Catheter-based tissue remodeling devices and methods

Devices and methods utilizing a catheter to remodel soft tissue of a patient and, in a preferred embodiment, to reduce the volume of the left ventricle of a heart. In one embodiment, one or more sutures are passed through a wall of the ventricle. The ends of the one suture and, more preferably, the multiples sutures are drawn together to draw tissue portions towards one another. In another embodiment, tissue remodeling clip is implanted into a wall of the ventricle. Ends of the clip are resiliently biased to move relative to one another to draw tissue portions towards one another. In yet another embodiment, a tissue remodeling anchor includes a base and a plurality of legs attached to the base. The legs of the tissue anchor are implanted into a wall of the ventricle and moved toward one another to draw tissue portions toward one another. A retaining member is positioned on the tissue anchor to prevent the legs from moving apart.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to methods for remodeling soft tissue of a patient and, preferably, for remodeling the left ventricle of a patient's heart. The present invention also relates to systems for accomplishing the preferred methods.

2. Description of the Related Art

Congestive heart failure is a description given to a myriad of symptoms that may be the result of the heart's inability to meet the body's demand for blood flow. Heart failure may be considered as the condition in which an abnormality of cardiac function is responsible for the inability of the heart to pump blood at a rate commensurate with the requirements of the metabolizing tissues, or can do so only at an abnormally elevated filling pressure. There are many specific disease processes that can lead to heart failure. Typically, these processes result in dilation of the left ventricular chamber.

The process of ventricular dilation may be the result of chronic volume overload or may result from a specific damage to the myocardium. In a normal heart that is exposed to long-term increased cardiac output requirements, for example, that of an athlete, there is an adaptive process of slight ventricular dilation and muscle hypertrophy. In this way, the heart compensates for the increased cardiac output requirements. With damage to the myocardium, or chronic overload, however, there are increased requirements put on the contracting myocardium to such a level that this compensated state is never achieved and the heart continues to dilate.

One condition that is likely to reduce the blood pumping efficiency of the heart muscle is ventricular dilation. As the chamber becomes enlarged, the internal surface area of the chamber increases rapidly. Blood flowing within the heart applies pressure to the internal surface of the heart chamber and because the blood applies pressure inside the heart chamber across an increased surface area, the force which must be produced by the heart in order to pump blood also increases. In many cases, the cardiac disease responsible for the ventricular dilation also limits the ability of the heart muscle to produce the increased force required to efficiently pump blood, which further compounds the problem.

In many cases, the dilation of the heart chamber becomes progressively worse and the blood pumping efficiency of the heart muscle progressively declines. As this situation worsens, the location area of compromised myocardium may bulge out as the heart contracts, further decreasing the heart's ability to move blood forward. When local wall motion moves in this way it is said to be dyskinetic. The dyskinetic portion of the myocardium may stretch and eventually form an aneurismic bulge.

There is no cure for heart failure, but it can be treated. The primary goals of treatment are to relieve symptoms and prevent worsening of the condition. Symptoms may be relieved by removing excess fluid from the body, improving blood flow and increasing delivery of oxygen to the body tissues. Medical treatment usually comprises lifestyle changes and medications. For example, diuretics have been used to reduce extra cellular fluid which accumulates in congestive heart failure patients, thereby increasing the preloaded condition of the heart. Nitrates, arteriolar vasodilators and angiotensin converting enzyme (ACE) inhibitors have been used to treat heart failure through the reduction of cardiac workload by reducing afterload. Inotropes function to increase cardiac output by increasing the force and speed of cardiac muscle contraction. These drug therapies offer some beneficial effects, but do not stop the progression of the disease.

With respect to the situation of a dilated left ventricle or aneurism bulge, a variety of surgical studies have demonstrated some clinical success of ventricular remodeling and treatment of the dilation of the infarcted ventricle. One such remodeling procedure is referred to as the Batista Procedure. In the Batista Procedure, a small portion of the enlarged lower left ventricle chamber of the heart is removed to reduce the size of the left ventricle towards normal. Typically, the Batista procedure involves the surgeon locating the left anterior descending coronary artery and making two small cuts down and outward to remove a wedge of the left ventricle. The remaining edges of the left ventricle are sewn together, returning the chamber to near its normal size. The incision is closed and the surgery is completed.

A variation of the Batista Procedure, referred to as the Dor Procedure, involves a lengthwise incision in the left ventricle along an area damaged by a myocardial infarction. The undamaged areas of the ventricle are sutured back together, eliminating the affected area. If the damaged area is too large, a patch may be used to cover the damaged area. However, in each of the Batista and Dor procedures, restoration of normal ventricular shape is a complex surgical procedure and very invasive for the patient. Furthermore, these procedures are not applicable to those patients that are not candidates for such invasive surgery.

SUMMARY OF THE INVENTION

Preferred methods of the present invention permit remodeling, tissue joining or tying of the left ventricle using a catheter-based percutaneous approach, which is far less traumatic to the patient than the Batista and Dor procedures. In addition, the methods and preferred devices disclosed herein may be adapted for use in remodeling soft tissue of a patient other than the left ventricle.

A preferred method of remodeling a ventricle of a heart includes introducing a distal portion of at least one catheter through the aorta into the ventricle. The method also includes utilizing the at least one catheter to urge tissue portions on a same side of the ventricle towards each other and to secure the tissue portions such that the volume of the ventricle is reduced.

Another preferred method of decreasing the volume of a ventricle of a heart includes providing an implant in contact with a wall of the ventricle at a contact location internal to the exterior surface of the heart and urging adjacent tissue portions located on a same side of the ventricle towards each other by applying force to the wall with the implant at the internal contact location.

Still another preferred method of reducing the volume of a ventricle of a heart includes gathering tissue by folding a pair of adjacent tissue portions of a wall of the ventricle and repeating the folding to provide a plurality of tissue folds. The gathering comprises securing the plurality of tissue folds to retain the folded portions in close proximity by advancing at least one implant through the interior of the ventricle and securing the implant to a wall of the ventricle.

A preferred embodiment is a cardiac treatment apparatus including a catheter having a catheter body configured to be introduced into a heart chamber through vasculature. The catheter includes a suture passage and a suture passing through the passage. The suture has an end portion. A tissue penetration member is movably mounted within the catheter body such that the penetration member enters an interior surface of a wall of the heart at a first location and exits the interior surface at a second location spaced from the first location. The penetration member is adapted to deliver the suture through the tissue between the locations, whereby application of tension to end portions of the suture draws the tissue locations towards each other.

Another preferred embodiment is a cardiac treatment apparatus including a catheter having a catheter body configured to be introduced into a heart chamber through vasculature. The catheter includes a clip having end portions. The clip is movably mounted in the catheter body such that one end portion enters an interior surface of a wall of the heart to introduce at least a substantial portion of the clip into the wall. An intermediate portion of the clip is embedded in the wall and the end portions are resiliently biased to move relative to each other such that the movement of the end portions draws tissue portions towards each other.

Yet another preferred embodiment is a cardiac treatment apparatus including a catheter having a catheter body configured to be introduced into a heart chamber through vasculature. The catheter includes a tissue anchor having a plurality of legs attached to a base. The legs are configured to pass through an interior surface of a wall of the heart and anchor the legs of the tissue anchor to the wall. The anchored legs have a first position upon the anchoring and are subsequently movable to a second position. The movement of the legs to the second position draws portions of tissue towards each other. The catheter also includes a retaining member for retaining the anchored legs in the second position when the catheter body is removed from the heart.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Preferred embodiments and methods of the present tissue remodeling system permit remodeling, tissue joining, or tying of soft tissue and, in certain preferred arrangements, permit a remodeling of the left ventricle of a heart to reduce the volume of the ventricle. Preferably, the preferred embodiments permit soft tissue remodeling while avoiding the disadvantages of more invasive procedures and the complications that may occur as a result of such procedures. The preferred embodiments and methods may also permit tissue remodeling in patients that are otherwise unable to undergo conventional surgical procedures, such as open heart surgery. Preferred embodiments of the present system permit the duplication of the results of surgical procedures in reducing the volume of the left ventricle by a percutaneous transvascular technique using catheter-based devices. In addition, the preferred embodiments and method disclosed herein may be modified or adapted for use in the remodeling of soft tissue other than the left ventricle of a patient's heart.

FIGS. 1-8illustrate a first preferred embodiment of a tissue remodeling system, generally referred to by the reference numeral50. The illustrated system50includes a catheter assembly52, which preferably includes multiple catheters, or catheter bodies. For simplicity, both the catheter assembly52and individual catheter bodies may be referred to by the term “catheter.” Preferably, the catheter52is sized, shaped and otherwise configured to be movable within a patient's vasculature to a desired remodeling site from a desired insertion site, such as the femoral artery, for example.

Thus, the catheter52may be constructed from a variety of suitable materials using a variety of suitable fabrication techniques, such as those commonly known and used in constructing catheters for medical use. For example, the catheter52, and other catheters discussed herein, may be constructed from polyethylene, polyurethane, silicone or polytetraflouroethylene, or other suitable materials by any suitable process. The illustrated catheter52includes a pair of coaxial catheter bodies. The outer catheter body54is referred to as a guide catheter, or access catheter, herein. The illustrated access catheter54may have an outer diameter of about26F (French) and an inner (lumen) diameter of about22F. However, other suitable dimensions may be selected to suit an individual application of the catheter54.

The inner catheter56is movable within the access catheter54and is referred to as a tissue-penetrating catheter herein. The inner catheter56, in the illustrated arrangement, preferably has an outer diameter of about18F and an inner (lumen) diameter of about13F. However, other dimensions may be selected to suit a desired application of the catheter56.

In the illustrated arrangement, the access catheter54is configured to be steerable to permit the access catheter54to be guided through vasculature to a desired site. Preferably, an anchoring ring58is embedded within a distal end54aof the access catheter54. A deflection wire60preferably is connected to and extends from the anchor ring58within a wall of the catheter54to a proximal end of the catheter54where it is connected to a control knob62. Thus, the control knob62permits a user to selectively move the deflection wire60relative to the catheter54to deflect a distal end54aof the access catheter54. Deflection of the distal end54aof the access catheter54assists a user to routing the catheter54through the vasculature of a patient in a desired path. Alternatively, other suitable steering arrangements or positioning methods of the access catheter54may be employed. In one arrangement, the access catheter54may be configured to slide over a previously placed guidewire (not shown).

Preferably, the distal end54aof the access catheter54is configured to be atraumatic to the patient and, in particular, to the tissue at or near the remodeling site. In the illustrated arrangement, the distal tip54aof the access catheter54carries an inflatable, annular balloon64. Preferably, the balloon64is normally carried by the access catheter54in an uninflated condition so as not to interfere with the passage of the catheter54through a patient's vasculature. Once in place within the left ventricle, the balloon64may be inflated to contact the ventricle wall, help stabilize the distal end of the access catheter54and inhibit a distal tip54aof the access catheter54from damaging tissue. Preferably, the balloon64, in an inflated condition, extends beyond an end surface of the distal end54ato inhibit the distal end surface from contacting the wall of the heart. The balloon64may be constructed from a suitable, material and mounted to the access catheter54by any suitable technique.

An inflation passage66is defined within a wall of the access catheter54and communicates with an interior space of the balloon64. A proximal end of the inflation passage66extends from a proximal end54bof the access catheter54, preferably on a handle defined by the proximal end54band near the steering knob62. Thus, the inflation passage66may be connected to a suitable fluid supply source68, which is configured to supply a pressurized fluid to the balloon64through the inflation passage66. In the illustrated arrangement, the source of fluid68is a standard syringe that is connected to the inflation passage66preferably by suitable plastic tubing70. Any type of suitable connector, such as a luer lock for example, may be used to interconnect the tubing70with the access catheter54and the source of fluid68. If desired, a pressure indicator72may be provided within the system to provide an indication of the fluid pressure within the balloon.

As described above, the tissue-penetrating catheter56is movable within the access catheter54. Preferably, the tissue-penetrating catheter56is movable to a stowed position within the access catheter54wherein, preferably, the entire distal end56aof the tissue-penetrating catheter56is positioned within the distal end54aof the access catheter54. Preferably, the tissue-penetrating catheter56is also movable to a protruding position relative to the access catheter54wherein the distal end56aof the tissue-penetrating catheter56is exposed from the distal end54aof the access catheter54. Preferably, a proximal end56bof the tissue-penetrating catheter56defines a handle configured to permit a user to move the tissue-penetrating catheter56between its stowed and protruding positions.

In the illustrated arrangement, the distal end56aof the tissue-penetrating catheter56is configured to create a passage within soft tissue of a patient and deliver an implant, or a tissue remodeling clip74, into the passage. With reference toFIGS. 1 and 4, preferably the tissue-penetrating catheter56carries the tissue remodeling clip74within its distal end56a. In the illustrated arrangement, a push rod76is positioned within the tissue-penetrating catheter56and proximal of the clip74. The distal end76bof the push rod76preferably defines a contact surface configured to permit the push rod76to apply a force to the clip74. A proximal end76bof the push rod76terminates in a handle, which permits a user of the system50to deploy the clip74from the tissue-penetrating catheter56by advancing the push rod76within the tissue-penetrating catheter56.

Desirably, the distal end56aof the tissue-penetrating catheter56assumes a nonlinear shape in a relaxed position. That is, preferably, when no restraining force is present on the distal end56aof the tissue-penetrating catheter56, the distal end56amoves into a nonlinear orientation. Preferably, in a relaxed position, the distal end56ais arcuate or curved and, more preferably, assumes a generally helical shape. The helix angle, radius and length of the distal end56amay be altered to suit the properties of the tissue that to be remodeled. Preferably, at least the distal end56aof the tissue-penetrating catheter56preferably is constructed from a suitable shape memory material that is configured to have a desired shape in its relaxed position, such as a nickel titanium alloy (NiTi), for example.

With such an arrangement, when the tissue-penetrating catheter56is in its stowed position, the access catheter54constrains the distal end56ainto a generally straightened orientation, or a shape that generally matches the shape of the distal end54aof the access catheter54at a given time. However, when the tissue-penetrating catheter56is moved to its protruding position, the distal end56atends to move toward its predefined relaxed shape. In use, outside forces may inhibit the distal end56aof the tissue-penetrating catheter56from reaching its full relaxed orientation, such as forces imposed by the tissue in which the distal end56ais penetrating. Preferably, the relaxed shape of the distal end56aof the tissue-penetrating catheter56is configured such that the shape assumed by the distal end56awill be generally as desired in the presence of anticipated restraining forces, such as those originating from soft tissue of a patient, for example. Furthermore, although a helical shape is preferred, in other applications other shapes may be desirable, as will be appreciated by one of skill in the art. Preferably, the tip of the distal end56aof the tissue-penetrating catheter is angled relative to a longitudinal axis of the catheter56to permit the distal end56aof the tissue-penetrating catheter56to pierce soft tissue. Other suitable tip shapes that would permit the catheter56to pierce or penetrate soft tissue may also be used.

Preferably, the tissue remodeling clip74is configured to be movable between a nonlinear, relaxed position and a biased, or straightened position. Thus, the clip74preferably is constructed from a shape memory material, such as NiTi. When stowed within the tissue-penetrating catheter56, preferably the clip74is biased into a generally linear orientation or a shape that generally matches the shape of the distal end56aof the tissue-penetrating catheter56. When deployed from the tissue-penetrating catheter56, the clip74moves toward its relaxed position wherein, preferably, a first end74aof the clip74is resiliently biased to move toward a second end74b, as illustrated inFIG. 6a. In the illustrated arrangement, the clip74in a relaxed position assumes a generally circular shape. However, the clip74may be configured to assume other suitable shapes in its relaxed position.

The illustrated clip74may have a diameter from between about 0.005 inches to about 0.05 inches. The circular loop defined by the clip74in its relaxed position may have a diameter from about 0.06 inches to about 0.5 inches. A length of the clip74may be from about 0.5 inches to about 2 inches. These dimensions are presently preferred for a clip74configured to remodel the left ventricle of a patient's heart. In other applications, other dimensions may be desirable. The clip74may be shaped by winding a work piece on a mandrel and then exposing the work piece to a heat cycle of about 500 degrees centigrade for a period of between about 10 minutes to about 60 minutes, depending on the strength, spring rate and oxide layer desired. Furthermore, other suitable methods of shaping the clip74may also be used.

As illustrated inFIG. 6c, when implanted into soft tissue T, the clip74moves toward its relaxed position such that the first end74aapplies a force to the tissue T at a first location and the second end74bapplies a force to the tissue T at a second location spaced from the first location to remodel the soft tissue T. As discussed above with respect to the distal end56aof the tissue-penetrating catheter56, in use the clip74may not move completely to its relaxed position due to restraining forces, such as forces imposed by the soft tissue. Thus, the tissue remodeling position of the clip74may fall somewhere between its straightened position and its relaxed position. Furthermore, the ends74a,74bof the clip74may remain embedded within the soft tissue T. However, preferably the clip74does not protrude through an external surface of the tissue wall (the non-entry side of the wall). That is, when the clip74is implanted within a ventricle of a heart, preferably, the clip74enters the heart wall from a location internal the ventricle and does not pass through an outer surface of the heart wall.

FIGS. 7a-7dillustrate a modification of the tissue remodeling clip74and is generally referred to by the reference numeral80. The clip80includes a pledget at each of its first and second ends80a,80b. The pledgets82preferably are relatively thin, circular members which have a diameter substantially larger than a diameter of the clip80when the pledgets82are in an expanded position (FIGS. 7a,7band7d). Therefore, the pledgets82inhibit the ends80a,80bof the clip80, once passed completely through soft tissue T, from pulling back through the surface of the tissue T. Thus, the ends80a,80bof the clip80preferably remain exposed from the tissue T. Preferably, the pledgets82are collapsible to permit the clip80to be initially implanted into the tissue T, as illustrated inFIG. 7c.

In a preferred embodiment, the pledgets82may be constructed from a piece of polymer material, such as Dacron, that is cut into a circular shape with a central aperture. The pledgets82may be placed over the ends80a,80bof the clip80and the ends80a,80benlarged to retain the pledgets82on the clip80. The enlarged ends may be formed by resistance spot welding, laser welding, or other suitable methods. Further, the enlarged ends may be created by additional members that are separate from, and secured to, the clip80.

Another modification of the clip74ofFIG. 6is illustrated inFIGS. 8a-8cand is referred to by the reference numeral90. The clip90ofFIGS. 8a-8cincludes a plurality of barbs92on each of the first and second ends90a,90b. The barbs92are configured to penetrate tissue to inhibit movement of the clip90relative to the tissue. The barbs92(and ends90a,90b) may be embedded in the tissue T when the clip90is implanted, as shown inFIG. 8c, or, alternatively, may be exposed from the tissue T. The barbs92may be created by a laser cutting technique, electrical discharge machining (EDM), mechanical cutting techniques, or other suitable processes. In addition, other suitable stabilizing members or arrangements to inhibit movement of the clips74,80,90relative to the tissue into which they are implanted may also be used. Furthermore, although the illustrated clips74,80,90are circular in cross-sectional shape, other suitable shapes may also be used, such as a rectangular or elliptical cross-section, for example.

FIGS. 9-12illustrate a preferred method for utilizing the system50ofFIGS. 1-8to remodel soft tissue of a patient P and, preferably, to remodel the left ventricle of the patient's P heart H. In a preferred application of the method illustrated inFIGS. 9-12, access to the left ventricle of the heart H is achieved through the patient's vasculature V from an insertion site in the femoral artery F. If desired, a sleeve (not shown) may be inserted into the femoral artery F to provide access for the catheter52. Alternatively, other methods of accessing the left ventricle, preferably using a percutaneous approach, may also be used.

With reference toFIG. 10, the catheter52is illustrated accessing the left ventricle LV of the patient's heart through the aorta A. The catheter52may be routed to the left ventricle LV by any suitable method. For example, as described above, the catheter52may be steerable to permit a user to navigate the patient's P vasculature using a suitable imaging technique. For example, preferably, the method is performed by a cardiologist in a cathlab setting using a transesophageal echocardiogram (TEE) or angiographic fluoroscopy imaging technique to accomplish each of the steps described herein that take place within the patient P. In addition, other imaging techniques may also be used. If desired, a guide wire (not shown) may be routed to the left ventricle LV and the catheter52may be introduced to the left ventricle LV over the guide wire.

As will be appreciated by one of skill in the art, a human heart H includes a right atrium RA, a left atrium LA, a right ventricle RV and a left ventricle LV. The tricuspid valve TV separates the right atrium from the right ventricle and the pulmonary valve PV separates the right ventricle from the pulmonary artery PA. The mitral valve MV separates the left atrium LA from the left ventricle LV and they aortic valve AV separates the left ventricle LV from the aorta A.

As illustrated inFIG. 10, in the preferred method, the balloon64is inflated so that the catheter assembly52, and access catheter54in particular, may be held against the wall of the left ventricle LV without causing damage thereto. Thus, preferably the balloon64supports a distal tip of the access catheter54at least slightly spaced from the wall of the left ventricle LV. The balloon64may also contact the wall of the left ventricle LV adjacent the desired remodeling site to inhibit the distal end54aof the access catheter54from moving once it is positioned.

With reference toFIG. 11a, once the access catheter54is guided to a desired position within the left ventricle LV, the tissue penetrating catheter56may be moved from its stowed position within the access catheter54towards its protruding position such that the tissue-penetrating catheter56creates a passage within the wall of the left ventricle LV. Preferably, the tissue-penetrating catheter56creates a passage that has a shape generally corresponding to the relaxed shape of the distal end56aof the tissue-penetrating catheter56. If desired, one or both of the access catheter54and the tissue-penetrating catheter56may be rotated to assist the tissue-penetrating catheter56in creating a passage within the wall of the left ventricle, as illustrated by the arrows94inFIG. 11b.

With reference toFIG. 11c, once the passage has been created within the wall of the left ventricle LV, the push rod76may be used to hold the clip74in position while permitting the tissue-penetrating catheter56to be withdrawn from the passage and into the access catheter54, thus leaving the clip74in place within the passage in the wall of the left ventricle LV. Alternatively, the tissue-penetrating catheter56may be withdrawn from the passage, along with the clip74, and the push rod76used to subsequently deploy the clip74into the preformed passage. The preferred method of deploying the clip74may depend on individual user preference, the shape of the clip74or the properties of the soft tissue T, among other considerations.

As illustrated inFIG. 11c, with the distal end of the access catheter54and balloon64pressed against the wall of the left ventricle LV, the clip74is inhibited from moving substantially toward its relaxed position. With reference to Figure lid, once the access catheter54is pulled away from the wall of the left ventricle LV, the tissue remodeling clip74may move substantially toward its relaxed position, thus bringing the ends74a,74bof the clip74toward one another to draw the portions of the ventricle wall associated with each end74a,74btoward one another. Accordingly, the implantation of the clip74thereby remodels and preferably reduces the volume of the left ventricle LV. In the illustrated arrangement, the clip74is implanted in the free wall of the left ventricle LV. That is, the clip74is implanted into tissue defining a wall of the ventricle other than the septal wall. However, in some applications it may be desirable to remodel the septal wall, such as when performing a septal defect repair. Thus, the present systems disclosed herein may be used to remodel the septal wall, or may be appropriately modified to remodel the septal wall, if so desired.

With reference toFIG. 11c, once the passage has been created within the wall of the left ventricle LV, the push rod76may be used to hold the clip74in position while permitting the tissue-penetrating catheter56to be withdrawn from the passage and into the access catheter54, thus leaving the clip74in place within the passage in the wall of the left ventricle LV. Alternatively, the tissue-penetrating catheter56may be withdrawn from the passage, along with the clip74, and the push rod76used to subsequently deploy the clip74into the preformed passage. The preferred method of deploying the clip74may depend on individual user preference, the shape of the clip74or the properties of the soft tissue T, among other considerations.

FIG. 12illustrates a plurality of remodeling clips80implanted within the wall of the left ventricle to remodel the left ventricle LV and, preferably, reduce the volume of the left ventricle LV. In some applications, only one clip74,80,90may be desired and, in other applications, a plurality of clips74,80,90may be used depending on what level of remodeling, or reduction in volume, is desired. In a preferred method, enough clips74,80,90are implanted to substantially completely fold away the akinetic portion of the ventricle tissue. However, it is contemplated that one of skill in the art will be able to determine a suitable number of clips74,80,90to be implanted depending on a particular application, the level of remodeling desired, the properties of the clip74,80,90, and the properties of the soft tissue, among other considerations.

FIGS. 13-17illustrate a second embodiment of a tissue remodeling system, generally referred to by the reference numeral100. Preferably, the system100is a catheter-based tissue remodeling system that is configured to facilitate the remodeling of soft tissue of a patient at a desired site that is accessed through the patient's vasculature. The illustrated system100is configured to remodel a patient's heart and, preferably, reduce the volume of the left ventricle of the heart. However, as described above, the systems and methods disclosed herein may be used to otherwise manipulate, gather, fold, tie or join soft tissue, such as to achieve a closing of a tissue cavity, for example.

The system100includes a catheter assembly102including a plurality of coaxial catheter bodies. In the illustrated arrangement, the catheter assembly102includes a guide catheter, or access catheter104. A delivery catheter106is movable within a lumen of the access catheter104. Preferably, a guide wire108is movable within a lumen of the delivery catheter106. The catheter102is configured to deliver an implant, or collapsible tissue anchor110, to a desired tissue remodeling site, such as the left ventricle of the heart in the illustrated arrangement, for example.

Preferably, the access catheter104is substantially similar to the access catheter54of the system50ofFIGS. 1-8. The access catheter104includes a distal end104aconfigured to be introduced into the left ventricle of a patient's heart and a proximal end104bdefining a handle. The access catheter104may be of any suitable size, shape, and length to extend from the desired remodeling site to a site external the patient through a suitable route. For example, the illustrated catheter102preferably is sized to extend from a left ventricle of a patient's heart to an external site adjacent the patient's femoral artery. Preferably, the access catheter104may have an outer diameter of about26F and an inner (lumen) diameter of about23F. However, other suitable dimensions may be used to suit a desired application. Furthermore, the catheter102may be constructed of any suitable material for use in a medical catheter application, as described above.

The delivery catheter106is configured to be axially movable within the access catheter104. The delivery catheter106includes a distal end106a, which is configured to support the tissue anchor110, and a proximal end106bdefining a handle. The delivery catheter106may be constructed from any suitable material, as described above, and preferably has an outer diameter of about 0.25 inches and an inner (lumen) diameter of about 0.125 inches. However, the dimensions may be adjusted to suit a desired application.

The guide wire108preferably is configured to be deliverable through the vasculature of a patient to the left ventricle as an individual component to permit the access catheter104and delivery catheter106to be introduced into the left ventricle by being passed over the previously placed guide wire108. Preferably, the guide wire108includes a tip111at its distal end108athat is configured to be atraumatic to tissue that it comes into contact with. Desirably, the guide wire108also includes a proximal end108b, which defines a handle or other structure that permits a user to manipulate the guide wire108.

With reference toFIGS. 14 and 15, desirably, the delivery catheter106includes a docking tip112at its distal end106a. Preferably, the tip112defines an outer surface that has a reduced diameter relative to a diameter of the outer surface of the remainder of the delivery catheter106. The docking tip112is sized and shaped to support a proximal end of the tissue anchor110thereon. Thus, preferably, an outer diameter of the tissue anchor110is generally equal to an outer diameter of the delivery catheter106such that when the tissue anchor110is positioned on the tip112, the transition between the catheter106and the tissue anchor110is relatively seamless. Although the collapsible tissue anchor110is illustrated as surrounding the docking tip112in the illustrated arrangement, other suitable arrangements to interconnect the tissue anchor110and the delivery catheter106may also be employed.

Preferably, the delivery catheter106includes a retention mechanism114that is configured to secure the tissue anchor110to the distal end106aof the delivery catheter106and selectively release the tissue anchor110from the delivery catheter106. In the illustrated arrangement, a retention wire116is slidably received within a passage118defined by a wall of the delivery catheter106. A distal end116aof the retention wire116is configured to extend radially outwardly relative to the catheter106, from the passage118, into an aperture120of the tissue anchor110. A proximal end116bof the retention wire116includes a handle, or other suitable structure, which permits a user to retract the retention wire116within the passage118to release the tissue anchor110from the delivery catheter106.

Alternatively, other suitable arrangements to retain and selectively release the tissue anchor110may also be employed. In some arrangements, for example, the tissue anchor110and catheter106may cooperate through a snap-fit arrangement in which an interference surface of the catheter106contacts an interference surface of the tissue anchor110to inhibit the anchor110from unintentionally becoming separated from the catheter106. In such an arrangement, once the tissue anchor110is implanted within soft tissue, the anchor110may be automatically separated from the catheter106when a pulling force is applied to the catheter106, as the tissue anchor110preferably will remain in place within the tissue.

FIGS. 16aand16billustrate the tissue anchor110removed from the delivery catheter106. Preferably, the tissue anchor110includes a base portion130and a plurality of legs132which extend from the base portion130. Desirably, the tissue anchor110includes between about 2 and 8 legs132and, preferably, between about 3 to 5 legs132. The illustrated tissue anchor110includes three legs132. However, other suitable numbers of legs132may be provided in accordance with the requirements an individual application.

Preferably, the tissue anchor110is a hollow member having a relatively thin wall thickness dimension. Preferably, the tissue anchor110is constructed of a metal material and, more preferably, from a shape memory material, such as NiTi, for example. Desirably, the base130is generally cylindrical in shape and the legs132, preferably, are unitary with the base130and extend from the wall thereof. The base130may have an outer diameter of about 0.25 inches and an inside diameter of about 0.188 inches, for an anchor110configured to be implanted into a left ventricle of a patient's heart. However, the dimensions may be altered to achieve desired properties of the anchor110to suit an individual application, such as the closure of a cavity or hole, for example. The legs132may be created by cutting away material from an initial work piece, or sleeve, using a laser cutting method, or other suitable fabrication method.

Preferably, the legs132are movable, or flexible, relative to the base130between a relaxed position, wherein the legs132extend radially outward from the base130, to a collapsed position, or tissue-remodeling position, wherein the legs132are biased inwardly from their relaxed position. Preferably, in the collapsed position, the legs132are generally aligned with the wall of the base130. However, in some applications, the legs132may extend radially outward from the base130, or radially inward from the base130, in the tissue-remodeling position.

With reference toFIG. 17c, preferably, a retention member134is configured to retain the legs132in the tissue remodeling position. In the illustrated arrangement, the retention member134is in the form of a sleeve which slides over an outer surface of the legs132, as is described in greater detail below. However, other suitable retention mechanisms may also be employed.

Each of the legs132preferably includes a pointed tissue piercing end136to permit the legs132to penetrate soft tissue of a patient, such as the wall of the left ventricle of the patient's heart. In addition, preferably the legs132include one or more barbs138, which are configured to permit the legs132to enter soft tissue, in a first direction, and inhibit the legs132from being removed from the soft tissue in the opposite direction. Thus, once the legs132have penetrated the soft tissue, preferably, the tissue anchor110remains embedded in the tissue.

Desirably, the tissue anchor110is configured to inhibit the retention member134from inadvertently becoming dislodged from the tissue anchor110. In the illustrated arrangement, the base130includes a plurality of pawls, or tabs140, which are configured to permit the retention member134to move toward the distal end of the tissue anchor110and inhibit the retention member134from moving away from the distal end, toward the proximal end of the tissue anchor110past the tabs140. Desirably, the tabs140are generally semi-circular in shape and comprise an outwardly-bent portion of the material of the base130portion of the tissue anchor110. Thus, the tabs140bend inwardly, into general alignment with the base130, to permit the retention sleeve134to pass over. Once the retention sleeve134has passed over the tab140, it returns to its outwardly-bent position to interfere with an attempt of the retention sleeve134in moving back over the tab140, as illustrated inFIG. 17c. In some arrangements, tabs may also be defined by the legs132. Furthermore, in an alternative arrangement, the tabs140may be defined by members that are separate from, and attached to, the tissue anchor110.

In the illustrated arrangement, the base130includes several rows of tabs140wherein each row includes multiple tabs140arranged around the circumference of the base130. In the illustrated arrangement, the tissue anchor110includes three rows of tabs140, wherein each row includes three tabs140equally spaced about a circumference of the base130. However, other suitable arrangements to permit unidirectional movement of the retention member134may also be used.

FIGS. 17athrough17cillustrate the tissue anchor110in several states of deployment from the catheter assembly102. With reference toFIG. 17a, desirably the delivery catheter106is positioned within the access catheter104such that the tissue anchor110is substantially entirely enclosed within the access catheter104and constrained thereby into a collapsed position.

With reference toFIG. 17b, when the tissue anchor110is deployed from the access catheter104, the legs132are permitted to move toward their relaxed position. It should be noted that the radial expansion of the legs132toward their relaxed position may be influenced by the distance of which the tissue anchor110is exposed from the access catheter104. In some applications, legs132of the tissue anchor110may be completely deployed from the access catheter104prior to the legs132contacting soft tissue. Thus, in the absence of any other restraining force, the legs132would be in their fully relaxed position when contact with the soft tissue is made. In other applications, however, the legs132may be retained partially within the access catheter104so that the legs132are constrained from moving to their fully relaxed position. Accordingly, the diameter of a circle defined by the legs132(or the distance between the legs132and an axis of the catheter104) may be altered as desired prior to contact with the soft tissue. In addition, other methods of facilitating the tissue anchor110in grabbing a portion of soft tissue of a desired size or shape may also be used.

With reference toFIG. 17c, the retention member, or locking sleeve134, may be slid over the delivery catheter106and on to the tissue anchor110by a pusher catheter142. The retention sleeve134may be pushed a sufficient distance on to the tissue anchor110to move the legs132toward a tissue remodeling position to achieve a desired amount of remodeling. Desirably, the tabs140inhibit the retention sleeve134from becoming disengaged with the tissue anchor110. Alternatively, the legs132may be moved toward a tissue-remodeling position by another member and the retention sleeve134may be used simply to retain the legs132in the desired tissue-remodeling position.

FIGS. 18-22illustrate a preferred method of remodeling soft tissue of a patient using the system100ofFIGS. 13-17. The illustrated method utilizes the system100to remodel the left ventricle of a patient's heart and, preferably, to reduce the volume of the left ventricle. Desirably, access to the left ventricle is gained through the patient's vasculature beginning at an insertion site in the femoral artery F, as shown inFIG. 9. However, other methods of gaining access to the left ventricle may also be used.

With reference toFIG. 18, the guide wire108may be advanced through the patient's vasculature, from the femoral artery F, to enter the left ventricle LV through the aorta A using a suitable imaging technique, as described above. The guide wire108is positioned preferably such that its distal end108acontacts a portion of the wall of the left ventricle LV where remodeling is desired. Subsequently, the delivery catheter106and access catheter104may be advanced over the guide wire108, either individually or together, until the distal end of each approaches the wall of the left ventricle LV. Preferably, the distal end of the access catheter104and delivery catheter106are spaced from the wall of the left ventricle LV as illustrated inFIG. 18.

With reference toFIG. 19, the delivery catheter106may be advanced relative to the access catheter104and guide wire108such that the tissue anchor110is deployed therefrom. Once the tissue anchor110is at least partially deployed from the access catheter104, the legs132may move toward their relaxed, or radially outward position. As described above, the distance that the tissue anchor110is deployed from the access catheter104, which preferably applies a restraining force to the legs132, influences a distance that the legs132may expand from a center axis of the catheter104. Such a technique may be used to determine the amount of tissue grasped by the legs132of the tissue anchor110. In the illustrated arrangement, the tissue anchor110is shown completely deployed from the access catheter104.

With reference toFIG. 20, the delivery catheter106and, if desired, the access catheter104, may be moved relative to the guide wire108toward the wall of the left ventricle LV until the tips136of the legs132of the tissue anchor110penetrate the wall of the left ventricle LV. Desirably, with the illustrated tissue anchor110, the legs132do not penetrate an outer surface of the heart H. However, in some arrangements, it may be desirable that the legs132pass completely through the wall of the heart H. Once the legs132have been entered the wall of the left ventricle LV, the barbs138preferably inhibit the legs132from being removed therefrom.

With reference toFIG. 21, the access catheter104may be removed from the delivery catheter106to permit the locking clip134to be positioned over the delivery catheter106. The pusher catheter142may then be used to move the locking ring134to the distal end of the delivery catheter and over the tissue anchor110to move the legs132toward their tissue-remodeling position. As described above, the locking sleeve134may be moved on to the tissue anchor110a sufficient distance to move the legs132until a desired level of remodeling is accomplished. The pusher catheter142may then be removed and the tabs140of the tissue anchor110inhibit the locking ring134from becoming disengaged with the tissue anchor110and thereby retain the tissue anchor110in its tissue remodeling position. Alternatively, the access catheter104may be adapted to carry and deploy the locking sleeve134to eliminate the need for a separate pusher catheter142.

With reference toFIG. 22, the tissue anchor110is shown in its tissue remodeling orientation configured to reduce the volume of the left ventricle LV of the patient's heart H. Once the retaining sleeve134is positioned as desired on the tissue anchor110, the pusher catheter142and guide wire108may be removed, leaving the tissue anchor110implanted in place in the left ventricle LV. If desired, more than one tissue anchor110may be deployed using a similar method to create a plurality of tissue folds, depending on the level of remodeling or volume-reduction desired. The multiple tissue anchors110may be arranged relative to one another in any suitable orientation to achieve a desired degree or shape of tissue remodeling. For example, the tissue anchors110may be arranged along a line generally passing through the tissue area that is desired to be remodeled.

FIGS. 23-31illustrate another embodiment of a tissue remodeling system generally referred to by the reference numeral150. The tissue remodeling system150is configured to deliver a suture to soft tissue of a patient to facilitate remodeling of the soft tissue of a patient. Preferably, a plurality of sutures are delivered to accomplish the tissue remodeling. The illustrated system150is configured to remodel of the left ventricle of a patient's heart and, preferably, to reduce the volume of the left ventricle using a percutaneous approach through the patient's vasculature. Preferably, the vasculature is accessed through an insertion site in the patient's femoral artery. In addition, other remodeling, tissue joining or tying can be accomplished with the illustrated system150or modifications thereof.

The illustrated system150includes a catheter assembly152including a guide catheter, or access catheter154, and a suture delivery catheter156, which is axially slidable within the access catheter154. The catheter assembly152is configured to be insertable into a patient's vasculature and, preferably, directed to the patient's left ventricle to facilitate a remodeling of the ventricle.

The access catheter154preferably includes a distal end154aconfigured to be insertable into the patient's left ventricle. The proximal end154bof the access catheter154is configured to remain outside of the patient and, preferably, defines a handle. The access catheter154may be constructed from any suitable material, as described above, and may be of any suitable size and shape. In the illustrated embodiment, the access catheter154has an outer diameter of up to about26F and an inner (lumen) diameter of about23F. In addition, if desired, the access catheter154may be steerable, as described in connection with the catheter54ofFIGS. 1-3.

The suture delivery catheter156includes a distal end portion156athat is configured to deliver an end of a suture through the soft tissue of a patient and, preferably, permit the end of the suture to be removed from the patient along with the catheter156. A proximal end156bof the suture delivery catheter156is configured to be exposed from the access catheter154and, preferably, defines a handle. The suture delivery catheter156may be constructed from any suitable material, as described above, and may be of any suitable size or shape. In the illustrated arrangement, the catheter156may have an outer diameter of about22F. However, the catheter156may be constructed with other suitable dimensions as well.

The distal end156aof the suture delivery catheter156preferably defines a cavity, or recess158, which is configured to receive a portion of the wall of the patient's left ventricle. In one arrangement, the recess158may be generally semi-cylindrical in shape. Once the soft tissue is positioned within the recess158, the suture delivery catheter156is configured to permit an end of the suture to be passed through the tissue. Preferably, the recess158is sized such that the suture passes through an inner surface of the wall of tissue, without passing through the outer surface of the wall. To assist in positioning tissue within the recess158, preferably, a vacuum passage160communicates with the recess158at one end and extends through a wall of the suture delivery catheter156to the proximal end156b.A vacuum source162preferably is connected to the vacuum passage160by a suitable connection.

Preferably, the catheter152also includes a stabilizer mechanism164that is configured to assist in stabilizing the catheter152within the left ventricle while the suture is being passed through the wall of the left ventricle. The stabilizer mechanism164may also be useful to assist in positioning the distal end152aof the catheter152. The illustrated stabilizer mechanism164includes a stabilizer wire166, a portion of which is exposed in the form of a loop near a distal end156aof the suture delivery catheter156. A distal end166aof the stabilizer wire166preferably is embedded in a distal end156aof the suture delivery catheter156. From the distal end,166a, the stabilizer wire166extends in a loop external to the suture delivery catheter156until it passes into an opening168in the suture delivery catheter156and extends to a proximal end of the suture delivery catheter156through a passage170.

A proximal end of the stabilizer wire166defines a handle. Thus, a user may push the handle of the proximal end166bof the stabilizer wire166to enlarge the size of the loop of the stabilizer wire166at the distal end156aof the suture delivery catheter156. Conversely, if the handle of the proximal end166bof the stabilizer wire166is pulled away from the proximal end156bof the suture delivery catheter156, the size of the loop is reduced. The stabilizer wire166may be manipulated to vary size of the exposed loop to press against an inner surface of the left ventricle to maintain the distal end156aof the suture delivery catheter156in contact with a wall of the left ventricle. Furthermore, preferably, the stabilizer wire166may be retracted completely, or nearly completely, within the suture delivery catheter156so as not to interfere with movement of the catheter156within the access catheter154.

Preferably, the system150also includes a suture delivery device172. The suture delivery device172preferably includes a passage174defined by the body of the suture delivery catheter156. Preferably, a distal end174aof the suture passage174communicates with the recess158and a proximal end174bof the suture passage174opens from a proximal end of the suture delivery catheter156.

A push rod176extends through the suture passage174. A distal end176aof the push rod176carries a releasable tissue penetration member, or needle178, which is configured to carry one end of a suture180. A proximal end176bof the push rod176defines a handle that is external of the suture delivery catheter156. Thus, the suture passage174preferably is sized and shaped to accommodate both a suture180and the push rod176. In the illustrated arrangement, the suture passage174may have a diameter of about 0.065 inches to accommodate a push rod176having a diameter of about 0.045 inches (17 L Gauge). However, the passage174and push rod176may have other suitable dimensions to suit a desired application.

In the illustrated arrangement, the needle178and the push rod176are connectable by a snap-fit arrangement, which is configured to retain the needle178on the push rod176, once assembled, and permit the needle178to be selectively removed from the push rod176upon application of a sufficient removal force. Furthermore, an end of the suture180may be coupled to the needle178in any suitable manner. In the illustrated embodiment, the suture passes through an aperture181in the push rod176(FIG. 24) before being secured to the needle178.

The suture delivery catheter156preferably also defines a needle trap182on an end of the recess158opposite the suture passage174. Desirably, the needle trap182is aligned with the suture passage174such that the needle178will enter the trap182once it has passed through the recess158. In the illustrated arrangement, the need trap182is an elongate passage configured to receive the needle178and inhibit the needle178from being released from the trap182. The needle trap182may be of any suitable construction to permit the needle178to enter the trap182in a first direction and inhibit the needle178from being removed. In one arrangement, the trap182may comprise one or more oriented ribs, barbs or surface features that exhibit slight resistance to entry of the needle178, but exhibit significantly greater resistance to the removal of the needle178. In addition, other suitable arrangements may also be used.

Thus, once positioned within the trap182, the needle178remains in the trap182and is disconnected from the push rod176as the push rod176is retracted from the suture delivery catheter156. Thus, the needle178and suture180may be pushed through the tissue occupying the recess158, entering the tissue at a first location and exiting the tissue at a section location, until the needle178is received within the trap182. The push rod176may then be retracted from the suture delivery catheter156leaving the needle178within the trap182and the suture180extending through the tissue. The suture180may be pulled through the tissue along with the suture delivery catheter156as the suture delivery catheter156is removed from the left ventricle, as is described in greater detail below. As a result, both ends of the suture180will be external the patient, with the suture passing through a section of tissue. Applying tension to both ends of the suture180will tend to draw the tissue portions associated with the entry and exit locations of the suture180towards one another.

With reference toFIGS. 26-28, the tissue remodeling system150also includes a catheter190configured to deliver a retaining clip192, which is configured to retain at least one suture180, and preferably a plurality of sutures180, in a gathered position, as is described in greater detail below. The retaining clip delivery catheter190preferably includes an outer catheter body194and an inner catheter body196. The outer catheter194and inner catheter196are coaxial with one another and configured to cooperate to deliver the retaining clip192through the access catheter154. In the illustrated arrangement, the outer catheter194may have an outer diameter of about22F, with a lumen of about17F. The inner catheter196may have an outer diameter of about12to14F, with a lumen of about10F. Other suitable dimensions may be used to suit an individual application.

With reference toFIG. 27, preferably, the retaining clip192is supported on a distal end portion196aof the inner catheter196. A distal end portion194aof the outer catheter194is positioned adjacent the retaining clip192. The outer catheter194is movable relative to the inner catheter196to selectively push the retaining clip194off of the distal end196aof the inner catheter196.

With reference toFIGS. 28aand28b, desirably the retaining clip192is formed from a shape memory material, such as NiTi, for example, such that the clip192is moveable from a biased opened position, such as when supported on the inner catheter196, to a relaxed position, wherein the retaining clip192coils over on itself, as illustrated inFIG. 28b. When in its relaxed position, the retaining clip192is configured to retain one or more sutures180in a gathered orientation, as is described in greater detail below.

With reference toFIG. 29, preferably, both the suture delivery catheter156and the retaining clip delivery catheter190may be removed from the access catheter154. A knot pusher200may be used to push a knot202from external a proximal end154bof the access catheter154to external a distal end154aof the access catheter154and, preferably, against the retaining clip192. Thus, one or more knots202may be used to inhibit, or prevent, the retaining clip192from moving relative to the sutures180to advantageously retain the sutures180in a gathered orientation. The knot pusher200preferably is of a conventional construction comprising an elongate body of stainless steel having distal tip formed into a loop, as will be appreciated by one of skill in the art. Other suitable methods or devices to move a knot202along the sutures180or otherwise inhibit undesired movement of the retaining clip192may also be used.

The tissue remodeling system150preferably also includes a suture cutting device210. The suture cutter assembly210preferably includes a catheter212having a distal end212aand a proximal end212b. Desirably, the proximal end212bdefines a handle. The catheter212preferably includes a distal end section214and a proximal end section216. Preferably, the proximal end216includes a semi-cylindrical passage218and a suture passage220. A push rod222extends through the passage218and, preferably, is also semi-cylindrical in shape to generally match the shape of the passage218. A distal end222aof the push rod222preferably includes a cutting surface223and a proximal end222bof the push rod defines a handle.

The distal end section214preferably also includes a semi-cylindrical passage226that is closed by a plug228. Further, the distal end section214preferably includes a suture passage230. In the illustrated arrangement, the distal end section214defines a working space232between the passage226and suture passage230of the distal end section214and the passage218and suture passage220of the proximal end section216. Desirably, the distal end section214is oriented such that the suture passage220and the suture passage230are directly opposite one another. The suture180may be passed through the passages220and230so that the suture180will pass through the working space232past the cutting surface223of the push rod222. The push rod222may be advanced to cut the suture between the cutting surface223of the distal end222aand the plug228. Alternatively, the distal end section214may be rotatable relative to the proximal section216such that the suture passages220and230may be selectively aligned, the suture passed through the passages220and230, and the distal end section214rotated relative to the proximal section216such that the suture passages220and230are opposite one another so that the suture may be cut. In addition, other suitable devices or methods may also be used to cut the one or more sutures180, if desired.

With reference toFIGS. 32-40, a preferred method of remodeling tissue with the system150ofFIGS. 23-31is illustrated. As described above, the preferred method is utilized to reduce a volume of the left ventricle LV of the heart H of a patient P. With reference toFIG. 32, desirably, the system150is configured to be introduced into the vasculature V of the patient P at a desired site. In the illustrated arrangement, the catheter152is introduced through the femoral artery F of the patient P and is guided to the left ventricle LV.

With additional reference toFIGS. 33aand33b, the suture delivery catheter156is positioned within the left ventricle LV so that the suture may be passed through a desired site of the wall of the left ventricle LV. The suture delivery catheter156may be positioned by steering one or both of the access catheter154and suture delivery catheter156. In addition, the stabilizing wire166may be used to assist in positioning the suture delivery catheter156and retaining the suture delivery catheter156in a desired position within the left ventricle LV.

Once positioned as desired, the vacuum source162may be activated to draw tissue within the recess158(FIG. 24) of the suture delivery catheter156. The push rod166may then be advanced to push the needle178through the tissue occupying the recess158. The push rod166preferably is advanced until the needle178enters the trap182whereby the suture180is passed through the tissue within the recess158.

With referenceFIG. 34aand34b, the stabilizing wire166may be retracted and the vacuum source162deactivated. The suture delivery catheter156may be withdrawn thereby pulling the suture180through the tissue and removing the end of the suture180along with the suture delivery catheter156. Thus, once the suture delivery catheter156is completely removed from the patient's vasculature, both ends of the suture180will be external the patient with the suture180passing through a section of the tissue of the left ventricle LV, entering the tissue at a first location and exiting the tissue at a second location spaced from the first location.

With reference toFIG. 35 and 36, preferably additional sutures180are positioned within the left ventricle in desired positions relative to the initial suture180. Preferably, the multiple sutures180are positioned such that, when drawn together, the tissue of the left ventricle will be drawn together along a desired suturing line around the diseased portion of the ventricle, which will reduce the volume of the ventricle. However, in some arrangements, a desired level of remodeling, tying or tissue joining may be accomplished with only one suture180.

With references toFIGS. 37-39, once a desired number of sutures180are placed within the left ventricle LV, the retaining clip delivery catheter190is advanced over the sutures180and within the access catheter154until a distal end of the retaining clip delivery catheter190is within the left ventricle LV. The retaining clip delivery catheter190is advanced until the sutures180are drawn together to reduce the volume of the left ventricle LV, preferably much like the closing of a pursestring suture. When the sutures180are drawn together to a sufficient degree, the outer catheter194may be advanced relative to the inner catheter196such that the retaining clip192is deployed therefrom, preferably substantially as described above with reference toFIG. 27.

FIG. 40illustrates the gathered sutures retained by the retaining clip192such that the volume of the left ventricle LV is reduced. Preferably, the left ventricle LV is reduced to a volume that approximates the normal size of the ventricle prior to the onset of heart disease, or that results in an acceptable level of performance. In one arrangement, the dyskinetic portion of the left ventricle LV is essentially eliminated from defining the working chamber of the ventricle LV. If the dyskinetic portion of the ventricle LV is large enough, the plurality of sutures180, in a drawn together orientation, create two chambers within the ventricle: a working chamber WC and a dormant chamber DC. Preferably, the sutures180draw the wall of the ventricle together to an extent that the chambers WC and DC are substantially isolated from one another. That is, although some minor amount of fluid communication may exist between the chambers WC and DC, the dormant chamber DC does not effectively contribute to the working volume of the ventricle LV.

As illustrated, preferably, a plurality of knots202are created within the sutures180and advanced to a position behind the retainer clip192to retain the sutures180in a drawn together position. Preferably, the knots202are advanced from external the patient P to behind the retainer clip192by a knot pusher, such as the knot pusher200described in relation toFIG. 29. However, other suitable methods or devices for creating knots, or otherwise retaining the retainer clip192in a desired position, may also be used. In addition, the ends of the sutures180are cut, preferably using a device substantially as described with respect toFIGS. 30 and 31. However, other suitable methods or devices for cutting the sutures180may also be used.

Although this invention has been disclosed in the context of certain preferred embodiments and examples, it will be understood by those skilled in the art that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. In particular, while the present tissue remodeling systems and methods have been described in the context of particularly preferred embodiments, the skilled artisan will appreciate, in view of the present disclosure, that certain advantages, features and aspects of the system may be realized in a variety of other applications, many of which have been noted above. Additionally, it is contemplated that various aspects and features of the invention described can be practiced separately, combined together, or substituted for one another, and that a variety of combination and subcombinations of the features and aspects can be made and still fall within the scope of the invention. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims.