Drug delivery and dilatation-drug delivery catheters in a rapid exchange configuration

Catheters for drug delivery or for both dilatation and drug delivery are provided with a guide wire lumen terminating within the catheter shaft and having an opening through the catheter shaft to enable a guide wire to exit the catheter shaft substantially distal to the proximal end of the catheter. In one embodiment, drug delivery ports are provided between occlusion balloons. In another embodiment, a dilatation balloon is also provided between the occlusion balloons. In another embodiment, a double layered balloon is provided to simultaneously dilatate the stenosis and deliver medication to the site. Alternatively, a balloon can be provided which only delivers medication.

Drug delivery or dilatation-drug delivery catheters with a guide wire lumen 
terminating within the catheter shaft and an opening to enable the guide 
wire to exit the catheter shaft. 
BACKGROUND OF THE INVENTION 
Percutaneous transluminal angioplasty ("PTA") and percutaneous transluminal 
coronary angioplasty ("PTCA"), wherein a dilatation balloon is advanced 
through the vascular system to a stenosis and inflated to open the 
blockage, is now a commonplace procedure. In about one-third of the cases, 
however, the procedure leads to restenosis that can require another 
dilatation procedure. It is estimated that the total cost of restenosis 
requiring an additional dilatation procedure or some other treatment, is 
over 2 billion dollars per year worldwide. 
Various agents that may reduce restenosis can be applied to the dilatation 
site. For example, antithrombolytic agents such as heparin may prevent 
clotting. Antiproliferative agents, such as dexamethasone, can prevent 
smooth muscle cell migration and proliferation. 
Various methods have been proposed to effectively deliver such agents to 
the dilatation site. For example, in U.S. Pat. No. 5,087,244, to Wolinsky, 
a catheter is disclosed having a thin walled flexible balloon with a 
plurality of small holes. After an angioplastic procedure, such a balloon 
can be advanced to the dilatation site and inflated with heparin, or some 
other medication. The medication exits the inflated balloon, which is in 
contact with the arterial wall, through the holes. 
U.S. Pat. Nos. 4,824,436 and 4,636,195, also to Wolinsky, disclose a 
catheter with a drug delivery conduit provided between a pair of occlusion 
balloons. An embodiment is disclosed wherein a dilatation balloon is also 
provided between the occlusion balloons enabling both dilatation and drug 
delivery with the same catheter. 
Another dilatation-drug delivery catheter is disclosed in U.S. Pat. No. 
4,994,033 to Shockey et al. There, a double layered balloon with small 
holes in its outer layer is provided. Medication is introduced between the 
two layers and inflation fluid is introduced into the interior portion of 
the balloon. The pressure of the inflation fluid dilatates the stenosis 
and forces the medication directly into the tissue being dilatated. 
Drug delivery and dilatation-drug delivery catheters are typically advanced 
to the dilatation site along a guide wire, which is received within a 
guide wire lumen that extends through the entire shaft of the catheter. 
Due to frictional forces between the guide wire and the catheter, 
advancing and removing the catheter can be difficult and time consuming. 
In addition, because the entire catheter covers the guide wire, in order to 
insert or replace an over-the-wire catheter, it is necessary that the 
guide wire protrude from the patient's body by a length greater than the 
length of the catheter. Such a guide wire would be about 300 cm. long, and 
the portion extending from the body would be about 230 cm. Otherwise, the 
guide wire cannot be secured and its position proximate a lesion cannot be 
maintained. Instead of such a long guide wire, an exchange wire can be 
connected to the portion of the guide wire extending from the body when 
exchanging catheters. Exchange wires need to be at least 180 cm. long. In 
either case, additional personnel are needed during the procedure to 
handle the long wire. Even with the additional personnel, manipulation of 
the catheters during an exchange can be awkward. The length and expense of 
the procedure are, therefore, unnecessarily increased. 
SUMMARY OF THE INVENTION 
In accordance with one embodiment of the invention, a drug delivery 
catheter is disclosed comprising a catheter shaft having a distal end, at 
least one drug delivery port proximate the distal end and at least one 
drug delivery lumen for providing a drug to the drug delivery port. The 
catheter shaft further comprises a guide wire lumen extending from the 
distal end of the catheter shaft to a terminus within the catheter shaft. 
The terminus is proximal to the drug delivery port and defines an opening 
proximate the terminus for the guide wire to exit the catheter shaft. The 
catheter shaft, therefore, only covers a portion of guide wire extending 
from the body, obviating the need for a long guide wire or exchange wire. 
Occlusion balloons are preferably provided for isolating the site of drug 
delivery. An additional lumen for perfusion is also preferably provided. 
The distal end of the perfusion lumen is preferably tapered. 
In another embodiment of the invention, a catheter comprises a catheter 
shaft having a distal portion and a distal end; means for conveying a drug 
to the exterior of the catheter; means for delivering the drug to the 
means for conveying; and means for receiving a guide wire within the 
distal portion of the catheter shaft. The means for receiving includes a 
means for the guide wire to exit the distal portion of the catheter shaft 
to an exterior of the catheter shaft. 
In another embodiment of the invention, a dilatation-drug delivery catheter 
is disclosed comprising a catheter shaft with a distal portion, a distal 
end and a proximal end. A dilatation balloon is attached to the distal 
portion of the catheter shaft. A first occlusion balloon is attached to 
the catheter shaft at a location distal to the dilatation balloon and a 
second occlusion balloon is attached to the catheter shaft at a location 
proximal to the dilatation balloon. The catheter shaft further comprises 
at least one drug delivery port in the distal portion of the catheter 
shaft, between the dilatation balloon and the occlusion balloons. At least 
one dilatation lumen is provided in fluid communication with the 
dilatation balloon. At least one inflation lumen is provided in fluid 
communication with the occlusion balloons. At least one drug delivery 
lumen is similarly provided in fluid communication with the drug delivery 
port. 
A guide wire lumen is provided in the distal portion of the catheter shaft. 
The guide wire lumen has a first opening to an exterior of the catheter 
shaft at the distal end of the catheter shaft and a second opening to the 
exterior of the catheter shaft in the distal portion of the catheter shaft 
proximal to the second occlusion balloon and substantially distal to the 
proximal end of the catheter shaft. A guide wire can enter the catheter 
shaft through the first opening and exit the catheter shaft through the 
second opening. As above, since the entire catheter shaft does contain the 
guide wire, neither a long guide wire nor an exchange wire is required. 
Furthermore, since dilatation of the stenosis and drug delivery can be 
provided by the same catheter, problems such as relocating the site of the 
stenosis after dilatation, and time delays replacing catheters, are 
avoided. 
In another embodiment of a dilatation-drug delivery catheter in accordance 
with the present invention, a dilatation balloon has an outer and an inner 
layer attached to the distal portion of a catheter shaft. The inner layer 
defines an inner region proximate the catheter shaft and the outer and 
inner layers define an outer region. The outer layer comprises a plurality 
of openings. A first lumen is in fluid communication with the outer region 
and a second lumen is in fluid communication with the inner region. A 
third lumen is provided in the distal portion of the catheter shaft for 
receiving a guide wire. The third lumen has a first opening to an exterior 
of the catheter shaft at the distal end of the catheter shaft and a second 
opening to the exterior of the catheter shaft in the distal portion of the 
catheter shaft, proximal to the dilatation balloon and substantially 
distal to the proximal end of the catheter shaft. The guide wire can enter 
the catheter shaft through the first opening and can exit the catheter 
shaft through the second opening. 
In-another embodiment of the invention, a drug delivery balloon with a 
plurality of ports is attached to the distal portion of a catheter shaft. 
The catheter shaft further comprises at least one drug delivery lumen in 
fluid communication with the drug delivery balloon, and a lumen in the 
distal portion of the catheter shaft for receiving a guide wire. The guide 
wire lumen has a first opening to the exterior of the catheter shaft at 
the distal end of the catheter shaft and a second opening to the exterior 
of the catheter shaft in the distal portion of the catheter shaft, 
proximal to the drug delivery balloon and substantially distal to the 
proximal end of the catheter shaft. Once again, the guide wire can enter 
the catheter shaft through the first opening and exit the catheter shaft 
through the second opening. A lumen for perfusion is also preferably 
provided. The perfusion lumen preferably has a tapered end.

DESCRIPTION OF THE INVENTION 
FIGS. 1-6 illustrate one embodiment of a drug delivery catheter 10 in 
accordance with the present invention. In FIG. 1, the distal portion of 
the catheter 10 is shown enlarged and in cross-section. The catheter 10 
comprises a catheter shaft 12. Two occlusion balloons 22 and 24 are 
preferably attached to the distal portion of the catheter shaft 12. A 
first lumen 14, which extends from the distal end 26 of the catheter shaft 
12 to a terminus 14a proximal the occlusion balloon 24, is provided to 
receive a guide wire 28. An opening 30 is provided in the wall of the 
catheter shaft 12 proximate the terminus. The first lumen 14 is preferably 
located proximate the periphery of the catheter shaft 12. The guide wire 
28 can enter the catheter shaft 12 through an opening 31 in the first 
lumen 14 at the distal end 26 of the catheter shaft 12, and exit through 
the opening 30. The opening 30 is substantially distal of the proximal end 
of the catheter 10. The diameter of the first lumen can be about 0.022 
inches. The distal end of the guide wire 28 extends out of the distal end 
of the lumen 14 during use, as shown in FIG. 1. The distance between the 
distal end of the catheter and the opening 30 is preferably about 5-25 cm. 
The total length of the drug delivery catheter 10 can be from 120-160 cm, 
although longer or shorter lengths are possible. Allowing the guide wire 
28 to exit the catheter shaft 12 through the opening 30 eliminates the 
need for excessively long guide wires or the use of exchange wires, 
because when removed from the body, only a portion of the guide wire 
extending from the body is covered by the catheter 10. There is, 
therefore, sufficient room on the guide wire to hold it in position, as 
the catheter 10 of the invention is inserted or removed from the body. 
With the catheter 10 of the present invention, it is only necessary for 
the guide wire 28 to extend about 75 cm. from the body. 
A second lumen 16 also preferably extends from the distal end 26 of the 
catheter shaft 12 to a terminus 16a proximal to the occlusion balloon 24. 
The diameter of the second lumen can be about 0.013 inches. A plurality of 
ports 32 preferably extends through the wall of the catheter shaft 12 to 
the second lumen 16, enabling the passive perfusion of blood through the 
lumen 16, as discussed further, below. There are preferably between 2-20 
circular or oval ports 32 with a diameter or length, respectively, of 
between about 0.003-0.020 inches. Three perfusion openings 32 are provided 
in this embodiment. Ports 30a can also be provided between the proximal 
occlusion balloon 24 and the opening 30, through to the first lumen 14, to 
enable perfusion of blood through that lumen as well. The distal end 16b 
of the second lumen 16 is preferably tapered, as shown in FIG. 1. This 
makes the opening of the distal end 16b difficult to see, making it 
unlikely that the guide wire 28 will be inserted into the second lumen 16 
instead of the first lumen 14 during use. Alternatively, the lumen 16 can 
extend through the entire length of the catheter shaft 12, enabling active 
perfusion of blood or perfluorochemicals, as is known in the art, and 
discussed further below. 
FIG. 2 is a cross-sectional view of FIG. 1 through line 2--2, showing the 
first and second lumens 14 and 16, and a port 32, as well as third and 
fourth lumens 18 and 20, which are discussed with respect to FIG. 3. 
FIG. 3 is a cross-sectional view of the distal portion of the catheter 10, 
rotated 90.degree.. The guide wire 28 is not shown. In this view, the 
third lumen 18 is shown, which provides inflation fluid to the occlusion 
balloons 22, 24 through ports 34 extending through the catheter shaft 12. 
Preferably, a single lumen 18 is used to inflate both occlusion balloons 
22, 24. The diameter of the third lumen 18 can be about 0.010 inches. 
Separate lumens for each balloon 22, 24 can be provided, as well. 
A fourth lumen 20 for delivering medication is also shown. At least one 
drug delivery port 36 is provided between the occlusion balloons, through 
the catheter shaft 12, to the fourth lumen 20. The diameter of the fourth 
lumen can be about 0.010 inches. There are preferably between 2-20 
circular or oval shaped ports 36 with a diameter or length, respectively, 
of between about 0.003-0.020 inches, to ensure the delivery of adequate 
drug to the dilatation site. Three such ports are shown in FIG. 3. Any 
desired medication can be delivered to the dilatation site, through the 
fourth lumen 20. FIG. 4 is a cross-sectional view of the catheter shaft 12 
through line 4--4 of FIG. 3 showing the orientation of the lumens in that 
view. Additional drug delivery lumens may be provided, as well. 
The occlusion balloon 22, 24, are preferably provided to isolate the 
dilatation site during drug delivery. The occlusion balloons 22, 24 
maintain the drug in proximity with the portion of the arterial wall which 
has been dilatated, improving the absorption and efficacy of the drug. 
FIG. 6 is a plan view of the catheter 10 in the orientation of FIG. 3, 
showing the occlusion balloons 22, 24, inflated as they would be 
immediately prior to and during drug delivery. The opening 30 and the 
exiting guide wire 28, along with the drug delivery ports 36, are also 
shown. The perfusion openings 32 are on the far side of the catheter in 
this view. 
Instead of an integral catheter shaft 12 with multiple lumens, the catheter 
shaft 12 can comprise a plurality of tubes appropriately bonded together. 
In addition, the distal portion of the catheter shaft 12, shown enlarged 
in FIG. 6 can be of a softer material than the remainder of the shaft. The 
softer material of the distal portion eases maneuvering through the 
vascular system while the harder material of the remainder of the shaft 
provides better pushability. The two portions can be simply attached by 
thermal bonding or an adhesive, as is known in the art. Suitable materials 
are discussed below. A stainless steel or tungsten wire (not shown) can 
also be provided in the proximal portion of the catheter shaft 12, to 
further improve the stiffness and pushability of the catheter 10. 
Returning to FIG. 1, the proximal end of the catheter 10 includes two tubes 
72 and 74 which are connected to the catheter shaft 12. One tube is 
connected to the third lumen 18, for the delivery of inflation fluid. The 
other tube is connected to the fourth lumen 20, for the delivery of 
medication. Hubs 78 are connected to each tube. Syringes can be used to 
supply the inflation fluid for the occlusion balloons 22, 24 and any 
desired drug through the tubes 72 and 74. If the catheter 10 is to be 
adapted for active perfusion and the second lumen 16 extends to the 
proximal end of the catheter shaft 12, a third tube (not shown) can be 
attached to the second lumen 16. If additional lumens are provided, 
additional tubes can be attached to the catheter shaft 12 or a Y-adapter 
can be provided. FIG. 5 is a cross-sectional view of the catheter shaft 
along line 5--5 of FIG. 1, showing the third lumen 18 and fourth lumen 20. 
The outer diameter of the catheter 10 and the deflated occlusion balloons 
22, 24 is preferably no greater than about 0.056 inches, so that it can be 
used with a 7 or 8 French guiding catheter. 
To accommodate the tubes 72 and 74 the proximal end of the inner catheter 
shaft 52 flares to an outer diameter of about 0.140 inches at about point 
80. The tubes 72 and 74 are held together by a heat shrink tubing 82. The 
tubes 72, 74 can be connected to the catheter shaft by thermal bonding or 
an adhesive. 
The distal end 26 of the first lumen 14 preferably includes a resilient tip 
96 which comprises a material softer than that of the catheter shaft 12. 
The tip 96 spreads or bends when it contacts body tissue, easing the 
catheter's passage through the vascular system and helping to avoid tissue 
damage. The tip 96 can be made of ultra low density polyethylene 4603 from 
Dow Chemical Corporation, which has a melt flow rate at 190.degree. C. 
(ASTM D-1238) of 0.7-0.9 g/10 min. and a density (ASTM D-792) of 
0.9030-0.9070 g/cc. The tip 96 can also be a nylon or polyamide copolymer, 
such as PEBA 25D from Elf Atochem Deutschland GmbH, which has an ultimate 
tensile strength (ASTM D-638) of 4950 psi minimum ("min."), an ultimate 
elongation (ASTM-638) of 640% min., a flexural modulus (ASTM D-790) of 
2100 psi min., a Durometer (ASTM D-2240) of 25D.+-.4D, and a melting point 
(ASTM D-3418) of 142.degree.-153.degree. C. The tip 96 can be connected to 
the catheter shaft 12 by an adhesive or thermal bonding. 
Radiopaque markers 98 of gold or tantalum, for example, are also preferably 
provided on the catheter shaft 12 within the occlusion balloons 22, 24, as 
shown, to assist in monitoring the position of the catheter on a 
fluoroscope during a PTA or PTCA procedure, as is known in the art. Such 
markers can be provided at other locations, such as proximal to the 
rearmost port 32, as well. 
The catheter shaft 12 and occlusion balloons 22, 24, are preferably coated 
with a lubricous material, such as silicone, acrylimide, or a hydrophilic 
polyurethane coating, to ease passage of the drug delivery catheter 10 of 
the invention through the guiding catheter, as is known in the art. 
The catheter shaft can be of any material suitable for catheters, such as 
linear low density or high density polyethylene, nylon, polyamide, 
polyamide copolymer, polyurethane, polypropylene, polyester copolymer, 
silicone rubber, or other non-thrombogenic materials. Metallic tubing, 
such as stainless steel or Nitinol, a nickel-titanium alloy available from 
Raychem Corporation, for example, can also be used. 
An appropriate linear low density polyethylene is Dowlex 2038 from Dow 
Chemical Company, which has a melt flow rate at 190.degree. C. (ASTM 
D-1238) of 0.85-1.15 g/10 min. and a density (ASTM D792) of 0.9330-0.9370 
g/cc. A high density polyethylene which can be used is LB 8320-00 from 
Quantum Chemical Corporation, which has a melt flow rate at 190.degree. C. 
(ASTM D-1238) of 0.20-0.36 g/10 min. and a density (D-1505) of 0.9566 g/cc 
min. 
A nylon which can be used is nylon 12, such as L2101F Vestamed from Huls 
America Inc., which has a relative viscosity (ISO 307) of 2.05-2.22 and a 
water content (ASTM D-4019) of 0.10 maximum. Another nylon which can be 
used is PEBA 70D from Elf Atochem, which has an ultimate tensile strength 
(ASTM D-638) of 8300 psi min., an ultimate elongation (ASTM D-638) of 400% 
min., a flexural modulus (ASTM D-790) of 67,000 psi min., a Durometer 
(D-2240) of 69D.+-.4D and a melting point (ASTM D-3418) of 
160.degree.-180.degree. C. 
A high density polyethylene which can be used is LM6007 from Quantum 
Chemical Corporation, which has the following characteristics: 
______________________________________ 
Ultimate Tensile Strength 
4400 psi min. 
(ASTM D-638) 
Ultimate Elongation % 600% min. 
at break (ASTM D-638) 
Durometer D Scale 68 .+-. 4.5 
(ASTM D-2240) 
Melt Flow Rate 0.070 (REF) 
at 240.degree. C. 2160 g 
(ASTM D-1238) 
Flexural Modulus at 220,000 psi min. 
Room Temperature 
(ASTM D-790, Procedure B) 
Vicat Softening Point .degree.C. 
125.degree. C. (REF) 
(ASTM D-1525) 
______________________________________ 
If it is desired that the distal portion of the catheter shaft 12 be softer 
than the remainder of the shaft, one appropriate nylon that can be used is 
PEBA 63D from Elf Atochem, which has an ultimate tensile strength (ASTM 
D-638) of 8100 psi min., an ultimate elongation (ASTM D-638) of 300% min., 
a flexural modulus (ASTM D-790) of 49,000 psi min., a durameter (ASTM 
D-2240) of 63D.+-.4D and a melting point (ASTM D-3418) of 
160.degree.-180.degree. C. 
The catheter shaft 12 with the desired number of lumens can be made by 
conventional extrusion processes. To form the flared portion of the 
catheter shaft 12, a bump extrusion process can be used, as is known in 
the art. Instead of an integral catheter shaft 12 with lumens, separate 
tubes can be provided and bonded together, as well. 
The resilient tip 96 can be attached to the catheter shaft by placing a 
small tube of the tip material over the distal end of the catheter shaft 
12 and thermally bonding it into place. An adhesive can be used, as well. 
The tube material can increase the outer diameter of the catheter shaft 
12. To maintain the outer diameter of the catheter shaft 12 less than 
about 0.056 inches after placement of the tube of tip material, the distal 
portion of the catheter shaft can be reduced or "necked-down" an 
appropriate amount prior to attachment of the tip material. To maintain 
the lumens 14 and 16 open while the resilient tip is attached by thermal 
bonding, mandrels are inserted into each lumen. The tube of tip material 
can extend to the region of the catheter shaft 12 where the distal 
occlusion balloon 22 is attached. All or a portion of that balloon would 
then be attached to the tip material. 
During thermal bonding of the tip material, the distal portion of the third 
and fourth lumens 18, 20 close. If it is necessary to close a greater 
portion of either lumen, a small, solid tube of the same material as the 
catheter shaft 12 is inserted into the proximal end of that lumen and 
thermally bonded into place. Adhesive may be used as well. The outer 
diameter of the tube is preferably slightly greater than the diameter of 
that lumen. The mandrels are maintained in the other lumens to keep them 
open. If the third lumen 18 does not close during attachment of the 
resilient tip 96, it can be closed in the same way as the fourth lumen. 
The proximal portions of the first and second lumen 14, 16, can be 
similarly sealed. 
The occlusion balloons 22, 24 can be nylon, polyamide, polyamide copolymer, 
polyethylene, polyethylene terephthalate, polyester elastomers, 
polyurethane, Kraton, silicone, latex or any other soft, non-thrombogenic 
material which will seal against, but not expand, the arterial wall when 
inflated. The balloons can be tubes which expand on inflation or blow 
molded balloons. If the balloon material is compatible with the catheter 
shaft 12, the occlusion balloons 22, 24 can be attached by thermal bonding 
techniques, including laser bonding. An apparatus and process for laser 
bonding balloons onto catheters is disclosed in U.S. Pat. No. 5,267,959, 
which is incorporated by reference herein. An adhesive may be used, as 
well. A nylon which can be used for the occlusion balloons 22, 24 is L25 G 
Grilamid from EMS-Chemie AG, which has a melting point of 178.degree. C., 
a density (DIN 53479) of 1.01 Kg/dm.sup.3, a tensile strength (DIN 53455) 
of 40 N/mm.sup.2, an elongation at yield (DIN 53455) of 10% and a Shore D 
hardness (DIN 53505) of 72. 
The drug delivery catheter of the first embodiment of the present invention 
can be used to deliver medication to the site of the PTA or PTCA procedure 
after dilatation is performed in an ordinary manner. The dilatation 
catheter, which is preferably of a rapid exchange format as described in 
U.S. Pat. No. 4,762,129 to Bonzel, for example, which is incorporated by 
reference herein, is first removed. The drug delivery catheter 10 of the 
present invention can then be introduced into the vascular system and 
advanced to the dilatation site through a guiding catheter, along the same 
guide wire along which the dilatation catheter was advanced to the 
stenosis. No exchange wire is necessary and the guide wire needs to extend 
only about 75 cm. from the body. The distal end of the first lumen 14 of 
the catheter 10 is inserted into the guide wire, such as the guide wire 28 
in FIG. 1. As the catheter 10 is advanced along the guide wire, the guide 
wire exits the catheter 10 from the opening 30. The catheter 10 continues 
to track along the portion of the guide wire within the first lumen 14 as 
it is advanced to the dilatation site. 
The progress of the catheter 10 is followed on a fluoroscope. When the 
dilatation site is reached, the occlusion balloons 22, 24 are inflated 
though the third lumen 18 until the occlusion balloons 22, 24 meet and 
seal against the arterial wall. If perfusion openings 32 and 30a are 
present, blood will then flow through the second lumen 16 and first lumen 
14, respectively, out the distal end of the catheter 10. If the catheter 
10 is configured to allow active perfusion (i.e., if the second lumen 16 
extends the full length of the catheter shaft 12), blood or 
perfluorochemicals such as Fluosol.RTM. can be injected with a syringe 
through tube 76, as is known in the art. 
Antithrombolytic, antiproliferative, or any other type of drug, can now be 
injected through tube 72, the fourth lumen 20 and drug delivery ports 36, 
via a syringe, to the dilatation site. One drug formulation which may be 
promising is dexamethasone absorbed in poly-lactic/poly-glycolic particles 
with diameters substantially less than 100 microns. Such particles can 
adhere to or penetrate the arterial wall. The surface of the particles can 
be treated with cell adhesion proteins and peptides based peptides to 
improve the adhesion of the particles with the arterial wall. An arginine 
glycine aspartic acid based peptide which can be used is Peptite 2000.RTM. 
from Telios Pharmaceuticals, INC. 
After the drug has been applied at the desired pressure and for the desired 
length of time (typically from about 20 seconds to 3 minutes), the 
occlusion balloons are deflated and the drug delivery catheter 10 is 
quickly and easily withdrawn from the blood vessel. 
FIG. 7 is a partial cross-sectional, partial plan view of a second 
embodiment of the present invention, wherein the catheter 100 provides 
both dilatation and drug delivery. The catheter 100 comprises a catheter 
shaft 110 including a first lumen 112, a second lumen 114, a third lumen 
116 and a fourth lumen 118. A dilatation balloon 120 and two occlusion 
balloons 122, 124 are attached to the catheter shaft 110. The dilatation 
balloon 120 is in fluid communication with the first lumen 112 through an 
opening 126. The occlusion balloons are similarly in fluid communication 
with the fourth lumen 118 through openings 128. A port 130 is provided 
through the wall of the catheter shaft 110 to the second lumen 114, 
through which medication can be provided to the dilatation site. As above, 
additional drug delivery lumens can be provided. Additional lumens can be 
provided to deliver fluid to the dilatation balloon 120 or occlusion 
balloons 122, 124, as well. An opening 132 is also provided through the 
wall of the catheter shaft 110 to the third lumen 116. The third lumen, 
which extends through an opening 133 in the distal end 134 of the catheter 
100, receives the guide wire 136, which exits the lumen 116 through the 
opening 132. An additional lumen (not shown) may also be provided for 
active or passive perfusion. The distal end of such a perfusion lumen 
would be preferably tapered, as discussed above. A lubricous coating, as 
discussed above, is also provided on the dilatation balloon 120, as well 
as the remainder of the catheter 100. As above, instead of an integral 
catheter shaft with multiple lumens, the catheter shaft 110 can comprise a 
plurality of tubes appropriately bonded together. 
The dilatation balloon 120 can be of any type and size appropriate for PTA 
and PTCA procedures. For example, the balloon 120 can be of polyethylene, 
polyethylene terephthalate, nylon, polyamide, polyamide copolymer, 
polyurethane, or any other material suitable for a dilatation balloon. The 
balloon 120 can be compliant, non-compliant, or semi-compliant. The 
dilatation balloon 120 can be attached to the catheter shaft 110 through 
thermal bonding, including laser bonding or ultrasonic bonding, or with an 
adhesive, as is known in the art. The balloon 120 is preferably of the 
same or compatible material as the catheter shaft 110, to enable thermal 
bonding. 
A low density polyethylene which can be used for the dilatation balloon 120 
is P.E. 1031 from Rexene Corporation, which has a melt flow rate at 
190.degree..+-.0.2.degree. C. (ASTM D-1238) of 0.4-1.4 g/10 min., a 
density (ASTM D-1505) of 0.93.+-.0.02 g/cc and a melt point (ASTM D-3417, 
D-3418) of 104.degree.-140.degree. C. A linear low density polyethylene 
which can be used is Dowlex 2247A LLPDE from Dow Chemical Corporation, 
which has a melt index at 190.degree. C./2.16 kg (ASTM D-1238) of 2.0-2.6 
g/10 min., a density (ASTM D-1505) of 0.9150-0.9190 g/cc, and a melt point 
(D-3417, D-3418 (REF)) of 122.degree.-125.degree. C. 
The materials discussed above with respect to the first embodiment are 
appropriate for other corresponding components of this embodiment. As in 
the first embodiment, radiopaque markers 138 are provided on the catheter 
shaft 110 beneath the dilatation balloon 120, as well as the occlusion 
balloons 122, 124. The proximal end of the catheter 100 can he essentially 
the same as the proximal end of the catheter 10 in FIG. 1, except that a 
third tube would he attached to the proximal end of the catheter shaft 
110, for supplying dilatation fluid to the dilatation balloon 120, through 
the first lumen 112. A Y-adapter may he used as well, as is known in the 
art. 
In use, the catheter 100 of this embodiment would he inserted onto a guide 
wire, such as the guide wire 136, which has been advanced through a 
guiding catheter to the site of a stenosis, as is known in the art. The 
guide wire can enter the catheter 100 through the opening 133 and exit the 
third lumen 116 through the opening 132. As above, since only a portion of 
the catheter 100 is in frictional engagement with the guide wire, the 
catheter can be easily and quickly advanced to the stenosis and a short 
guide wire can be used. When properly positioned, the dilatation balloon 
120 can be inflated to open the stenosis in a conventional manner. The 
dilatation balloon 120 can then be deflated and the occlusion balloons 
122, 124 can be inflated, as discussed above. Any desired medication can 
then be delivered through the second lumen 114. By enabling both 
dilatation and drug delivery by the same catheter, this embodiment lessens 
the length of the procedure by eliminating the time required to remove a 
dilatation catheter and insert a separate drug delivery catheter. In 
addition, it alleviates the problem of precisely relocating the dilatation 
site for proper positioning of the drug delivery catheter. 
In a third embodiment of the present invention, the catheter 200 can both 
dilatate a stenosis and deliver drug to the dilatation site, through the 
same dilatation balloon. FIG. 8 shows a partial cross-sectional, partial 
plan view of the distal portion of such a catheter 200, with the 
dilatation balloon expanded. The catheter comprises a catheter shaft 210, 
a first lumen 212, a second lumen 214 and a third lumen 216. The second 
lumen 214 receives the guide wire 218 through an opening 219. An opening 
217 is provided though the catheter shaft 210 to the second lumen 214, to 
provide an exit for the guide wire 218. Instead of an integral catheter 
shaft with multiple lumens, the catheter shaft 210 can comprise a 
plurality of the tubes appropriately bonded together, as well. 
The balloon portion of the catheter 200 comprises an outer balloon 220 and 
an inner balloon 230. The second lumen 214 extends through the interior of 
the inner balloon 230. The distal end of the outer balloon 220 is 
thermally or adhesively bonded to the distal end of the inner balloon 230, 
which in turn is thermally or adhesively bonded to the exterior surface of 
the second lumen 214, at 240. 
The proximal ends of the outer balloon 220 and inner balloon 230 are 
thermally or adhesively bonded to the catheter shaft 210 such that the 
region between the outer and inner balloons is in fluid communication with 
the first lumen 212, while the interior of the inner balloon 230 is in 
fluid communication with the third lumen 216. Inflation fluid is provided 
through the third lumen 216 and medication is provided through the first 
lumen 212. A plurality of micropores 280 is formed through the wall of the 
outer balloon 220 for the medication to exit the balloon. Such pores can 
be between 0.01 microns-0.1 mm. Where the outer layer 280 of the balloon 
220 comprises a biaxially oriented plastic material such as polyethylene 
terephthalate or nylon or polyester elastomer, the micropores 28 may be 
formed using a precision laser. 
In use, the guide wire 218 would conventionally be routed through a guide 
catheter and across the lesion to be treated. The distal end 260 of the 
second lumen 214 is fitted over the proximal end of the guide wire 218. As 
in the embodiments above, the guide wire exits the catheter 200 through 
the opening 217. The catheter 200 continues to advance along the portion 
of the guide wire within the second lumen 214, until the balloon portion 
is juxtaposed with the lesion to be treated. While in FIG. 8 the inner and 
outer layers 230, 220 of the balloon are shown in their inflated 
configuration, those layers would tightly conform to the exterior of the 
lumen 214 while being advanced to the stenosis. 
Once the distal end of the catheter 200 is appropriately positioned with 
the aid of a radiopaque marker band 242, the selected medication is 
introduced through the first lumen 212 and into the region between the 
outer balloon 220 and inner balloon 230. The injection of the drug will 
cause some enlargement of the outer balloon 220 but typically the pressure 
at which the drug material is injected is below the point where 
substantial amounts of the drug are ejected out through the micropores 28. 
To perform the simultaneous medication delivery and dilatation, an 
inflation fluid is next injected through the third lumen 216 into the 
interior of the inner balloon 230. As the pressure is increased, typically 
approaching seven to ten atmospheres, the inner layer 230 of the balloon 
inflates to its predetermined maximum diameter and, in doing so, forces 
the drug through the ports 280 to effectively spray the lesion being 
treated with the particular drug. The expansion of the inner balloon 230 
also results in pressure being exerted against the lesion, forcing it 
against the vessel wall as the drug is delivered. 
The use of a balloon to deliver drugs to a dilatation site by a drug 
delivery catheter in accordance with the present invention, is shown in 
the fourth embodiment of FIG. 9. The catheter 300 comprises a drug 
delivery balloon 312, which is thermally or adhesively attached to a 
catheter shaft 310, as described above. In FIG. 9, the balloon 312 is 
shown in an inflated position. A plurality of drug delivery ports 314 are 
provided throughout the balloon 312. The balloon 312 is in fluid 
communication with a drug delivery lumen 316, through a port 318 through 
the wall of the catheter shaft 310. Additional drug delivery lumens may be 
provided, as well. A guide wire lumen 320 is provided in the distal 
portion of the catheter shaft 310, extending from a distal end 322. The 
guide wire lumen 320 terminates in the distal portion of the catheter 
shaft 310, proximal to the drug delivery balloon 312. An opening 324 is 
provided in the wall of the catheter shaft 310, through to the guide wire 
lumen 320. A guide wire 326 can be inserted through an opening 328 in the 
distal end 322 of the catheter shaft 310, and exit through the opening 
324. 
A perfusion lumen 330, with a tapered end 330a, is also preferably 
provided. This lumen can extend through the entire length of the catheter 
shaft 310 enabling active perfusion, as discussed above. Alternatively, it 
can terminate proximal to the drug delivery balloon 312. Openings (not 
shown) would then be provided through the wall of the catheter shaft 310, 
as in the first embodiment, to enable passive perfusion. Instead of an 
integral catheter shaft with lumens, the catheter shaft 310 can comprise a 
plurality of tubes appropriately bonded together, as well. 
The drug delivery and dilatation-drug delivery catheters of the present 
invention enable quick and easy advance and withdrawal of the catheters, 
shortening the time required for the procedure. It also eliminates 
required personnel and equipment, decreasing the cost of the procedure. 
While preferred embodiments of the present invention are described above, 
they are not meant to limit the scope of the invention, which is defined 
by the following claims.