made smaller, with an external diameter of 3.3 
mm or 10 French (Charriere scale) or smaller. 
FIG. 11 is a schematic partly cut-away representation of a patient's aortic 
arch A with the endoaortic partitioning catheter 600 of FIG. 10A 
positioned in the ascending aorta B. In use, the distal curve 604 in the 
catheter shaft 602 of FIG. 10A is initially straightened out by inserting 
a guidewire and a dilator (not shown) into the infusion lumen 616 of the 
catheter 600 to facilitate insertion of the catheter 600 into a peripheral 
arterial access site such as the femoral artery. The catheter 600 is 
advanced until the distal end 614 of the catheter 600 is at the apex of 
the aortic arch A. Then, the dilator is withdrawn as the catheter 600 is 
advanced over the aortic arch A to allow the curved distal portion 604 of 
the catheter 600 to resume its curve within the ascending aorta B. When 
the catheter 600 is in proper position in the ascending aorta B, the 
second segment 608 of the curved shaft conforms to the aortic arch A to 
hold the distal tip 614 of the catheter centered just above the aortic 
root R. The first curved segment 606 of the catheter shaft resides in the 
descending aorta D, somewhat straightened by its contact with the aortic 
walls. If the patient has a relatively straight ascending aorta B, as 
observed fluoroscopically, a straight third segment 612 of the curved 
shaft is preferred for proper centering of the catheter tip 614 when the 
occlusion balloon 610' is inflated. If the ascending aorta B is curved, a 
curved or angled distal segment 612, such as the one illustrated in FIG. 
10A, is preferred. 
Another preferred embodiment of an aortic partitioning catheter 650 with a 
precurved shaft is shown in FIG. 12A. In this embodiment also the distal 
portion 654 of the catheter shaft 652 is configured to facilitate 
placement of the occlusion balloon 660 into the ascending aorta and to 
stabilize the catheter in the proper position to prevent migration or 
dislodgement of the inflated occlusion balloon 660', but with a slightly 
different geometry to accommodate variations in the patient's anatomy. The 
distal portion 654 of the catheter shaft 652 has an approximately 
elliptical curve which subtends approximately 270-300 degrees of arc. The 
minor axis 646 of the ellipse is parallel to the shaft 652 of the catheter 
and has a length of about 50 to 65 mm. The major axis 648 of the ellipse 
is perpendicular to the shaft 652 of the catheter and has a length of 
about 55 to 70 mm. The elliptical curve can also be viewed as having a 
first segment 656 with a larger radius of curvature, a second segment 658 
with smaller radius of curvature and a third segment 662 on which the 
occlusion balloon 660 is mounted. The curved distal portion 654 of the 
catheter 650 is somewhat out of plane with the catheter shaft, angling or 
spiraling anteriorly from the plane of the catheter shaft by about 
10.degree.-20.degree., as shown in FIG. 12B. In one presently preferred 
embodiment, the distal tip 664 of the catheter 650 has an offset 672 from 
the plane of the catheter shaft 652 of approximately 14 mm. The offset 672 
of the spiral curve helps to center the catheter tip 664 within the 
ascending aorta in patients in whom the ascending aorta is angled 
anteriorly. The preferred degree of offset 672 can vary significantly 
depending on patient anatomy, with an anticipated range of from 0 to 25 mm 
of offset 672 to accommodate most patients. Again, this catheter curve is 
given as an example of one preferred embodiment. The precise angles and 
lengths of the curve should be chosen according to the geometry of the 
patient's anatomy based on fluoroscopic observation of the aortic arch. 
Providing the catheters in a family of curves which are variations of the 
curves shown in FIGS. 10A and 12A, etc. will allow the user to select the 
proper catheter curve for the patient after observing the geometry of the 
aorta fluoroscopically. 
A cross section of the catheter shaft is shown in FIG. 12C. The catheter 
shaft 652 is made from a multilumen extrusion of a flexible plastic or 
elastomer, such as polyurethane, polyethylene, polyvinylchloride or a 
polyamide polyether block copolymer, preferably in the range of 55 to 72 
Shore D durometer. In this illustrative embodiment, the multilumen 
catheter shaft 652 has a cardioplegia infusion lumen 666, a distal 
pressure monitoring lumen 668, and a balloon inflation lumen 670. The 
balloon inflation lumen 670 is in fluid communication with the interior of 
the inflatable occlusion balloon 660. The infusion lumen 666 and the 
distal pressure monitoring lumen 668 each connect with separate ports at 
or near the distal tip of the catheter 664, distal to the occlusion 
balloon 660. The catheter shaft 652 can be made in a range of sizes, for 
instance with an external diameter of 3.5 to 4 mm or 10.5 to 12 French 
(Charriere scale) for use with blood/cardioplegia techniques, or with an 
external diameter of 3.3 mm or 10 French (Charriere scale) or smaller for 
use with crystaloid cardioplegia techniques. 
FIG. 13 is a schematic partly cut-away representation of a patient's aortic 
arch A with the endoaortic partitioning catheter 650 of FIG. 12A 
positioned in the ascending aorta B. In use, a guidewire and a dilator 
(not shown) are inserted into the infusion lumen 666 to straighten out the 
distal curve 654 of the catheter 650. The catheter 650 is introduced into 
a peripheral arterial access site such as the femoral artery and advanced 
until the distal end 664 of the catheter 650 is at the apex of the aortic 
arch A. Then, the dilator is withdrawn as the catheter is advanced over 
the aortic arch A to allow the distal portion 652 of the catheter 650 to 
resume its curve within the ascending aorta B. When the catheter 650 is in 
proper position in the ascending aorta B, the second segment 658 of the 
curved shaft conforms to the aortic arch A to hold the distal tip 664 of 
the catheter centered just above the aortic root R. Due to its curvature, 
the second segment 658 of the catheter shaft tends to hug the inside curve 
of the aortic arch A which helps to prevent the catheter shaft from 
occluding or interfering with blood flow into the brachiocephalic artery 
or other arteries which have their takeoff from the aortic arch. The first 
curved segment 656 of the catheter shaft 652 resides in the descending 
aorta D, somewhat straightened by its contact with the aortic walls. The 
angled or spiral curve of the catheter shaft 652 assists in centering the 
distal tip 664 of the catheter 650 within the lumen of the ascending aorta 
B which is often angled anteriorly within the patient. 
In order to reduce the external diameter of the catheter shaft in the 
embodiments of FIGS. 10A-10C and 12A-12C, particularly for use in 
conjunction with the dual purpose arterial cannula and introducer sheath 
described below in reference to FIGS. 31-34, while maintaining the maximum 
flow rate performance in the catheter, it is desirable to reduce the wall 
thickness of the multilumen extrusion as much as possible. In order to 
improve the kink resistance of the thin-walled catheter shaft in the 
precurved distal portion (604 in FIG. 10A, 654 in FIG. 12A) it has been 
found to be advantageous to dip coat the precurved distal portion with a 
soft, flexible polymer. For example a coating approximately 0.005-0.020 
inches thick of a polyurethane with a hardness of 80 Shore A durometer on 
the precurved distal portion of the catheter shaft has been shown to 
significantly improve the kink resistance of the catheter shaft. If the 
coating is applied before mounting the polyurethane occlusion balloon on 
the catheter shaft, the coating also improves the heat bondability of the 
occlusion balloon to the shaft. Coating only the distal portion of the 
catheter shaft has the advantage that it does not increase the external 
diameter of the catheter shaft in the proximal portion which will reside 
within the blood flow lumen of the dual purpose arterial cannula and 
introducer sheath during perfusion. Since the proximal portion of the 
catheter shaft is not precurved and because it resides in the relatively 
straight descending aorta during use, it is not necessary to fortify the 
kink resistance of the shaft in this region. 
One important function of the catheter curves shown in FIGS. 10A and 12A is 
for centering the tip of the catheter within the ascending aorta before 
and after the occlusion balloon is inflated to insure even distribution of 
the cardioplegic fluid to the coronary arteries when it is injected 
through the infusion lumen into the aortic root. In many cases, the 
compound curve of the catheter is needed to maintain the catheter tip 
within the center of the aortic lumen. It has been found that in some 
cases a simple 180.degree. U-shaped curve results in off-center placement 
of the catheter tip despite the concentricity of the inflated balloon 
because of the curve of the ascending aorta. Another approach to centering 
the distal tip of the catheter within the lumen of the ascending is 
illustrated by the embodiment of the aortic partitioning catheter 700 
shown in FIG. 14. 
FIG. 14 is a front view of an embodiment of the endoaortic partitioning 
catheter 700 having an eccentric aortic occlusion balloon 710. The 
occlusion balloon has a symmetrical deflated profile, shown by solid lines 
710. The asymmetrical inflated profile, shown by phantom lines 710', is 
achieved by molding the occlusion balloon with a thicker wall 712 on one 
side of the balloon 710. The thicker wall 712 of the balloon is oriented 
toward the inside of the distal curve 704 when mounted on the catheter 
shaft 702. When the occlusion balloon 710' is inflated, the thicker wall 
712 resists expansion while the thinner wall 714 of the balloon more 
easily expands to its full potential, resulting in the intended eccentric 
inflated balloon profile 710'. One preferred method for manufacturing the 
occlusion balloon 710 of FIG. 14 is by a two-stage dip molding process. In 
the first stage of the process, a balloon mold, in the form of a dipping 
mandrel having the desired interior shape of the balloon, is oriented 
vertically and dipped into a solution or a suspension containing an 
elastomeric balloon material, such as polyurethane, silicone or latex. 
This creates a relatively even coating of the balloon material over the 
surface of the mandrel. This first coating 706 is then allowed to dry on 
the mandrel. Once the first coating 706 is dry, the orientation of the 
dipping mandrel is rotated to a horizontal position and one side of the 
balloon mandrel is dipped into the elastomer solution to create a second 
coating 708 of balloon material on one side of the balloon 710. The 
balloon mandrel is held in the horizontal orientation until the solvent 
evaporates from the elastomer solution. If the elastomer used to mold the 
balloon 710 is a thermoplastic elastomer, such as a thermoplastic 
polyurethane, the balloon can be removed from the dipping mandrel once it 
has dried. If the elastomer is a thermoset material, such as latex, 
silicone, or a thermoset polyurethane, further curing of the material may 
be required before the balloon 710 can be removed from the dipping 
mandrel. It should be noted that the second coating 708 on the balloon 710 
may be made of a different material from the first coating 706. For 
instance, a stronger or less distensible material may be used for the 
second coating 708 to increase the resistance of the thicker wall 712 of 
the balloon 710 to inflation. It should also be noted that molding each 
coating of the balloon may require multiple iterations of the dipping and 
drying steps, depending on the composition and concentration of the 
polymer solution. For example, the currently preferred process for 
manufacturing polyurethane balloons typically requires about 6-8 
iterations of the dipping and drying steps to make a finished balloon with 
a wall thickness of approximately 0.005-0.020 inches. 
As discussed herein, the catheter shaft 702 is coupled to a source of 
cardioplegic fluid 711, for delivering cardioplegic fluid to arrest the 
patient's heart, and a source of inflation fluid 713 for inflating the 
balloon 710. 
FIGS. 15 and 16 illustrate how an eccentric balloon, like the eccentric 
occlusion balloon 710 of the catheter embodiment of FIG. 14, operates to 
center the tip of the aortic partitioning catheter within the ascending 
aorta of a patient. FIG. 15 is a schematic partly cut-away representation 
of a patient's aortic arch A with an endoaortic partitioning catheter 720 
having a concentric occlusion balloon 722 positioned in the ascending 
aorta B. The endoaortic partitioning catheter 720 has a 180.degree. 
U-shaped catheter curve 724 with a concentric occlusion balloon 722 
mounted on a straight distal portion 726 of the catheter 720. FIG. 15 
shows the effect of placing the U-shaped catheter curve into a patient 
having a curved ascending aorta B. Note how, when the catheter 720 is 
pulled proximally to stabilize the catheter within the aortic arch A, the 
distal end 728 of the catheter is not centered in the aortic lumen despite 
the concentricity of the balloon 722 because of the mismatch between the 
catheter curve and the curve of the ascending aorta B. 
FIG. 16 is a schematic partly cut-away representation of a patient's aortic 
arch A with an endoaortic partitioning catheter 730 having an eccentric 
occlusion balloon 732 positioned in the ascending aorta B. The aortic 
partitioning catheter 730 has a U-shaped distal curve 734 which subtends 
an arc of approximately 180.degree..+-.45.degree.. Mounted on a straight 
distal portion 736 of the catheter shaft is an occlusion balloon 732 
which, when inflated, has an eccentric balloon profile with the larger 
portion 740 of the balloon facing the outside of the catheter curve 734 so 
that it will be oriented toward the right side of the patient. The 
eccentric inflated profile of the balloon 732 assists in centering the 
distal tip 738 of the catheter 730 within the aortic lumen when the 
ascending aorta B is curved. Note how the eccentric balloon 732 
compensates for the mismatch between the catheter curve and the curve of 
the ascending aorta B to result in the distal tip 738 of the catheter 730 
being well centered in the aortic lumen just above the aortic root R. 
FIG. 17 shows an alternative construction for an occlusion balloon 742 with 
an eccentric inflated profile 742'. In this embodiment, the elastomeric 
balloon 742 is molded on a dipping mandrel which is machined with an 
asymmetrical profile. In contrast to the previous example, the molded 
balloon 742 has a uniform wall thickness, but it has an asymmetrical 
deflated profile with a larger side 744 and a smaller side 746. The 
balloon 742 is mounted on the catheter with the larger side 744 oriented 
toward the outside of the distal curve 748 of the catheter 750. When 
inflated, the larger side 744 of the balloon expands to a greater radius 
744' than the smaller side 746', giving the intended eccentric inflated 
profile, as shown by phantom lines 742'. 
FIGS. 18A and 18B show another alternative construction for an occlusion 
balloon 752 with an eccentric inflated profile 752'. In this embodiment, 
the elastomeric occlusion balloon 752 is mounted on the catheter 760 in 
such a way that the side 754 of the balloon oriented toward the inside of 
the distal curve 758 of the catheter is bonded directly to the catheter 
shaft 756 along the length of the balloon 752 using a suitable adhesive. 
When the occlusion balloon 752 is inflated, only the side of the balloon 
oriented toward the outside of the distal curve 758 of the catheter shaft 
is allowed to expand, creating an eccentric inflated balloon profile, as 
shown by phantom lines 752'. 
FIGS. 19A-19D and 20A-20D show alternative constructions of an eccentric 
occlusion balloon made of a nondistensible balloon material, such as 
polyethylene, polyethylene terephthalate polyester, polyester copolymers, 
polyamide or polyamide copolymers. Using a nondistensible balloon material 
such as these allows more precise control over the final shape and 
dimensions of the inflated occlusion balloon, as compared to the 
elastomeric balloons previously described. The nondistensible balloons can 
be thermoformed from tubing extruded from a nonelastomeric polymer, using 
known methods. Alternatively, the balloons can be dipped or rotomolded of 
a nonelastomeric polymer in solution. It is presently preferred to mold 
the inelastic balloon material using a hollow or negative mold of the 
exterior inflated balloon shape rather than a positive mold of the 
interior shape as used for the elastomeric balloons, because the molded 
inelastic balloons may be difficult to remove from a positive mold. 
FIGS. 19A-19D show a first example of a nondistensible eccentric occlusion 
balloon 762. FIG. 19A shows a side view of the occlusion balloon in the 
deflated state 762 and inflated state 762'. FIG. 19B shows an end view of 
the same occlusion balloon in the deflated 762 and inflated states 762'. 
The occlusion balloon 762 is molded in an asymmetrical shape with a large 
side 764 and a smaller side 766. The occlusion balloon 762 is mounted on 
the catheter shaft 768 with the larger side 764 oriented toward the 
outside of the distal curve of the catheter. The occlusion balloon tends 
to flatten out, as shown by solid lines 762, when it is deflated. In order 
to reduce the deflated profile of the balloon for introduction into a 
peripheral artery, the flattened balloon 762" is wrapped around the 
catheter shaft 768 as shown in a side view in FIG. 19C and an end view in 
FIG. 19D. 
FIGS. 20A-20D show a second example of a nondistensible eccentric occlusion 
balloon 780. FIG. 20A shows a side view of the occlusion balloon in the 
deflated state 780 and inflated state 780'. FIG. 20B shows an end view of 
the same occlusion balloon in the deflated state 780 and inflated state 
780'. The occlusion balloon 780 is molded in an asymmetrical shape with a 
large side 782 and a smaller side 784. The occlusion balloon 780 is 
mounted on the catheter shaft 786 with the larger side 782 oriented toward 
the outside of the distal curve of the catheter. In this embodiment, the 
smaller side 784 of the occlusion balloon is adhesively bonded to the 
catheter shaft 786 along the length of the balloon 780 so that the 
inflated balloon 780' expands only toward the outside of the distal curve 
of the catheter. The occlusion balloon flattens out, as shown by solid 
lines 780, when it is deflated. In order to reduce the deflated profile of 
the balloon for introduction into an artery, the flattened balloon 780" is 
wrapped around the catheter shaft as shown in a side view in FIG. 20C and 
an end view in FIG. 20D. 
The eccentrically shaped occlusion balloons of FIGS. 14 and 16-20 serve to 
help center the distal tip of the aortic partitioning catheter within the 
ascending aorta for uniform distribution of cardioplegic fluid injected 
through the infusion lumen and for aligning the tip of the catheter with 
the center of the aortic valve when other instruments are introduced 
through the infusion lumen. The degree of concentricity of the occlusion 
balloon can be varied from perfectly concentric to completely eccentric, 
or one-sided, using the embodiments and methods described in connection 
with FIGS. 14 and 16-20. Specially shaped occlusion balloons can also be 
used with the aortic partitioning catheter of the present invention for 
maximizing the working space within the ascending aorta between the aortic 
valve and the occlusion balloon. This aspect of the invention will be of 
particular significance when the catheter system is used for arresting the 
heart so that surgery or other interventional procedures can be performed 
on the patient's aortic valve. Whether the aortic valve surgery is 
performed by thoracoscopic methods, endovascular methods or open chest 
surgical methods, it will be beneficial to be able to occlude the 
ascending aorta as required for establishing cardiopulmonary bypass 
without obstructing surgical access to the aortic valve. This aspect of 
the invention will also find particular utility when performing 
port-access CABG surgery with a saphenous vein bypass graft or other free 
graft which must be anastomosed to the ascending aorta because the 
occlusion balloon will not interfere with the anastomosis procedure. FIGS. 
21-24 show four variations of specially shaped balloons developed for this 
purpose. These balloons can be manufactured from elastomeric materials or 
from nondistensible, inelastic materials as previously described. 
FIG. 21 is a schematic partly cut-away representation of a patient's aortic 
arch A with a first variation of an endoaortic partitioning catheter 790 
having a shaped occlusion balloon 792 positioned in the ascending aorta B. 
The occlusion balloon 792 has a generally cylindrical outer geometry that 
has been modified by curving it to match the curvature of the aortic arch 
A. Thus, the surface of the occlusion balloon facing the outside curve of 
the aortic arch A has a convex curvature 794 to match the concave 
curvature of the aortic wall at that point and the surface of the 
occlusion balloon facing the inside curve of the aortic arch A has a 
concave curvature 796 to match the convex curvature of the opposite aortic 
wall. The geometry of the occlusion balloon 792 is further modified by 
molding a groove or indentation 798 into the proximal edge of the convexly 
curved outer surface 794 of the balloon 792. The indentation 798 is 
positioned to allow blood flow past the occlusion balloon 792 into the 
brachiocephalic artery C. This allows the occlusion balloon 792 of the 
aortic partitioning catheter 790 to be placed as far downstream in the 
ascending aorta as possible without occluding flow to the brachiocephalic 
artery C from the cardiopulmonary bypass system. The working space between 
the aortic valve V and the occlusion balloon 792 is maximized to allow 
maneuvering of surgical instruments, interventional catheters or a valve 
prosthesis within the ascending aorta B. Although it does not serve to 
occlude the aortic lumen, the proximal portion of the occlusion balloon 
792 contacts the aortic wall and helps to stabilize the inflated balloon 
within the aorta to keep the distal end of the catheter centered and to 
help prevent unintended displacement of the inflated balloon. 
FIG. 22 is a schematic partly cut-away representation of a patient's aortic 
arch A with a second variation of an endoaortic partitioning catheter 800 
having a shaped occlusion balloon 802 positioned in the ascending aorta B. 
As in the previous example, the occlusion balloon 802 has a generally 
cylindrical outer geometry that has been modified by curving it to match 
the curvature of the aortic arch A. The surface of the occlusion balloon 
facing the outside curve of the aortic arch A has a convex curvature 804 
to match the concave outer curvature of the aortic wall and the surface of 
the occlusion balloon facing the inside curve of the aortic arch A has a 
concave curvature 806 to match the convex inner curvature of the opposite 
aortic wall. The geometry of the occlusion balloon 802 is further modified 
by molding a large ramp-shaped indentation 808 into the proximal side of 
the convexly curved outer surface 804 of the balloon 802. The wall of the 
occlusion balloon 802 can be adhesively attached to the catheter shaft 810 
along the length of the ramp-shaped indentation 808 to help maintain the 
geometry of the balloon when subjected to inflation pressure. The 
ramp-shaped indentation 808 is positioned to allow blood flow past the 
occlusion balloon 802 into the brachiocephalic artery C. This allows the 
occlusion balloon 802 of the aortic partitioning catheter 800 to be placed 
as far downstream in the ascending aorta as possible without occluding 
flow to the brachiocephalic artery C in order to maximize the working 
space between the aortic valve V and the occlusion balloon 802. The broad 
ramp-shaped indentation 808 in the occlusion balloon 802 lessens the need 
for careful placement of the occlusion balloon 802 with respect to the 
brachiocephalic artery C without danger of occluding it. The concavely 
curved inner surface 806 of the occlusion balloon 802 provides an extended 
contact surface with the wall of the aortic arch A to stabilize the 
inflated occlusion balloon 802 and to discourage unintended movement or 
dislodgement of the occlusion balloon 802. As in the previous embodiment, 
the proximal portion of the occlusion balloon 802 contacts the aortic wall 
and helps to stabilize the inflated balloon within the aorta to keep the 
distal end of the catheter centered and to help prevent unintended 
displacement of the inflated balloon. 
FIG. 23A is a schematic partly cut-away representation of a patient's 
aortic arch A with a third variation of an endoaortic partitioning 
catheter 820 having a shaped occlusion balloon 812 positioned in the 
ascending aorta B. FIG. 23B is a transverse cross section of the shaped 
occlusion balloon of FIG. 23A. This occlusion balloon 812 also has a 
generally cylindrical outer geometry that has been modified by curving it 
to match the curvature of the aortic arch A. The surface of the occlusion 
balloon facing the outside curve of the aortic arch A has a convex 
curvature 814 to match the concave outer curvature of the aortic wall and 
the surface of the occlusion balloon facing the inside curve of the aortic 
arch A has a concave curvature 816 to match the convex inner curvature of 
the opposite aortic wall. The geometry of the occlusion balloon 812 is 
further modified by molding an extended groove or invagination 818 into 
the proximal side of the convexly curved outer surface 814 of the balloon 
812. The extended groove 818 should have a width at least as wide as the 
ostium of the brachiocephalic artery C. The wall of the occlusion balloon 
812 can be adhesively attached to the catheter shaft 822 along the length 
of the extended groove 818 to help maintain the geometry of the balloon 
when subjected to inflation pressure. The extended groove 818 is 
positioned to allow blood flow past the occlusion balloon 812 into the 
brachiocephalic artery C. This allows the occlusion balloon 812 of the 
aortic partitioning catheter 800 to be placed even farther downstream in 
the ascending aorta without occluding flow to the brachiocephalic artery C 
in order to maximize the working space between the aortic valve V and the 
occlusion balloon 812. Again, the concavely curved inner surface 816 of 
the occlusion balloon 812 provides an extended contact surface with the 
wall of the aortic arch A to stabilize the inflated occlusion balloon 812 
and to discourage unintended movement or dislodgement of the occlusion 
balloon 812. 
FIG. 24 is a schematic partly cut-away representation of a patient's aortic 
arch A with a fourth variation of an endoaortic partitioning catheter 824 
having a shaped occlusion balloon 826 positioned at the apex of the aortic 
arch A. In an effort to further maximize the working space between the 
aortic valve V and the occlusion balloon 826 the geometry of the occlusion 
balloon 826 has been modified so that it can be placed at the very apex of 
the aortic arch A without compromising blood flow to the brachiocephalic, 
common carotid or subclavian arteries. The occlusion balloon 826 has a 
generally cylindrical outer geometry modified with a helical groove 830 
that starts at the proximal end 834 of the balloon and spirals around the 
balloon 826 in the distal direction. In this illustrative embodiment, the 
spiral groove 830 forms approximately two complete turns encircling the 
occlusion balloon 826 and is delimited by an annular ring 828 that forms a 
seal with the aortic wall at the distal end of the balloon 826 to isolate 
the heart and the coronary arteries the systemic blood flow which is 
supported by the cardiopulmonary bypass system. The spiral groove 830 
forms a flow path for oxygenated blood from the descending aorta to the 
brachiocephalic, common carotid or subclavian arteries C. A spiral ridge 
832 that runs along the spiral groove 830 contacts the aortic wall and 
stabilizes the inflated occlusion balloon 826 to prevent unintended 
movement of the occlusion balloon 812 without occluding blood flow to the 
head and neck arteries. This same effect can be accomplished using 
functionally equivalent balloon geometries. For instance, this effect 
could be achieved with a shaped balloon having an annular ring at the 
distal end of the balloon to seal against the aortic wall, isolating the 
heart and the coronary arteries from systemic blood flow, and a 
multiplicity of bumps or ridges at the proximal end to contact the aortic 
wall and stabilize the balloon, with the space between the bumps providing 
a blood flow path to the head and neck arteries branching from the aortic 
arch. 
Another aspect of the present invention is illustrated in FIGS. 25A and 
25B. In this embodiment, the function of de-airing the heart and the 
ascending aorta at the completion of the interventional procedure has been 
combined with the endoaortic partitioning catheter 130. The catheter 130 
is configured so that the distal tip 131 of the catheter is positioned 
near the anterior wall of the ascending aorta B. This can be accomplished 
by making a curve 132 in the distal portion of the catheter shaft that 
brings the tip 131 of the catheter near the anterior wall of the ascending 
aorta B, as shown in FIG. 25A. Alternatively, the occlusion balloon 134 
can be shaped so that when the balloon 134 is inflated, the distal tip 135 
of the catheter 133 is directed toward the anterior wall of the ascending 
aorta B, as shown in FIG. 25B. The advantage of this modification of the 
endoaortic partitioning catheter is that, when the patient is placed in a 
supine position, the distal tip of the catheter is at the highest point in 
the ascending aorta so that any air bubbles that enter the heart, the 
coronary arteries or the aortic root during the course of surgery can be 
vented out through a lumen in the catheter prior to deflating the 
occlusion balloon to reverse the cardioplegic arrest 
FIG. 26 shows another application of shaped balloons for the purpose of 
centering the tip 137 of the endoaortic partitioning catheter 136 within 
the ascending aorta B. The expandable occlusion balloon 138 has a distal 
occlusion means 139 with an expanded diameter sufficient to occlude the 
ascending aorta B and a proximal stabilizing means 140 with an expanded 
diameter sufficient to contact the inner surface of the ascending aorta B. 
Between the occlusion means 139 and the stabilizing means 140 is an area 
of reduced diameter 141. When expanded, the occlusion means 139 blocks 
substantially all systolic and diastolic blood flow through the ascending 
aorta B. The stabilizing means 140 contacts the inner surface of the 
ascending aorta B and orients the distal segment 142 of the catheter shaft 
so that it is parallel with the axis of the ascending aorta B, reliably 
centering the catheter tip 143 within the aortic lumen just superior to 
the aortic root R. 
One particular embodiment for achieving this geometry is shown in FIG. 26. 
In this embodiment, the occlusion balloon 138 has a dumbbell shape when 
expanded. The occlusion means is provided by a distal lobe 139 of the 
dumbbell shaped balloon 138, and the stabilizing means is provided by a 
proximal lobe 140 of the balloon, with a waist 141 of reduced diameter 
between the proximal 140 and distal 139 lobes. The dumbbell shaped 
occlusion balloon 138 thus has two rings of contact with the inner surface 
of the ascending aorta B for better stabilization and orientation of the 
balloon in the proper position. Additional advantages of this 
configuration are that by providing two rings of contact with the inner 
surface of the ascending aorta B, the dumbbell shaped balloon 138 can 
achieve a better and more reliable seal and greater resistance to 
displacement of the inflated balloon. 
Another particular embodiment for achieving a similar geometry would have 
two separate, but closely spaced, expandable balloons mounted on the 
distal segment of the catheter shaft. When expanded, the more distal 
balloon serves as an occlusion means, and the more proximal balloon serves 
as a stabilizing means for orienting the distal segment of the catheter 
parallel to the axis of the aortic lumen. It should be noted that the 
stabilizing means need not occlude the ascending aorta. However, for 
proper effect, it should contact the inner surface of the ascending aorta 
at at least three points around the inner circumference of the ascending 
aorta. Thus, the stabilizing means may have other non-spherical geometries 
that do not fully occlude the ascending aorta. For instance, multiple 
smaller balloons could be mounted circumferentially around the catheter 
shaft so that, when the balloons are inflated, they contact the inner 
surface of the ascending aorta at at least three points. Likewise, an 
expandable, non-balloon stabilizing means can also be used for contacting 
the inner surface of the ascending aorta for stabilizing and orienting the 
distal tip of the catheter. 
Another approach to centering the distal tip of the endoaortic partitioning 
catheter within the ascending aorta, shown in FIG. 27, works independently 
of balloon geometry. In this embodiment, the distal tip 145 of the 
endoaortic partitioning catheter 144 is made steerable by one or more 
control wires 146, 147 extending from the proximal end of the catheter 144 
to the distal end through one or more lumens in the side wall of the 
catheter shaft 148. The distal end of the control wires 146, 147 connect 
to a rigid ring or other anchoring device embedded in the wall of the 
catheter shaft 148 near the distal tip 145 of the catheter 144. The 
proximal end of the control wires 146, 147 connect to a control means 149 
at the proximal end of the catheter. For catheters 144 having one degree 
of freedom (i.e. 1-2 control wires) in the steerability of the distal tip 
145, the control means 149 can be a control knob or lever or similar 
control device. For catheters 144 having two degrees of freedom (i.e. 4 or 
more control wires) in the steerability of the distal tip 145, the control 
means 149 can be a joy stick or similar control device. The shaft 148 of 
the catheter should be made with a flexible distal segment 150 which is 
relatively more flexible than the proximal portion of the catheter shaft 
148. This concentrates the deflection of the catheter shaft in the distal 
section 150 when one or more of the control wires 146, 147 are tensioned 
by the control means 149 to steer the distal tip 145 of the catheter 144. 
The steering mechanism can be used to deflect the distal tip 145 of the 
catheter shaft away from the aortic wall as the catheter is advanced 
through the aortic arch A and into the ascending aorta B. This reduces the 
likelihood of any trauma caused to the aortic wall by the catheterization 
and reduces the chances of dislodging any calcifications or other emboli 
from the aortic wall as the catheter 144 passes. Once the catheter 144 is 
in place in the ascending aorta B and the occlusion balloon 151 is 
inflated, the position of the catheter tip 145 can be verified 
fluoroscopically and the steering mechanism used to direct the tip 145 of 
the catheter toward the center of the aortic lumen in spite of any 
curvature in the ascending aorta B or eccentricities in the occlusion 
balloon 151. If any diagnostic or therapeutic instruments are to be 
delivered through the inner lumen 152 of the endoaortic partitioning 
catheter 144 the steering mechanism can be used for centering the distal 
tip 145 of the catheter 144 with respect to the aortic valve V or for 
directing the instruments to other anatomical features within the heart or 
the aortic root R. The steering mechanism can also be used for directing 
the catheter tip 145 toward the anterior wall or the highest point in the 
ascending aorta for de-airing the heart and the ascending aorta at the 
completion of the interventional procedure before deflating the occlusion 
balloon to reverse the cardioplegic arrest, as described above in relation 
to FIG. 25. 
Another aspect of the present invention is illustrated in FIG. 28. In this 
embodiment, a fiberoptic illumination device 153 has been combined with 
the endoaortic partitioning catheter 154. The fiberoptic illumination 
device 153 can serve two distinct purposes. The first function of the 
fiberoptic illumination device 153 can be for transillumination of the 
aortic wall W for detecting plaque and calcifications P in the aortic wall 
and for identifying the optimal point for creating a proximal anastomosis 
of a coronary bypass vein graft. In this embodiment, a fiberoptic bundle 
155 is extended through the shaft 156 of the endoaortic partitioning 
catheter 154 to the distal end. The fiberoptic bundle 155 may be built 
into the wall of the catheter shaft 156 or a separate fiberoptic bundle 
155 can be removably inserted through the infusion lumen of the catheter 
154. At the distal end of the fiberoptic bundle 155 is a light diffuser 
157 or a means for directing a broad lateral beam of light. The proximal 
end of the fiberoptic bundle is connected to a high intensity source of 
visible light 158. When the light beam or diffuse illumination passes 
through the wall W of the aorta, calcifications and heavy atherosclerotic 
plaque P can be detected as shadows in the aortic wall W. The exterior of 
the aorta can be observed with a thoracoscope inserted through an 
intercostal access port into the patient's chest. The light source for the 
thoracoscope should be turned off while performing the transillumination 
so that the light coming through the aortic wall can be clearly seen. When 
this technique is used in open-chest bypass surgery, the lights in the 
operating room should be dimmed so that the light coming through the 
aortic wall can be seen. A clear, brightly lit section of the aortic wall 
W without shadows will indicate a relatively plaque free area of the aorta 
suitable for making the distal anastomosis. If a separate fiberoptic 
bundle 155 is inserted through the infusion lumen of the catheter 154, it 
can be manipulated from outside of the patient's body to scan the entire 
ascending aorta B to find the optimum anastomosis site or to find multiple 
anastomosis sites for multi-vessel bypass operations. 
The second function of the fiberoptic illumination device 153 can be for 
facilitating placement of the endoaortic partitioning catheter 154 without 
the need for fluoroscopic guidance. In this embodiment, a fiberoptic 
bundle 155 is extended through the shaft 156 of the endoaortic 
partitioning catheter 154 to the distal end. Again, the fiberoptic bundle 
155 may be built into the wall of the catheter shaft 156 or a separate 
fiberoptic bundle 155 can be removably inserted through the infusion lumen 
of the catheter 154. Located at the distal end of the fiberoptic bundle 
155 is a means 157 for directing a narrow lateral beam of light to create 
a spot or a 360.degree. ring of light around the tip of the catheter. The 
proximal end of the fiberoptic bundle 155 is connected to a high intensity 
source of visible light 158. When the endoaortic partitioning catheter 154 
is inserted into the ascending aorta B, the position of the catheter tip 
can be determined by the position of the spot or ring of light where it 
shines through the aortic wall W. When the endoaortic partitioning 
catheter 154 is in the correct position, the occlusion balloon 159 can be 
inflated and a cardioplegic agent infused to arrest the heart. 
These two functions of the fiberoptic illumination device 153 can be 
combined into one device if the optical elements are chosen to deliver a 
beam which is a compromise between the broad beam needed for aortic wall 
transillumination and the narrow beam preferred for the catheter location 
function. Alternatively, an optical system could be chosen which is 
selectively capable of delivering a broad or narrow lateral beam of light. 
In other alternatively embodiments, the occlusion balloon 158 can be 
illuminated from the interior with the fiberoptic illumination device 153 
to monitor balloon placement, inflation and migration. The effectiveness 
of the illumination can be enhanced by incorporating reflective or 
fluorescent material in the balloon or the inflation fluid. 
Being able to detect the precise position of the endoaortic partitioning 
catheter 154 without the need for fluoroscopic imaging has the potential 
of simplifying the catheter placement procedure and the equipment needed 
in the operating room. Other non-fluoroscopic means for detecting the 
position of the catheter tip include placing a metallic or magnetic marker 
at the tip of the catheter and using a thoracoscopically placed Hall 
effect proximity detector or magnetometer in the chest cavity to detect 
the position of the catheter tip through the aortic wall. Another means of 
detecting the position of the catheter tip within the ascending aorta is 
by ultrasonic imaging. An endoscopic ultrasonic imaging probe can be 
introduced through an access port in the chest or a transoesophageal 
ultrasound probe can be used. The imaging of the catheter can be enhanced 
by placing an echogenic marker near the tip of the catheter. A material 
with significantly higher or lower acoustic impedance than the catheter 
and the surrounding tissue and blood can serve as an echogenic marker. For 
example, a metal ring with a roughened exterior surface or an air-filled 
pocket or ring of closed cell foam mounted on or embedded in the tip of 
the catheter will serve as an echogenic marker. The catheter tip can be 
observed with ultrasonic imaging as the catheter is advanced into the 
ascending aorta to assure proper placement of the occlusion balloon. 
Another approach for facilitating placement of the endoaortic partitioning 
catheter without the need for fluoroscopic guidance is illustrated in FIG. 
29. This embodiment of the endoaortic partitioning catheter 160 has a 
second exandable member 161 mounted on the distal end of the catheter 
distal to the first exandable occlusion member 162. In a particular 
embodiment, the distal expandable member 161 is an inflatable balloon 
having a proximal balloon neck 163 which is attached to the catheter shaft 
166 and a distal balloon neck 164 which is inverted and attached to the 
distal tip 165 of the catheter shaft. When the distal expandable member 
161 is inflated, it expands to surround and protect the distal tip 165 of 
the catheter. If an expandable balloon is used for the first exandable 
occlusion member 162 the first 162 and second 161 expandable members can 
be inflated through a single inflation lumen within the catheter shaft 
166. Preferably, however a separate second inflation lumen is provided for 
individually inflating the distal expandable member 162. The distal 
expandable member 162 preferably has a smaller expanded diameter than the 
first exandable occlusion member 161 so that it does not occlude the lumen 
of the ascending aorta B. 
In operation, the endoaortic partitioning catheter 160 is inserted and 
advanced into the descending aorta D. Then, the distal expandable member 
161 is inflated to act as a soft protective bumper for the distal end 165 
of the catheter 160. The catheter 160 can be advanced over the aortic arch 
A and into the ascending aorta B with very little concern about causing 
trauma to the aortic wall or dislodging any calcifications or other emboli 
from the aortic wall as the catheter passes. When the catheter 160 is in 
the ascending aorta B, it is advanced slowly until the distal expandable 
member 161 comes into contact with the aortic valve V. The soft cushion 
provided by the inflated distal expandable member 161 prevents any damage 
to the aortic valve V. The operator will be able to feel that the catheter 
160 has stopped advancing from the proximal end of the catheter which is 
outside of the patient's body and will know that the first exandable 
occlusion member 162 is in proper position in the ascending aorta B 
between the coronary ostia and the brachiocephalic artery without the need 
for fluoroscopic verification. The first exandable occlusion member 162 
can be inflated to occlude the ascending aorta B and a cardioplegic agent 
infused through the perfusion lumen that exits the catheter through a port 
167 distal to the first exandable occlusion member 162. 
FIGS. 30A and 30B are detail drawings of an additional feature of the 
invention which is a frictional locking suture ring 900 for use with the 
endoaortic partitioning catheter. For indwelling catheters, such as the 
endoaortic partitioning catheter, it is often desirable to fasten the 
catheter to the patient or to the surgical drapes to prevent undesired 
migration or dislodgement of the catheter from its correct position. The 
frictional locking suture ring 900 of FIGS. 30A and 30B is provided as 
part of the invention to facilitate anchoring the catheter in place to 
avoid unintentional movement of the catheter after it has been positioned 
in the ascending aorta. Typical suture rings on introducer sheaths, 
central venous catheters and other indwelling catheters are located at a 
fixed position near the proximal hub of the catheter. This is generally 
adequate for catheters where the precise placement of the distal tip of 
the catheter is not critical. With the endoaortic partitioning catheter, 
however, the precise placement of the distal tip of the catheter within 
the ascending aorta is highly critical and the distance from the point of 
insertion of the catheter into the peripheral arterial access site to the 
ascending aorta is highly variable from patient to patient. Therefore, a 
standard, fixed-position suture ring would be wholly inadequate in the 
present application. The frictional locking suture ring of FIGS. 30A and 
30B allows the endoaortic partitioning catheter to be precisely positioned 
and reliably anchored in place with any desired length of the catheter 
shaft inserted at the access site. 
The frictional locking suture ring 900 is preferably made from a tube 902 
of a resilient, high-tack polymer, preferably an extrudable or injection 
moldable thermoplastic elastomer, such as a thermoplastic polyurethane 
with a hardness in the range of 70-90 Shore A durometer or Kraton.TM. 
(Shell Chemical Co.) thermoplastic elastomer with a hardness of about 40 
Shore A durometer. The length of the tube 902 is typically from 2-3 cm. 
The internal diameter of the tube 902 is slightly larger than the external 
diameter of the shaft of the endoaortic partitioning catheter 920. In an 
exemplary embodiment for use with a 4 mm diameter or 12 French catheter, 
the internal diameter of the tube 902 is preferably about 4.5-4.8 mm, 
providing a diametrical clearance of approximately 0.5-0.8 mm. The 
external diameter of the tube 902 is typically about 6.5-7.0 mm. There is 
a longitudinal slot 904 about 1.2-2.0 mm wide through the side of the tube 
902. 
The frictional locking suture ring 900 is placed over the exterior of the 
endoaortic partitioning catheter 920 with the shaft of the catheter 
running through the lumen of the tube. Because of the diametrical 
clearance between the exterior of the catheter 920 and the interior of the 
tube 902, the suture ring 900 is free to move along the length of the 
catheter 920. However, when a suture 906 or other ligature is tied around 
the suture ring 900, the tube 902 compresses around the exterior of the 
catheter 920 and the high friction due to the tackiness of the suture ring 
material creates a firm, nonslip grip on the catheter shaft 920. To 
facilitate securing the suture 906 to the suture ring 900, a 
circumferential groove 908 is provided on the exterior of the tube 902. In 
the illustrative embodiment shown in FIGS. 30A and 30B, there are three 
circumferential grooves 908 around the tube at positions near the proximal 
end, the center and the distal end of the longitudinal slot 904 to provide 
places for tying a suture 906 around the suture ring 900. In an injection 
molded embodiment of the suture ring 900, other suture attachment means, 
such as one or more eyelets, can easily be provided on the exterior of the 
tube 902. 
In order to increase the frictional grip between the frictional locking 
suture ring 900 and the shaft of the endoaortic partitioning catheter 920, 
a strip of high friction material 910 may be provided on the interior of 
the tube 902. In the illustrative embodiment of FIGS. 30A and 30B a 1.0 mm 
wide strip of high friction tape 910 has been adhesively bonded to the 
interior of the tube 902. A suitable material for use in this application 
is a self-adhesive high friction tape available from 3M Manufacturing Co., 
Inc. which is made of a polyurethane film with mineral particles embedded 
in the exterior surface to enhance the frictional properties. The high 
friction tape 910 is mounted in the tube 902 with the high friction 
gripping surface oriented toward the lumen 912 of the tube 902. When a 
suture 906 is tied around the exterior of the frictional locking suture 
ring 900, the high friction surface of the tape 910 is pressed against the 
exterior of the catheter shaft 920 to increase the grip on the catheter. 
Preferably, the frictional locking suture ring 900 is placed over the 
catheter shaft from the distal end during manufacturing. In use, the 
suture ring 900 initially resides in an out of the way position at the 
proximal end of the catheter near the proximal hub while the catheter 920 
is being introduced and maneuvered into position within the patient's 
aorta. Once the distal end of the catheter has been maneuvered to the 
proper position, the catheter 920 can be secured in position by sliding 
the suture ring 900 along the catheter shaft 920 until it is close to the 
introduction site. A suture 906 is tied around exterior of the suture ring 
900 to create a frictional grip between the suture ring 900 and the 
catheter shaft 920. The suture 906 is then stitched through the patient's 
skin close to the insertion site and tied. This securely fastens the 
catheter 920 in the desired position relative to the patient's body with 
the correct length of catheter inserted into the patient's vasculature. If 
preferred, separate sutures can be used for tying the suture ring 900 and 
stitching it to the patient. Alternatively, the suture ring 900 can be 
secured to the surgical drapes covering the patient, though this is less 
preferred because there can be relative movement between the drapes and 
the catheter introduction site that could result in movement of the 
catheter from its desired position. 
If it becomes necessary to reposition the catheter 920 at any time during 
the procedure, the frictional grip can be released by untying or cutting 
the suture 906 around the suture ring 900. The catheter 920 can be 
repositioned by sliding it through the lumen 912 of the suture ring and 
then it can be secured in the new position by retying the suture 906 
around the suture ring 900. When it is time to remove the catheter 920, 
the suture 906 fastening the suture ring 900 to the patient can be cut and 
the suture ring 900 withdrawn with the catheter 920. 
In a further aspect of the invention, illustrated in FIGS. 31-34, the 
endoaortic partitioning catheter 895 is coupled to an arterial bypass 
cannula 850 that is specially adapted to serve as a dual purpose arterial 
bypass cannula and introducer sheath so as to allow the catheter 895 and 
the cannula 850 to be introduced through the same arterial puncture. The 
smaller diameter endoaortic partitioning catheters made possible by the 
embodiments described in relation to FIGS. 5-9, are particularly suitable 
for use in combination with the special arterial bypass cannula 850. The 
arterial bypass cannula 850 is configured for connection to a 
cardiopulmonary bypass system for delivering oxygenated blood to the 
patient's arterial system. The arterial bypass cannula 850, shown in FIG. 
31, has a cannula body 851 which is preferably made of a transparent, 
flexible, biocompatible polyurethane elastomer or similar material. In one 
preferred embodiment, the cannula body 851 has a 45.degree. beveled distal 
end 853, a proximal end 852, a blood flow lumen 857 extending between the 
proximal end 852 and the distal end 853, and an outflow port 891 at the 
distal end 853. Alternatively, the cannula body 851 can have a straight 
cut distal end with chamfered or rounded edge. Optionally, a plurality of 
additional outflow ports may be provided along the length of cannula body 
851, particularly near distal end 853. The cannula body 851 is tapered 
from the proximal end 852 to the distal end 853 and, in one preferred 
embodiment, the tapered cannula body 851 is reinforced with a coil of flat 
stainless steel wire 854 embedded in the wall of the cannula body 851. 
Adjacent to the proximal end 852 of the cannula body 851, proximal to the 
reinforcing coil 851, is a clamp site 851 which is a flexible section of 
the tubular cannula body 851 that can be clamped with an external clamp, 
such as a Vorse type tube occluding clamp, forming a hemostatic seal to 
temporarily stop blood flow through the lumen 857 of the cannula 850. In a 
preferred embodiment, the cannula body 851 has a length between about 10 
cm and 60 cm, and preferably between about 15 cm and 30 cm. In one 
particular embodiment, the cannula body 851 has a distal external diameter 
of approximately 7 mm or 21 French (Charriere scale) and a distal internal 
diameter of approximately 6.0 mm or 18 French. In a second particular 
embodiment, the cannula body 851 has a distal external diameter of 
approximately 7.7 mm or 23 French (Charriere scale) and a distal internal 
diameter of approximately 6.7 mm or 20 French. Preferably, the proximal 
end 852 of the cannula body 851 of either embodiment has an internal 
diameter of approximately 3/8 inch or 9.5 mm. The choice of which 
embodiment of the arterial bypass cannula 850 to use for a given patient 
will depend on the size of the patient and the diameter of the artery 
chosen for the arterial cannulation site. Generally, patients with a 
larger body mass will require a higher infusion rate of oxygenated blood 
while on cardiopulmonary bypass, therefore the larger arterial bypass 
cannula 850 should be chosen if the size of the artery allows. 
An adapter assembly 865 is connected to the proximal end 852 of the cannula 
body 851. In one preferred embodiment, the adapter assembly 865 and the 
cannula body 851 are supplied preassembled as a single, sterile, 
ready-to-use unit. Alternatively, the adapter assembly 865 can be packaged 
and sold as a separate unit to be connected to the cannula body 851 at the 
point of use. The adapter assembly 865 has a Y-fitting 858 which is 
connected to the proximal end 852 of the cannula body 851. The Y-fitting 
858 has a first branch ending in a barbed connector 859 which is 
configured for fluid connection to tubing 892 from a cardiopulmonary 
bypass system, as shown in FIG. 34. To prepare the arterial bypass cannula 
850 for insertion into a peripheral artery, such as a patient's femoral 
artery or brachial artery, by an arterial cutdown or by a percutaneous 
Seldinger technique, a connector plug 871, which is molded of a soft, 
elastomeric material, is placed over the barbed connector 859. A tapered 
dilator 867 is passed through a wiper-type hemostasis seal 872 in the 
connector plug 871. The wiper-type hemostasis seal 872 is a hole through 
the elastomeric connector plug 871 that has a slight interference fit with 
the external diameter of the dilator 867. A series of ridges can be molded 
within the hemostasis seal 872 to reduce the sliding friction on the 
dilator 867 while maintaining a hemostatic seal. The dilator 867 has a 
tapered distal tip 869, a proximal hub 870 with a luer lock connector, and 
a guidewire lumen, sized for an 0.038 inch diameter guidewire, that runs 
from the distal tip 869 to the proximal hub 870. The diameter of the 
dilator 867 is such that the dilator 867 substantially fills the cannula 
lumen 857 at the distal end 853 of the cannula body 851. The length of the 
dilator 867 is such that the distal tip 869 of the dilator 867 extends 
approximately 4 to 5 cm beyond the beveled end 853 of the cannula body 851 
when the dilator hub 870 is against the connector plug 870. The dilator 
867 may assume a bend 873 in it at the point where the dilator 867 passes 
through the Y-fitting 858 when the dilator 867 is fully inserted. One or 
more depth markers 874, 875 can be printed on the dilator 867 with a 
nontoxic, biocompatible ink. One depth marker 874 may be placed so that, 
when the marker 874 is just proximal to the hemostasis seal 872 on the 
elastomeric connector plug 871, the tapered distal tip 869 of the dilator 
867 is just emerging from the beveled end 853 of the cannula body 851. In 
one particular embodiment, the tapered dilator 867 is made of extruded 
polyurethane with a radiopaque filler so that the position of the dilator 
can be verified fluoroscopically. 
A second branch of the Y-fitting 858 is connected to an extension tube 862 
which terminates in a hemostasis valve 876 configured to receive the 
endoaortic partitioning catheter 895 therethrough. The extension tube 862 
has a flexible middle section which serves as a proximal clamp site 864 
that can be clamped with an external damp, such as a Vorse type tube 
occluding clamp, forming a hemostatic seal to temporarily stop blood flow 
through the lumen 863 of the extension tube 862. The lumen 863 of the 
extension tube 862 between the proximal clamp site 864 and the hemostasis 
valve 876 serves as a catheter insertion chamber 866, the function of 
which will be more fully explained in connection with FIG. 33. 
In a preferred embodiment of the arterial bypass cannula 850, the 
hemostasis valve 876 is a type of compression fitting known in the 
industry as a Tuohy-Borst adapter. The Tuohy-Borst adapter 876 is shown in 
greater detail in FIG. 32. The Tuohy-Borst adapter 876 has a compressible 
tubular or ring-shaped elastomeric seal 883 that fits within a counterbore 
879 in the fitting body 877. The elastomeric seal 883 is preferably made 
from a soft, resilient, self-lubricating elastomeric material, such as 
silicone rubber having a hardness of approximately 20-25 Shore A 
durometer. The elastomeric seal 883 has a central passage 884 with a 
beveled entry 885 on the proximal end of the passage 884. The elastomeric 
seal 883 has a beveled distal surface 886 angled at about 45.degree. which 
fits against a tapered seat 880 in the bottom of the counterbore 879 that 
is angled at about 60.degree.. A threaded compression cap 887 screws onto 
the fitting body 877. The threaded cap 887 has a tubular extension 887 
which fits within the counterbore 879 in the fitting body 877. An 
externally threaded section 888 on the proximal end of the tubular 
extension 887 engages an internally threaded section 881 within the 
proximal end of the counterbore 879. When the threaded cap 887 is screwed 
down onto the fitting body 877, the tubular extension 889 bears on the 
elastomeric seal 883 forcing it against the tapered seat 880 of the 
counterbore 879. The resultant force on the elastomeric seal 883 squeezes 
the elastomeric seal 883 inward to close off the passage central 884 to 
make a hemostatic seal. When the threaded cap 887 is unscrewed again from 
the fitting body 877, the central passage 884 of the elastomeric seal 883 
opens up again. The deliberate 15.degree. mismatch between the angle of 
the beveled distal surface 886 of the elastomeric seal 883 and the tapered 
seat 880 of the counterbore 879 prevents the elastomeric seal 883 from 
binding and causes the central passage 884 to open up reliably when the 
threaded cap 887 is unscrewed from the fitting body 887. An internal ridge 
890 within the threaded cap 887 engages in a snap fit with an external 
ridge 882 on the proximal end of the fitting body 877 to keep the threaded 
cap 887 from being inadvertently separated from the fitting body 877 if 
the threaded cap 887 is unscrewed to the point where the threads 888, 881 
are no longer engaged. 
In one particular embodiment, the central passage 884 of the elastomeric 
seal 883 has an internal diameter of about 5 mm to allow clearance for 
inserting a catheter 895 with a shaft diameter of 3-4 mm through the 
Tuohy-Borst adapter 876 without damaging the occlusion balloon 896 mounted 
on it. The Tuohy-Borst adapter 876 is adjustable through a range of 
positions, including a fully open position for inserting the balloon 
catheter 896, a partially dosed position for creating a sliding hemostatic 
seal against the shaft 897 of the catheter 895, and a completely closed 
position for creating a hemostatic seal with no catheter in the central 
passage 884. In an alternative embodiment, the central passage 884 of the 
elastomeric seal 883 can be sized to have a slight interference fit with 
the shaft 897 of the catheter 895 when uncompressed. In this embodiment, 
the Tuohy-Borst adapter 876 has positions which include a fully open 
position for creating a sliding hemostatic seal against the shaft 897 of 
the catheter 895, and a completely closed position for creating a 
hemostatic seal with no catheter in the central passage 884. In a second 
alternative embodiment, a separate ring-like wiper seal (not shown) is 
added in series with the Tuohy-Borst adapter 876 to create a passive 
sliding hemostatic seal against the shaft 897 of the catheter 895 without 
the necessity of tightening the threaded cap 887. Additionally, the 
Tuohy-Borst adapter 876, in either embodiment, may have a tightly closed 
position for securing the catheter shaft 897 with respect to the patient. 
In other alternative embodiments, other known hemostasis valves may be 
substituted for the Tuohy-Borst adapter 876 as just described. 
In a particularly preferred embodiment, the internal surface of the lumen 
863 of the extension tube 862 and/or the internal surface of the lumen 857 
of the cannula body 851 are coated with a highly lubricious biocompatible 
coating, such as polyvinyl pyrrolidone, to ease the passage of the 
endoaortic partitioning catheter 895, and especially the occlusion balloon 
896, through these lumens. Other commercially available lubricious 
biocompatible coatings can also be used, such as Photo-Link.TM. coating 
available from BSI Surface Modification Services of Eden Prairie, Minn; 
sodium hyaluronate coating available from Biocoat of Fort Washington, Pa; 
and proprietary silicone coatings available from TUA of Sarasota, Fla. 
Similarly, a distal portion of the exterior of the cannula body 851 can be 
coated with one of these lubricious biocompatible coatings to facilitate 
insertion of the arterial bypass cannula 850 into the artery at the 
cannulation site. Furthermore, the endoaortic partitioning catheter 895 
itself, in any of the embodiments described herein, can be coated with one 
of these lubricious biocompatible coatings to facilitate its insertion and 
passage through the arterial bypass cannula 850 and the patient's 
vasculature. Preferably, the occlusion balloon 896 of the endoaortic 
partitioning catheter 895 should be free of any lubricious coating so that 
there is sufficient friction between the expanded occlusion balloon and 
the interior aortic wall to prevent accidental dislodgement or migration 
of the occlusion balloon 896. 
In operation, the arterial bypass cannula 850 is prepared for insertion as 
shown in FIG. 31, with the tapered dilator 867 in place in the blood flow 
lumen 857 of the cannula body 851 and with the Tuohy-Borst fitting 876 
completely closed. An arterial cutdown is made into an artery, preferably 
the patient's femoral artery, at the cannulation site or a guidewire is 
placed percutaneously using the Seldinger technique and the dilator 867 
and the distal end 853 of the cannula body 851 are inserted into the lumen 
of the artery with the bevel up. A suture 894 can be tied around the 
artery 893 where the cannula body 851, as shown in FIG. 33, inserts to 
avoid bleeding from the artery 893 at the cannulation site. The dilator 
867 is then withdrawn from the cannula body 851, allowing blood to flash 
back and fill the lumen 857 of the cannula body 851. When the tip 868 of 
the dilator 867 is proximal to the distal clamp site 856 an external clamp 
is applied to the distal clamp site 856 to stop further blood flow. The 
dilator 867 is completely withdrawn and the connector plug 871 is removed 
so that a tube 892 from the cardiopulmonary bypass system can be attached 
to the barbed connector 859 of the Y-fitting 858, as shown in FIG. 33. Air 
is bled from the arterial bypass cannula 850 by elevating the extension 
tube 862 and opening the Tuohy-Borst fitting 876 slightly and releasing 
the external on the distal damp site 856 to allow the blood to flow out 
through the Tuohy-Borst fitting 876. Alternatively, air can be bled out of 
the arterial bypass cannula 850, through an optional vent fitting with a 
luer cap (not shown) that can be provided on the Y-fitting 858. The 
optional vent fitting can be also used as a port for monitoring perfusion 
pressure within the arterial bypass cannula 850. Once the air is bled out 
of the system, the external damp can be removed from the distal clamp site 
856 the cardiopulmonary bypass system pump can be turned on to perfuse the 
patient's arterial system with oxygenated blood at a rate of about 3 to 6 
liters/minute, preferably at a pump pressure of less than about 500 mmHg. 
To introduce the endoaortic partitioning catheter 895 into the arterial 
bypass cannula 850, an external clamp 891 is placed on the proximal clamp 
site 864, as shown in FIG. 33, to stop blood from flowing out through the 
extension tube 862 and the Tuohy-Borst adapter 876 is opened all the way 
by unscrewing the threaded cap 887 to open up the passage 884 through the 
elastomeric seal 883. The distal end of the endoaortic partitioning 
catheter 895 with the occlusion balloon 896 mounted thereon is inserted 
through the passage 884 of the Tuohy-Borst adapter 876 into the insertion 
chamber 866 of the arterial bypass cannula 850. Optionally, first and 
second depth markers 898, 899 may be printed on the shaft 897 of the 
endoaortic partitioning catheter 895 with a nontoxic, biocompatible ink. 
The first depth marker 898 on the catheter 895 indicates when the 
occlusion balloon 896 is entirely distal to the elastomeric seal 883. When 
the first depth marker 898 is positioned just proximal to the threaded cap 
887, the Tuohy-Borst adapter 876 should be tightened to create a sliding, 
hemostatic seal around the catheter shaft 897. Now, the clamp 891 can be 
removed to allow the catheter 895 to be advanced distally through the 
arterial bypass cannula 850. 
Before the endoaortic partitioning catheter 895 enters the blood flow lumen 
857 within the Y-fitting 858, the perfusion rate from the cardiopulmonary 
bypass system pump should be temporarily turned down to a rate of about 1 
to 2 liters/minute to avoid hemolysis, tubing disruptions or other 
complications due to the additional flow resistance caused by the 
occlusion balloon 896 as it passes through the blood flow lumen 857. The 
catheter 895 can now be advanced distally until the occlusion balloon 986 
is distal to the distal end 853 of the cannula body 851. A second depth 
marker 899 on the catheter 895 indicates when the occlusion balloon 896 is 
entirely distal to the distal end 853 of the cannula body 851. When the 
second depth marker 898 reaches the proximal end of the threaded cap 887, 
as shown in FIG. 34, the perfusion rate from the cardiopulmonary bypass 
system pump should be returned to a rate of about 3 to 6 liters/minute. 
The endoaortic partitioning catheter 895 can now be advanced into the 
ascending aorta for partitioning the heart and inducing cardioplegic 
arrest according to the methods described above. When the endoaortic 
partitioning catheter 895 is in position within the ascending aorta the 
Tuohy-Borst adapter 876 can be tightened around the catheter 895 to act as 
a friction lock to hold the catheter in place. 
After completion of the surgical procedure on the heart, the endoaortic 
partitioning catheter 895 can be removed from the arterial bypass cannula 
850 by reversing the sequence of operations described above. The arterial 
bypass cannula 850 can remain in place until the patient has been weaned 
from cardiopulmonary bypass, then the arterial bypass cannula 850 can be 
removed and the arterial puncture site repaired. 
It should be noted that for the venous side of the cardiopulmonary bypass 
system, a similar dual purpose venous bypass cannula and introducer sheath 
with the above-described features can be used for accessing the femoral 
vein and for introducing a venting catheter or other devices into the 
venous side of the circulatory system. In a venous configuration the dual 
purpose venous bypass cannula and introducer sheath preferably has an 
external diameter of about 21 to 32 French units, an internal diameter of 
about 19 to 30 French units, and a length of about 50 to 75 cm. 
FIGS. 35A-35C illustrate another means of steering the distal tip 171 of 
the endoaortic partitioning catheter 170 for centering the catheter tip 
within the ascending aorta B. The endoaortic partitioning catheter 170 is 
shown positioned within the patient's aortic arch A in FIG. 35A. The 
distal tip 171 of the catheter 170 is made steerable by a multichamber 
occlusion balloon 172 mounted on the distal portion 173 of the catheter 
which is shown partially cut away in FIG. 35A. The distal portion 173 of 
the catheter 170 has a distal curve which may be a 
180.degree..+-.45.degree. arc or a 270.degree..+-.45.degree. arc, as 
described in previous embodiments. The multichamber occlusion balloon 172 
has a first chamber 174 and a second chamber 175. The balloon 172 is 
mounted so that the first chamber 174 is oriented toward the outside of 
the distal curve and the second chamber 175 is oriented toward the inside 
of the distal curve. A first inflation lumen 176 in the catheter 170 
connects to the first chamber 174 through a first inflation port 178. A 
second inflation lumen 177 in the catheter 170 connects to the second 
chamber 175 through a second inflation port 179. An infusion lumen 181 
connects with one or more infusion ports 182 at the distal tip 171 of the 
catheter 170. 
As shown in the cross section of the deflated occlusion balloon 172 in FIG. 
35B, a partition wall 180 separates the first 174 and second 175 chambers 
of the balloon 172. The first 174 and second 175 chambers of the balloon 
172 may be differentially inflated through the inflation lumens 176, 177. 
For example, the cross section of FIG. 35C shows the first chamber 174 of 
the multichamber occlusion lumen 172 inflated to a greater degree than the 
second chamber 175. Because the first chamber 174 is oriented toward the 
outside of the distal curve of the catheter 170, the distal tip 171 of the 
catheter 170 is forced toward the inside of the aortic arch A, that is, 
toward the left side of the patient, as in FIG. 35A. Alternatively, the 
second chamber 175 can be inflated to a greater degree than the first 
chamber 174 to force the distal tip 171 of the catheter 170 toward the 
outside of the aortic arch A, that is, toward the right side of the 
patient. Thus, the distal tip 171 of the catheter 170 can be steered to 
center the tip 171 within the lumen of the ascending aorta B under 
fluoroscopic observation by inflating and deflating the individual 
chambers of the multichamber occlusion balloon 172. It should be noted 
that the multichamber occlusion balloon 172 is not limited to only two 
chambers. The multichamber occlusion balloon 172 can be made with three, 
four or more chambers to give the distal tip 171 greater degrees of 
steerability. 
It should be noted that while several aspects of the present invention have 
been illustrated and discussed separately in the foregoing description, 
many of these aspects can be advantageously combined into a single, 
multifunction embodiment. As an illustrative example, FIG. 36 shows a 
multifunction embodiment of the endoaortic partitioning catheter 960 
combining several of the inventive aspects previously discussed. The shaft 
964 of the catheter 960 has a coaxial construction with an inner 961 and 
outer 962 tubular member, similar to the embodiments described in 
connection with FIGS. 5A-5D and 6A-6D. The catheter shaft 964 may be made 
with varying degrees of stiffness along the length of the shaft 964, 
culminating in a soft atraumatic tip 965 which may be highly loaded with a 
radiopaque filler. The catheter shaft 964 may be made with a precurved 
distal portion 966 similar to FIGS. 10A-10B, or with a precurved distal 
portion 966 which is out of plane with the proximal portion of the 
catheter shaft 964, as in FIGS. 11A-11B. An expandable occlusion balloon 
963 is mounted on the distal portion 966 of the catheter shaft 964. The 
occlusion balloon 963 preferably has a low profile deflated state with an 
ellipsoidal shape, similar to that shown in FIG. 6A. In addition, the 
occlusion balloon 963 may have an eccentric or asymmetrical inflated 
profile 963', similar to any of the embodiments discussed in relation to 
FIGS. 14-26, or FIG. 35 which would also provide a steering means for the 
distal tip of the catheter, as would the steering mechanism of FIG. 27. 
The occlusion balloon 963 is mounted with its distal balloon neck 967 
attached to the inner tubular member 961 and its proximal balloon neck 
attached to the outer tubular member 962. The inner tubular member 961 is 
attached at its proximal end to a first hub 971 and the outer tubular 
member 962 is attached at its proximal end to a second 969 hub 971 which 
are axially slidably and/or rotatable with respect to one another, similar 
to the embodiments described in relation to FIGS. 8A-8D and 9A-9B. An 
infusion fitting 977, such as a luer lock, on the first hub 971 is 
connected to an infusion lumen 978 which terminates at the distal end of 
the catheter 960. An inflation fitting 970, preferably a luer lock, on the 
second hub 971 is connected to an inflation lumen 979 defined by an 
annular space between the inner 961 and outer 962 tubular members which 
communicates with the interior of the occlusion balloon 963. 
The second hub 969 may be moved proximal and/or rotated with respect to the 
first hub 971 to minimize the deflated profile of the occlusion balloon 
963. The lower deflated profile of the occlusion balloon 963 facilitates 
easy insertion of the catheter 960 through a dual function arterial 
cannula and introducer sheath 850, similar to that described in relation 
to FIGS. 31-34. When the endoaortic partitioning catheter 960 is combined 
with the dual function arterial cannula and introducer sheath 850, the 
shaft 964 of the catheter 960 should be made with an additional 20-25 cm 
of length for a total shaft length of approximately 100-115 cm. The 
diameter of the catheter shaft 964 should also be minimized as much as 
possible to reduce the amount of cross sectional area the catheter shaft 
964 takes up in the blood flow lumen of the arterial cannula 850. To this 
end, this combined embodiment is made with a distal pressure transducer 
972 and a balloon pressure monitoring transducer 973 mounted on the inner 
tubular member 961, as described in relation to FIGS. 7A-7C. The distal 
pressure transducer 972 and the balloon pressure monitoring transducer 973 
are electrically connected to an electrical connector 974 on the first hub 
971. Also on the first hub 971 is a fiberoptic connector 976 which 
connects to a fiberoptic bundle 975 which terminates with a means for 
directing a lateral beam of light at the distal end of the catheter 960 
for aortic transillumination and/or for facilitating nonfluoroscopic 
placement of the catheter 960. The fiberoptic bundle 975 may also be made 
as a separate unit for insertion through the infusion lumen 978 of the 
catheter 960 to further reduce the catheter shaft diameter while 
maintaining maximum functionality. The diameter of the catheter shaft 964 
can thus be reduced to as small as 8 to 10.5 French (2.7-3.5 mm diameter). 
Additionally the endoaortic partitioning catheter 960 may be combined with 
a frictional locking suture ring 900 for anchoring the catheter 960 in the 
proper position after placement, as described in relation to FIGS. 
30A-30B. 
Thus, it can be seen that the methods and devices described herein provide 
a system for partitioning a patient's heart and coronary arteries from the 
remainder of the arterial system by occluding the ascending aorta between 
the coronary ostia and the brachiocephalic artery, for inducing 
cardioplegic arrest and for maintaining the patient on cardiopulmonary 
bypass entirely through minimally invasive transluminal access. While the 
above is a complete description of the presently preferred embodiments of 
the invention, various alternatives, modifications and equivalents may be 
used. Therefore, the above description should not be taken as limiting the 
scope of the invention, which is defined by the appended claims.