Patent Description:
The invention is directed to a system for improving delivery of a heart implant, e.g., in the treatment of mitral valve regurgitation.

Treatments for mitral valve regurgitation are widely varied, encompassing both replacement valves as well as a number of approaches that facilitate repair and reshaping of the valve by use of an implant. While many such approaches rely on intravascular delivery of an implant, these often utilize a system of multiple catheters that are repeatedly exchanged, which is an often complex and time consuming process. To appreciate the difficulties and challenges associated with delivery and deployment of an implant within the human heart, it is useful to understand various aspects of the anatomy of the heart as well as conventional methods of deploying an implant for treatment of mitral valve regurgitation.

As can be seen in <FIG>, the human heart is a double-sided (left and right side), self-adjusting pump, the parts of which work in unison to propel blood to all parts of the body. The right side of the heart receives poorly oxygenated ("venous") blood from the body from the superior vena cava and inferior vena cava and pumps it through the pulmonary artery to the lungs for oxygenation. The left side receives well-oxygenation ("arterial") blood from the lungs through the pulmonary veins and pumps it into the aorta for distribution to the body.

The heart has four chambers, two on each side -- the right and left atria, and the right and left ventricles. The atriums are the blood-receiving chambers, which pump blood into the ventricles. The ventricles are the blood-discharging chambers. A wall composed of fibrous and muscular parts, called the interatrial septum separates the right and left atriums (see <FIG>). An anatomic landmark on the interatrial septum is an oval, thumbprint sized depression called the oval fossa, or fossa ovalis (FO), shown in <FIG>, which is a remnant of the oval foramen and its valve in the fetus and thus is free of any vital structures such as valve structure, blood vessels and conduction pathways. The synchronous pumping actions of the left and right sides of the heart constitute the cardiac cycle. The cycle begins with a period of ventricular relaxation, called ventricular diastole. The cycle ends with a period of ventricular contraction, called ventricular systole <NUM>. The heart has four valves (see <FIG>) that ensure that blood does not flow in the wrong direction during the cardiac cycle; that is, to ensure that the blood does not back flow from the ventricles into the corresponding atria, or back flow from the arteries into the corresponding ventricles. The valve between the left atrium and the left ventricle is the mitral valve. The valve between the right atrium and the right ventricle is the tricuspid valve. The pulmonary valve is at the opening of the pulmonary artery. The aortic valve is at the opening of the aorta.

At the beginning of ventricular diastole (i.e., ventricular filling), the aortic and pulmonary valves are closed to prevent back flow from the arteries into the ventricles. Shortly thereafter, the tricuspid and mitral valves open, as shown in <FIG>, to allow flow from the atriums into the corresponding ventricles. Shortly after ventricular systole (i.e., ventricular emptying) begins, the tricuspid and mitral valves close, as shown in <FIG> -- to prevent back flow from the ventricles into the corresponding atriums -- and the aortic and pulmonary valves open -- to permit discharge of blood into the arteries from the corresponding ventricles.

The opening and closing of heart valves occur primarily as a result of pressure differences. For example, the opening and closing of the mitral valve occurs as a result of the pressure differences between the left atrium and the left ventricle. During ventricular diastole, when ventricles are relaxed, the venous return of blood from the pulmonary veins into the left atrium causes the pressure in the atrium to exceed that in the ventricle. As a result, the mitral valve opens, allowing blood to enter the ventricle. As the ventricle contracts during ventricular systole, the intraventricular pressure rises above the pressure in the atrium and pushes the mitral valve shut.

As <FIG> show, the anterior (A) portion of the mitral valve annulus is intimate with the non-coronary leaflet of the aortic valve. Notably, the mitral valve annulus is near other critical heart structures, such as the circumflex branch of the left coronary artery (which supplies the left atrium, a variable amount of the left ventricle, and in many people the SA node) and the AV node (which, with the SA node, coordinates the cardiac cycle). In the vicinity of the posterior (P) mitral valve annulus is the coronary sinus and its tributaries. These vessels drain the areas of the heart supplied by the left coronary artery. The coronary sinus and its tributaries receive approximately <NUM>% of coronary venous blood. The coronary sinus empties into the posterior of the right atrium, anterior and inferior to the fossa ovalis, as can be seen <FIG>. A tributary of the coronary sinus is called the great cardiac vein, which courses parallel to the majority of the posterior mitral valve annulus, and is superior to the posterior mitral valve annulus by an average distance of about <NUM> +/- <NUM> millimeters (<NPL>).

When the left ventricle contracts after filling with blood from the left atrium, the walls of the ventricle move inward and release some of the tension from the papillary muscle and chords. The blood pushed up against the under-surface of the mitral leaflets causes them to rise toward the annulus plane of the mitral valve. As they progress toward the annulus, the leading edges of the anterior and posterior leaflet come together forming a seal and closing the valve. In the healthy heart, leaflet coaptation occurs near the plane of the mitral annulus. The blood continues to be pressurized in the left ventricle until it is ejected into the aorta. Contraction of the papillary muscles is simultaneous with the contraction of the ventricle and serves to keep healthy valve leaflets tightly shut at peak contraction pressures exerted by the ventricle.

In a healthy heart (shown in <FIG>), the dimensions of the mitral valve annulus create an anatomic shape and tension such that the leaflets coapt, forming a tight junction, at peak contraction pressures. Where the leaflets coapt at the opposing medial (CM) and lateral (CL) sides of the annulus are called the leaflet commissures. Valve malfunction can result from the chordae tendineae (the chords) becoming stretched, and in some cases tearing. When a chord tears, the result is a leaflet that flails. Also, a normally structured valve may not function properly because of an enlargement of or shape change in the valve annulus. This condition is referred to as a dilation of the annulus and generally results from heart muscle failure. In addition, the valve may be defective at birth or because of an acquired disease. Regardless of the cause, mitral valve dysfunction can occur when the leaflets do not coapt at peak contraction pressures, as shown in <FIG>. In such cases, the coaptation line of the two leaflets is not tight at ventricular systole. As a result, an undesired back flow of blood from the left ventricle into the left atrium can occur, commonly known as mitral regurgitation. This has two important consequences. First, blood flowing back into the atrium may cause high atrial pressure and reduce the flow of blood into the left atrium from the lungs. As blood backs up into the pulmonary system, fluid leaks into the lungs and causes pulmonary edema. Second, the blood volume going to the atrium reduces volume of blood going forward into the aorta causing low cardiac output. Excess blood in the atrium over-fills the ventricle during each cardiac cycle and causes volume overload in the left ventricle.

Mitral regurgitation is categorized into two main types, (i) organic or structural and (ii) functional. Organic mitral regurgitation results from a structurally abnormal valve component that causes a valve leaflet to leak during systole. Functional mitral regurgitation results from annulus dilation due to primary congestive heart failure, which is itself generally surgically untreatable, and not due to a cause like severe irreversible ischemia or primary valvular heart disease. Organic mitral regurgitation is seen when a disruption of the seal occurs at the free leading edge of the leaflet due to a ruptured chord or papillary muscle making the leaflet flail; or if the leaflet tissue is redundant, the valves may prolapse the level at which coaptation occurs higher into the atrium with further prolapse opening the valve higher in the atrium during ventricular systole. Functional mitral regurgitation occurs as a result of dilation of heart and mitral annulus secondary to heart failure, most often as a result of coronary artery disease or idiopathic dilated cardiomyopathy. Comparing a healthy annulus in <FIG> to an unhealthy annulus in <FIG>, the unhealthy annulus is dilated and, in particular, the anterior-to-posterior distance along the minor axis (line P-A) is increased. As a result, the shape and tension defined by the annulus becomes less oval (see <FIG>) and more round (see <FIG>). This condition is called dilation. When the annulus is dilated, the shape and tension conducive for coaptation at peak contraction pressures progressively deteriorate.

It is reported that twenty-five percent of the six million Americans who will have congestive heart failure will have functional mitral regurgitation to some degree. This constitutes the <NUM> million people with functional mitral regurgitation. In the treatment of mitral valve regurgitation, diuretics and/or vasodilators can be used to help reduce the amount of blood flowing back into the left atrium. An intra-aortic balloon counterpulsation device is used if the condition is not stabilized with medications. For chronic or acute mitral valve regurgitation, surgery to repair or replace the mitral valve is often necessary.

By interrupting the cycle of progressive functional mitral regurgitation, it has been shown in surgical patients that survival is increased and in fact forward ejection fraction increases in many patients. The problem with surgical therapy is the significant insult it imposes on these chronically ill patients with high morbidity and mortality rates associated with surgical repair.

Currently, patient selection criteria for mitral valve surgery are very selective and typically performed only on patients having normal ventricular function, generally good health, a predicted lifespan of greater than <NUM> to <NUM> years, NYHA Class III or IV symptoms, and at least Grade <NUM> regurgitation. Patients that do not meet these requirements, typically older patients in poor health, are not good candidates for surgical procedures, especially open surgical procedures. Such patients benefit greatly from shorter, less invasive surgical procedures that improve valve function, such as any of those described in <CIT>. However, such patients could benefit from further improvements in minimally invasive surgical procedures to deploy such valve treatment and repair implants. systems, reducing the complexity of delivery systems and duration of the procedures, as well as consistency, reliability and ease of use.

Thus, there is a need for further improvements that reduce the complexity of such delivery systems and improved methods of delivery that reduce the duration of the procedures, and improve the consistency, reliability and ease of use for the clinician, e.g., in the deployment of heart implants for treatment of mitral valve regurgitation.

<CIT> discloses devices and methods for percutaneous tricuspid valve repair.

<CIT> discloses methods, systems and devices for cardiac valve repair.

<CIT> discloses an endovascular system for arresting the heart.

<CIT> discloses a method of manufacture of a multi-lumen catheter.

<CIT> discloses an endovascular delivery system for magnetic compression vascular anastomosis.

<CIT> discloses devices, systems, and methods for improving the function of a heart valve, e.g., in the treatment of mitral valve regurgitation.

The invention provides delivery systems for heart implants that reshape a heart valve annulus, for example the mitral valve for treatment of mitral valve regurgitation.

The invention is defined in appended claim <NUM>.

Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.

<FIG> shows an example embodiment of a catheter-based delivery system in accordance with aspects of the invention. The delivery system utilizes a pair of magnetic catheters that are advanced from separate vascular access points and magnetically coupled across a tissue within the heart. The pair of catheters include a great cardiac vein (GCV) anchor delivery catheter <NUM> which is introduced from the jugular vein and advanced along a superior vena cava (SVC) approach to the GCV, and a left atrial (LA) catheter <NUM>, which is introduced at the femoral vein and introduced along an inferior vena cava (IVC) approach, across the inter-atrial septum and into the left atrium. Each catheter includes a magnetic head along a distal portion thereof (magnetic head <NUM> of catheter <NUM> and magnetic head <NUM> of catheter <NUM>) such that when magnetically coupled, the catheters provide a stable region to facilitate penetration of a tissue wall between the LA and GCV and subsequent advancement of the puncturing guidewire <NUM> through the GCV catheter <NUM> and into the LA catheter <NUM>. Notably, a trailing end of the puncturing guidewire <NUM> is attached to one end of a bridging element <NUM> (e.g. suture), the other end of which is attached to posterior anchor <NUM> disposed on the distal portion of GCV catheter <NUM>. Such a configuration allows the bridging element <NUM> to be advanced across the left atrium by advancing the puncturing guidewire <NUM> through the LA catheter <NUM> to exit from the femoral vein, while the magnetic heads remain magnetically coupled to each other, as shown in <FIG>. As can be understood by referring to <FIG>, the penetrating guidewire <NUM> has a length greater than the combined length of the catheters such that the guidewire <NUM> can be manually advanced externally from one vascular access point until the guidewire <NUM> exits the other vascular access point due to the stiffness of the guidewire <NUM>. The guidewire <NUM> can be further retracted after exiting so as to pull the attached bridging element through the vascular path until the bridging element also exits the same vascular access point. Performing this process while the GCV catheter <NUM> and LA catheter <NUM> are magnetically coupled provides improved stability during the process and, more importantly, covers the puncturing guidewire <NUM> and bridging element <NUM> while being pulled across the delicate tissues of the heart. The benefits of such a configuration, as compared to conventional delivery approaches, include improved safety for the patient, single operator deployment, significantly reduced duration of the deployment procedure and reduced delivery device lengths and cost of goods. The advantages of such an approach in deploying the implant can be understood further by referred to the following figures, which describe the implant and associated components in more detail as well as conventional approaches of delivery and deploying such implants.

<FIG> show embodiments of an implant <NUM> that is sized and configured to extend across the left atrium in generally an anterior-to-posterior direction, spanning the mitral valve annulus. The implant <NUM> comprises a spanning region or bridging element <NUM> having a posterior anchor region <NUM> and an anterior anchor region <NUM>.

The posterior anchor region <NUM> is sized and configured to allow the bridging element <NUM> to be placed in a region of atrial tissue above the posterior mitral valve annulus. This region is preferred, because it generally presents more tissue mass for obtaining purchase of the posterior anchor region <NUM> than in a tissue region at or adjacent to the posterior mitral annulus. Engagement of tissue at this supra-annular location also may reduce risk of injury to the circumflex coronary artery. In a small percentage of cases, the circumflex coronary artery may pass over and medial to the great cardiac vein on the left atrial aspect of the great cardiac vein, coming to lie between the great cardiac vein and endocardium of the left atrium. However, since the forces in the posterior anchor region are directed upward and inward relative to the left atrium and not in a constricting manner along the long axis of the great cardiac vein, the likelihood of circumflex artery compression is less compared to other technologies in this field that do constrict the tissue of the great cardiac vein. Nevertheless, should a coronary angiography reveal circumflex artery stenosis, the symmetrically shaped posterior anchor may be replaced by an asymmetrically shaped anchor, such as where one limb of a T-shaped member is shorter than the other, thus avoiding compression of the crossing point of the circumflex artery. The asymmetric form may also be selected first based on a pre-placement angiogram.

An asymmetric posterior anchor may be utilized for other reasons as well. The asymmetric posterior anchor may be selected where a patient is found to have a severely stenotic distal great cardiac vein, where the asymmetric anchor better serves to avoid obstruction of that vessel. In addition, an asymmetric anchor may be chosen for its use in selecting application of forces differentially and preferentially on different points along the posterior mitral annulus to optimize treatment, i.e., in cases of malformed or asymmetrical mitral valves.

The anterior anchor region <NUM> is sized and configured to allow the bridging element <NUM> to be placed, upon passing into the right atrium through the septum, adjacent tissue in or near the right atrium. For example, as is shown in <FIG>, the anterior anchor region <NUM> may be adjacent or abutting a region of fibrous tissue in the interatrial septum. As shown, the anchor site <NUM> is desirably superior to the anterior mitral annulus at about the same elevation or higher than the elevation of the posterior anchor region <NUM>. In the illustrated embodiment, the anterior anchor region <NUM> is adjacent to or near the inferior rim of the fossa ovalis. Alternatively, the anterior anchor region <NUM> can be located at a more superior position in the septum, e.g., at or near the superior rim of the fossa ovalis. The anterior anchor region <NUM> can also be located in a more superior or inferior position in the septum, away from the fossa ovalis, provided that the anchor site does not harm the tissue in the region.

Alternatively, the anterior anchor region <NUM>, upon passing through the septum into the right atrium, may be positioned within or otherwise extend to one or more additional anchors situated in surrounding tissues or along surrounding areas, such as within the superior vena cava (SVC) or the inferior vena cava (IVC).

In use, the spanning region or bridging element <NUM> can be placed into tension between the two anchor regions <NUM> and <NUM>. The implant <NUM> thereby serves to apply a direct mechanical force generally in a posterior to anterior direction across the left atrium. The direct mechanical force can serve to shorten the minor axis (along line P-A in <FIG>) of the annulus. In doing so, the implant <NUM> can also reactively reshape the annulus along its major axis (line CM-CL in <FIG>) and/or reactively reshape other surrounding anatomic structures. It should be appreciated, however, the presence of the implant <NUM> can serve to stabilize tissue adjacent the heart valve annulus, without affecting the length of the minor or major axes.

It should also be appreciated that, when situated in other valve structures, the axes affected may not be the "major" and "minor" axes, due to the surrounding anatomy. In addition, in order to be therapeutic, the implant <NUM> may only need to reshape the annulus during a portion of the heart cycle, such as during late diastole and early systole when the heart is most full of blood at the onset of ventricular systolic contraction, when most of the mitral valve leakage occurs. For example, the implant <NUM> may be sized to restrict outward displacement of the annulus during late ventricular diastolic relaxation as the annulus dilates.

The mechanical force applied by the implant <NUM> across the left atrium can restore to the heart valve annulus and leaflets a more normal anatomic shape and tension. The more normal anatomic shape and tension are conducive to coaptation of the leaflets during late ventricular diastole and early ventricular systole, which, in turn, reduces mitral regurgitation.

In its most basic form, the implant <NUM> is made from a biocompatible metallic or polymer material, or a metallic or polymer material that is suitably coated, impregnated, or otherwise treated with a material to impart biocompatibility, or a combination of such materials. The material is also desirably radio-opaque or incorporates radio-opaque features to facilitate fluoroscopic visualization.

In some embodiments, the implant <NUM>, or at least a portion thereof, can be formed by bending, shaping, joining, machining, molding, or extrusion of a metallic or polymer wire form structure, which can have flexible or rigid, or inelastic or elastic mechanical properties, or combinations thereof. In other embodiments, the implant <NUM>, or at least a portion thereof, can be formed from metallic or polymer thread-like or suture material. Materials from which the implant <NUM> can be formed include, but are not limited to, stainless steel, Nitinol, titanium, silicone, plated metals, Elgiloy™, NP55, and NP57.

In any of the implants described herein, the bridging member can be formed of a substantially inelastic material, such as a thread-like or suture material.

The posterior anchor region <NUM> is sized and configured to be located within or at the left atrium at a supra-annular position, i.e., positioned within or near the left atrium wall above the posterior mitral annulus.

In the illustrated embodiment, the posterior anchor region <NUM> is shown to be located generally at the level of the great cardiac vein, which travels adjacent to and parallel to the majority of the posterior mitral valve annulus. This extension of the coronary sinus can provide a strong and reliable fluoroscopic landmark when a radio-opaque device is placed within it or contrast dye is injected into it. As previously described, securing the bridging element <NUM> at this supra-annular location also lessens the risk of encroachment of and risk of injury to the circumflex coronary artery compared to procedures applied to the mitral annulus directly. Furthermore, the supra-annular position assures no contact with the valve leaflets therefore allowing for coaptation and reduces the risk of mechanical damage.

The great cardiac vein also provides a site where relatively thin, non-fibrous atrial tissue can be readily augmented and consolidated. To enhance hold or purchase of the posterior anchor region <NUM> in what is essentially non-fibrous heart tissue, and to improve distribution of the forces applied by the implant <NUM>, the posterior anchor region <NUM> may include a posterior anchor <NUM> placed within the great cardiac vein and abutting venous tissue. This makes possible the securing of the posterior anchor region <NUM> in a non-fibrous portion of the heart in a manner that can nevertheless sustain appreciable hold or purchase on that tissue for a substantial period of time, without dehiscence, expressed in a clinically relevant timeframe.

The anterior anchor region is sized and configured to allow the bridging element <NUM> to remain firmly in position adjacent or near the fibrous tissue and the surrounding tissues in the right atrium side of the atrial septum. The fibrous tissue in this region provides superior mechanical strength and integrity compared with muscle and can better resist a device pulling through. The septum is the most fibrous tissue structure in its own extent in the heart. Surgically handled, it is usually one of the only heart tissues into which sutures actually can be placed and can be expected to hold without pledgets or deep grasps into muscle tissue, where the latter are required.

As shown in <FIG>, the anterior anchor region <NUM> passes through the septal wall at a supra-annular location above the plane of the anterior mitral valve annulus. The supra-annular distance on the anterior side can be generally at or above the supra-annular distance on the posterior side. The anterior anchor region <NUM> is shown at or near the inferior rim of the fossa ovalis, although other more inferior or more superior sites can be used within or outside the fossa ovalis, taking into account the need to prevent harm to the septal tissue and surrounding structures.

By locating the bridging element <NUM> at this supra-annular level within the right atrium, which is fully outside the left atrium and spaced well above the anterior mitral annulus, the implant <NUM> avoids the impracticalities of endovascular attachment at or adjacent to the anterior mitral annulus, where there is just a very thin rim of annulus tissue that is bounded anteriorly by the anterior leaflet, inferiorly by the aortic outflow tract, and medially by the atrioventricular node of the conduction system. The anterior mitral annulus is where the non-coronary leaflet of the aortic valve attaches to the mitral annulus through the central fibrous body. Anterior location of the implant <NUM> in the supra-annular level within the right atrium (either in the septum or in a vena cava) avoids encroachment of and risk of injury to both the aortic valve and the AV node.

The purchase of the anterior anchor region <NUM> in fibrous septal tissue is desirably enhanced by a septal member <NUM> or an anterior anchor <NUM>, or a combination of both. <FIG> show the anterior anchor region including a septal member <NUM>. 10C The septal member <NUM> may be an expandable device and also may be a commercially available device such as a septal occluder, e.g., Amplatzer® PFO Occluder (see <FIG>). The septal member <NUM> preferably mechanically amplifies the hold or purchase of the anterior anchor region <NUM> in the fibrous tissue site. The septal member <NUM> also desirably increases reliance, at least partly, on neighboring anatomic structures of the septum to make firm the position of the implant <NUM>. In addition, the septal member <NUM> may also serve to plug or occlude the small aperture that was created in the fossa ovalis or surrounding area during the implantation procedure.

Anticipating that pinpoint pulling forces will be applied by the anterior anchor region <NUM> to the septum, the forces acting on the septal member <NUM> should be spread over a moderate area, without causing impingement on valve, vessels or conduction tissues. With the pulling or tensioning forces being transmitted down to the annulus, shortening of the minor axis is achieved. A flexurally stiff septal member is preferred because it will tend to cause less focal narrowing in the direction of bridge element tension of the left atrium as tension on the bridging element is increased. The septal member <NUM> should also have a low profile configuration and highly washable surfaces to diminish thrombus formation for devices deployed inside the heart. The septal member may also have a collapsed configuration and a deployed configuration. The septal member <NUM> may also include a hub <NUM> (see <FIG>) to allow attachment of the anchor <NUM>. A septal brace may also be used in combination with the septal member <NUM> and anterior anchor <NUM> to distribute forces uniformly along the septum. Alternatively, devices in the IVC or the SVC can be used as anchor sites, instead of confined to the septum.

Location of the posterior and anterior anchor regions <NUM> and <NUM> having radio-opaque bridge locks and well demarcated fluoroscopic landmarks respectively at the supra-annular tissue sites just described, not only provides freedom from key vital structure damage or local impingement -- e.g., to the circumflex artery, AV node, and the left coronary and non-coronary cusps of the aortic valve - but the supra-annular focused sites are also not reliant on purchase between tissue and direct tension-loaded penetrating / biting / holding tissue attachment mechanisms. Instead, physical structures and force distribution mechanisms such as stents, T-shaped members, and septal members can be used, which better accommodate the attachment or abutment of mechanical levers and bridge locks, and through which potential tissue tearing forces can be better distributed. Further, the anchor sites <NUM>, <NUM> do not require the operator to use complex imaging. Adjustment of implant position after or during implantation is also facilitated, free of these constraints. The anchor sites <NUM>, <NUM> also make possible full intra-atrial retrieval of the implant <NUM> by endovascularly snaring and then cutting the bridging element <NUM> at either side of the left atrial wall, from which it emerges.

In the embodiments shown in <FIG>, the implant <NUM> is shown to span the left atrium beginning at a posterior point of focus superior to the approximate mid-point of the mitral valve annulus, and proceeding in an anterior direction in a generally straight path directly to the region of anterior focus in the septum. The spanning region or bridging element <NUM> of the implant <NUM> may be preformed or otherwise configured to extend in this essentially straight path above the plane of the valve, without significant deviation in elevation toward or away from the plane of the annulus, other than as dictated by any difference in elevation between the posterior and anterior regions of placement. It is appreciated that such implants can include bridging member with lateral or medial deviations and/or superior or inferior deviations and can include bridging members that are rigid or semi-rigid and/or substantially fixed in length.

It is to be appreciated that an anchor as described herein, including a posterior or anterior anchor, describes an apparatus that may releasibly hold the bridging element <NUM> in a tensioned state. As can be seen in <FIG>, anchors <NUM> and <NUM> respectively are shown releasibly secured to the bridging element <NUM>, allowing the anchor structure to move back and forth independent of the inter-atrial septum and inner wall of the great cardiac vein during a portion of the cardiac cycle when the tension force may be reduced or becomes zero. Alternative embodiments are also described, all of which may provide this function. It is also to be appreciated that the general descriptions of posterior and anterior anchors are nonlimiting to the anchor function, i.e., a posterior anchor may be used anterior, and an anterior anchor may be used posterior.

When the bridging element is in an abutting relationship to a septal member (e.g. anterior anchor) or a T-shaped member (e.g. posterior anchor), for example, the anchor allows the bridging element to move freely within or around the septal member or T-shaped member, i.e., the bridging element is not connected to the septal member or T-shaped member. In this configuration, the bridging element is held in tension by the locking bridge stop, whereby the septal member or T-shaped member serves to distribute the force applied by the bridging element across a larger surface area. Alternatively, the anchor may be mechanically connected to the septal member or T-shaped member, e.g., when the bridge stop is positioned over and secured to the septal member hub. In this configuration, the bridging element is fixed relative to the septal member position and is not free to move about the septal member.

<FIG> show perspectives views of an example locking bridge stop <NUM> in accordance with the present invention. Each bridge stop <NUM> preferably includes a fixed upper body <NUM> and a movable lower body <NUM>. Alternatively, the upper body <NUM> may be movable and the lower body <NUM> may be fixed. The upper body <NUM> and lower body <NUM> are positioned circumjacent a tubular shaped rivet <NUM>. The upper body <NUM> and lower body <NUM> are preferably held in position by the rivet head <NUM> and a base plate <NUM>. The rivet <NUM> and base plate <NUM> includes a predetermined inner diameter <NUM>, sized so as to allow the bridge stop <NUM> to be installed over a guide wire. A spring, such as a spring washer <NUM>, or also known in the mechanical art as a Belleville Spring, is positioned circumjacent the rivet <NUM> and between the rivet head <NUM> and the upper body <NUM>, and applies an upward force on the lower body <NUM>. The lower body <NUM> is movable between a bridge unlocked position (see <FIG>), and a bridge locked position (see <FIG>). In the bridge unlocked position, the lower body <NUM> and the upper body <NUM> are not in contacting communication, creating a groove <NUM> between the upper body <NUM> and lower body <NUM>. In the bridge locked position, the axial force of the spring washer <NUM> urges the lower body <NUM> into contacting, or near contacting communication with the upper body <NUM>, whereby the bridging element <NUM>, which has been positioned within the groove <NUM>, is locked in place by the axial force of the lower body <NUM> being applied to the upper body <NUM>. In use, the bridging element <NUM> is positioned within the groove <NUM> while the lower body <NUM> is maintained in the bridge unlocked position <NUM>. The bridge stop <NUM> is positioned against the septal member <NUM> and the bridging element <NUM> is adjusted to proper tension. The lower body <NUM> is then allowed to move toward the upper body <NUM>, thereby fixing the position of the bridge stop <NUM> on the bridging element <NUM>. While this example depicts a particular locking bridge stop design, it is appreciated that any suitable lock could be used, including any of the types described in <CIT>.

<FIG> show alternative heart implants suitable for delivery with the methods and delivery systems described herein. <FIG> shows an implant <NUM>' having a T-shaped posterior anchor <NUM> in the great cardiac vein and T-shaped anterior anchor <NUM>. The anterior T-shaped bridge stop <NUM> may be of a construction of any of the T-shaped bridge stop embodiments described. The T-shaped member <NUM> includes a lumen <NUM> extending through the T-shaped member <NUM> perpendicular to the length of the T-shaped member. The bridging element <NUM> may be secured by a free floating bridge stop as previously described. <FIG> shows an implant <NUM>" having a T-shaped posterior anchor <NUM> in the great cardiac vein and a lattice style anterior anchor <NUM>. The lattice <NUM> is positioned on the septal wall at or near the fossa ovalis. Optionally, the lattice <NUM> may include a reinforcement strut <NUM> to distribute the bridging element <NUM> tension forces over a greater area on the septal wall. The anterior lattice style bridge stop <NUM> may be packed in a deployment catheter with the bridging element <NUM> passing through its center. The lattice <NUM> is preferably self-expanding and may be deployed by a plunger. The bridging element <NUM> may be secured by a free floating bridge stop as previously described. It is appreciated that various other such implants could be devised that utilized the same concepts as in the above described implants for delivery and deployment with the systems and methods described herein.

<FIG> show alternative methods of connecting the bridging element <NUM> to a T-shaped posterior anchor. <FIG> shows a T-shaped member <NUM> where the bridging element <NUM> is wound around a central portion of the T-shaped member. The bridging element <NUM> may be secured by adhesive <NUM>, knot, or a securing band placed over the bridging element <NUM>, for example. Alternatively, the bridging element <NUM> may first be threaded through a lumen <NUM> extending through the T-shaped posterior anchor <NUM> perpendicular the length of the T-shaped member. The bridging element <NUM> may then be wound around the T-shaped member, and secured by adhesive <NUM>, securing band, or knot, for example. <FIG> shows a T-shaped member <NUM> where the bridging element <NUM> is welded or forged to a plate <NUM>. The plate <NUM> may then be embedded within the T-shaped member <NUM>, or alternatively, secured to the T-shaped member <NUM> by gluing or welding, for example. It is appreciated that various other couplings could be used to secure the bridging element <NUM> and posterior anchor <NUM> and facilitate delivery with the systems and methods described herein.

<FIG> depict alternative anchors suitable for use as posterior anchors within a heart implant in accordance with the invention. <FIG> is a perspective view of a T-shaped anchor <NUM>' that includes an intravascular stent <NUM> and, optionally, a reinforcing strut <NUM>. The stent <NUM> may be a balloon expandable or self-expanding stent. As previously described, the T-shaped anchor <NUM>' is preferably connected to a predetermined length of the bridging element <NUM>. The bridging element <NUM> may be held within, on, or around the T-shaped bridge stop <NUM> through the use of any of the bridge locks as previously described, or may be connected to the T-shaped anchor <NUM> by way of tying, welding, or gluing, for example, or any combination. <FIG> depicts a T-shaped anchor <NUM>" that includes a flexible tube <NUM> having a predetermined length, e.g., three to eight centimeters, and an inner diameter <NUM> sized to allow at least a guide wire to pass through. The tube <NUM> is preferably braided, but may be solid as well, and may also be coated with a polymer material. Each end of the tube <NUM> preferably includes a radio-opaque marker <NUM> to aid in locating and positioning the T-shaped anchor. The tube <NUM> also preferably includes atraumatic ends to protect the vessel walls. The tube may be flexurally curved or preshaped so as to generally conform to the curved shape of the great cardiac vein or interatrial septum and be less traumatic to surrounding tissue. A reinforcing center tube <NUM> may also be included to add stiffness to the anchor and aids in preventing egress of the anchor from the great cardiac vein and left atrium wall. The bridging element <NUM> extends through a central hole <NUM> in an interior side of the reinforcing center tube <NUM>. Each of the anchors described can be straight or curvilinear in shape, or flexile so as to accommodate an anatomy. It is appreciated that various other type of anchors could be used a posterior anchor <NUM> attached to bridging element <NUM> for delivery and deployment with the systems and methods described herein.

The implants systems <NUM> described herein lend themselves to implantation in a heart valve annulus in various ways. Preferably, the implants <NUM> are implanted using catheter-based technology via a peripheral venous access site, such as in the femoral or jugular vein (via the IVC or SVC) under image guidance, or trans-arterial retrograde approaches to the left atrium through the aorta from the femoral artery also under image guidance. As previously described, the implants <NUM> comprise independent components that are assembled within the body to form an implant, and delivered and assembled from an exterior the body through interaction of multiple catheters.

<FIG> show deployment of an implant <NUM> of the type shown in <FIG> by a percutaneous, catheter-based procedure, under image guidance using conventional methods into the femoral or jugular vein, or typically, a combination of both, such as any of those described in <CIT>.

Percutaneous vascular access is achieved by conventional methods into the femoral or jugular vein, or typically, a combination of both. As shown in <FIG>, under image guidance, a first catheter, or GCV catheter <NUM>, is advanced into the great cardiac vein from a superior vena cava (SVC) route accessed from a neck vein (e.g. jugular vein) along a GCV guidewire <NUM>. As shown in <FIG>, the LA catheter <NUM> is advanced from the right atrium via an inferior vena cava (IVC) accessed from a femoral vein, through the septum, typically at or near the fossa ovalis, and into the left atrium. The septal wall at the fossa ovalis is punctured with a trans-septal needle and a LA guide wire <NUM> is advanced through the septum into the left atrium. Typically a large bore (<NUM>-<NUM> French) hemostasis sheath with a "Mullins" shape is placed in the LA to act as a conduit for placement for subsequent devices to placed or removed from the LA without injuring the tissues along the pathway to or in the LA. The LA catheter <NUM> is then advanced into the left atrium athrough this sheath.

Each of catheters <NUM>, <NUM> include a magnetic head <NUM>, <NUM>, respectively, disposed along a distal portion thereof, the magnetic heads being configured to facilitate magnetic coupling when positioned at a desired orientation and position across a tissue wall between the left atrium and the great cardiac vein. As shown in <FIG>, LA catheter <NUM> includes distal magnetic head having a N-S magnetic poles arranged axially along the catheter, while the GCV catheter <NUM> includes distal magnetic head having N-S magnetic poles arranged laterally relative a longitudinal axis of the catheter. This arrangement facilitate a transverse or perpendicular magnetic coupling between the respective catheters, as shown in <FIG> so as to allow passage of a penetrating element or guidewire, typically from a channel within one magnetic head into a corresponding channel of the other magnetic head. In this approach, the penetrating element is a puncturing guidewire <NUM> with a sharpened distal end. Typically, the puncturing guidewire <NUM> is advanced through a curved channel <NUM> within the magnetic head <NUM> of the GCV catheter <NUM> and enters a funnel-shaped channel <NUM> of magnetic head <NUM> of LA catheter <NUM>. While in this embodiment, the magnetic head of GCV catheter <NUM> has a single magnet, it is appreciated that various other embodiments can include a magnetic head having additional magnets oriented to facilitate a desired alignment, for example, a three-magnet head in which a center magnet has magnetic poles oriented laterally to an axis of the catheter between two magnets with poles oriented axially, such as that shown in <CIT>.

Next, as shown in <FIG>, the penetrating guidewire is advanced through the LA catheter <NUM> until it exits the femoral artery access point at the groin. The left atrium magnetic catheter A is then replaced by a very long exchange catheter <NUM>, which is carefully pushed across the puncture site along the great cardiac vein to interface with the great cardiac vein magnetic catheter <NUM>. The exchange catheter <NUM> is pushed simultaneously with removing the great cardiac vein magnetic catheter <NUM> to avoid exposing the puncturing wire to tissue. Exposure of the puncturing wire during this process could easily slice through tissue should the wire move or become tensioned during removal or replacement of one of the catheters. This process typically requires two operators, one operator pushes the exchange catheter while the other operator simultaneously removes the great cardiac vein magnetic catheter, often while utilizing visualization techniques to ensure the two catheters remain interfaced and the puncturing wire remains covered. Once the exchange catheter <NUM> is placed from neck to groin, the puncturing wire is removed and replaced with a left atrial extension guidewire <NUM>, as shown in <FIG>.

Next, extension guide wire <NUM> is gently retracted, causing the bridging element <NUM> to follow through the vasculature structure. If the optional exchange catheter <NUM> is used (as shown in <FIG>), the extension guide wire <NUM> retracts through the lumen of the exchange catheter <NUM> without injuring tissues. The extension guide wire <NUM> is completely removed from the body at the femoral vein, leaving the bridging element <NUM> extending from exterior the body (preferably at the femoral sheath), through the vasculature structure, and again exiting at the superior vena cava sheath. The extension guide wire <NUM> may then be removed from the bridging element <NUM> by cutting or detaching the bridging element <NUM> at or near the interface coupling <NUM> between the bridging element <NUM> and extension guide wire <NUM>. The anterior end of the extension guidewire <NUM> is attached to one end of the bridging element (e.g. suture material) while the other end of the bridging element is attached to the posterior anchor, which is retained within a posterior anchor delivery catheter <NUM>. As can be seen in <FIG>, the extension guide wire <NUM> is gently retracted, causing the bridging element <NUM> to follow into the exchange catheter <NUM> and through the vasculature structure.

Posterior anchor <NUM> disposed within deployment catheter <NUM> is connected to the trailing end of bridging element <NUM> extending from the superior vena cava. While a T-shaped anchor is shown here, it is appreciated that various other types of posterior anchors can be used (e.g. stent, half-stent, etc.). The deployment catheter <NUM> is then positioned onto or over the GCV guide wire <NUM> and abutted against exchange catheter <NUM>. The two-operator pushing and pulling process is repeated pushing the posterior anchor delivery catheter <NUM> while simultaneously removing the exchange catheter <NUM> so as to position the posterior anchor within the great cardiac vein and the bridging element extends across the left atrium. Optionally, the bridging element <NUM> may be pulled from the femoral vein region, either individually, or in combination with the deployment catheter <NUM>, to facilitate advancement of the posterior anchor <NUM> and bridging element into position in the great cardiac vein and across the left atrium. The GCV guide wire <NUM> is then retracted letting the T-shaped anchor <NUM> separate from the GCV guide wire <NUM> and deployment catheter <NUM>. Preferably under image guidance, and once separation is confirmed, the bridging element <NUM> is gently pulled to position the T-shaped anchor <NUM> in abutment against the venous tissue within the great cardiac vein and centered over the GCV access lumen <NUM>. The deployment catheter <NUM> and exchange catheter <NUM> may then be removed. The T-shaped anchor <NUM> with attached bridging element <NUM> remain within the great cardiac vein. The length of bridging element <NUM> extends from the posterior T-shaped anchor <NUM>, through the left atrium, through the fossa ovalis, through the vasculature, and preferably remains accessible exterior the body. The bridging element <NUM> is now ready for the next step of establishing the anterior anchor region <NUM>, as previously described and as shown in <FIG>.

Once the posterior anchor region <NUM>, bridging element <NUM>, and anterior anchor region <NUM> configured as previously described, a tension is placed on the bridging element <NUM>. The implant <NUM> and associated regions may be allowed to settle for a predetermined amount of time, e.g., five or more seconds. The mitral valve and mitral valve regurgitation are observed for desired therapeutic effects. The tension on the bridging element <NUM> may be adjusted until a desired result is achieved. The anchor <NUM> is then secured the bridging element <NUM> by use of a locking bridge stop <NUM> when the desired tension or measured length or degree of mitral regurgitation reduction is achieved.

In one aspect, an improved anchor delivery catheter allows for delivery and deployment of the above-described implant with fewer catheters and improved ease of use as compared to the conventional approach described above. In some embodiments, the catheter systems includes an anchor delivery catheter having a distal magnet portion that facilitates access to a heart chamber from within an adjacent vasculature by passage of a penetrating guidewire to a magnetically couple catheters within the heart chamber. In some embodiments, the anchor delivery catheter is configured for delivery of the bridging element across the heart chamber (e.g. left atrium), once access is achieved, and subsequent deployment of the anchor within the vasculature (e.g. great cardiac vein). In some embodiments, the bridging element is attached to a trailing end of the penetrating guidewire while the other end is attached to the posterior anchor disposed on a distal portion of the delivery catheter. This allows the bridging element to be advanced through the penetration between the heart chamber and vasculature by continued advancement of the penetrating guidewire from one vascular access point (e.g. jugular vein) to exit the body at the second vascular access point (e.g. femoral vein).

In some embodiments, for example as shown in <FIG>, the above described anchor delivery is a GCV catheter <NUM> for delivery of the posterior anchor <NUM> within the GCV. Catheter <NUM> preferably includes a magnetic or ferromagnetic head <NUM> positioned along a distal portion of the catheter shaft. Optionally, a hub can be positioned on the proximal end. The catheter shaft may include a proximal section that is generally stiff to allow for torquability of the shaft, which can be of a solid or braided construction. The proximal section includes a predetermined length (e.g., fifty centimeters or more), to allow positioning of the shaft within the vasculature structure. A distal section, along which the distal portion is defined, may be generally flexible to allow for steerability within the vasculature, e.g., within the chamber or vasculature of the heart. The distal section can also be of a predetermined length (e.g., ten centimeters or more) suitable for maneuvering within the heart. An inner diameter or lumen of the catheter shaft is preferably sized to allow passage of a GCV guide wire <NUM>, and a penetrating guide wire as well as a bridging element. The GCV catheter <NUM> preferably includes a radio-opaque marker to facilitate adjusting the catheter under image guidance to align with the LA catheter <NUM>. The magnetic or ferromagnetic head <NUM> is preferably polarized to magnetically attract or couple the distal end of the LA catheter <NUM>, as described previously. Magnetic head <NUM> includes a guide channel formed therein to facilitate passage of the penetrating guidewire through the channel and into a corresponding channel in the magnetic head of the LA catheter <NUM>.

Similar to the GCV catheter 50the LA catheter <NUM> preferably includes a magnetic or ferromagnetic head <NUM> positioned on a distal end thereof. The catheter shaft may include a proximal and distal sections similar to those of catheter <NUM> described above. The proximal section may be generally stiff to allow for torquability of the shaft, and may be of a solid or braided construction. The distal section includes a predetermined length, e.g., ninety centimeters, to allow positioning of the shaft within the vasculature structure. The distal section may be generally flexible and anatomically shaped to allow for steerability through the fossa ovalis and into the left atrium. The distal section may also include a predetermined length, e.g., ten centimeters. An inner diameter or lumen of the catheter shaft is preferably sized to allow passage of an LA guide wire <NUM>, and additionally may accept the penetrating guide wire <NUM> passed from the GCV and subsequently the bridging element <NUM> attached thereto. The LA catheter <NUM> may also include a radio-opaque marker to facilitate adjusting the catheter <NUM> under image guidance to align with the GCV catheter <NUM>. The magnetic or ferromagnetic head <NUM> of the LA catheter <NUM> is polarized to magnetically attract or couple the distal end of the GCV catheter, for example, as shown in <FIG>. It is appreciated that the magnetic forces in the head <NUM> may be reversed, as long as attracting magnetic poles in the LA catheter <NUM> and the GCV catheter <NUM> are aligned.

While a particular configuration of magnetic heads are described above, it is appreciated that various other magnetic head configurations could be used, for example of those any of these described in <CIT>. Detailed examples of such catheter configuration are described further in <FIG>.

Access to the vascular system is commonly provided through the use of introducers known in the art. A 16F or less hemostasis introducer sheath (not shown), for example, may be first positioned in the superior vena cava (SVC), providing access for the GCV catheter <NUM>. Alternatively, the introducer may be positioned in the subclavian vein. A second 14F or less introducer sheath (not shown and described above) may then be positioned in the right femoral vein, providing access for the LA catheter <NUM>. Access at both the SVC and the right femoral vein, for example, also allows the implantation methods to utilize a loop guide wire. For instance, in a procedure to be described later, a loop guide wire is generated by advancing a LA guide wire through the vasculature until it exits the body and extends external the body at both the superior vena cava sheath and femoral sheath. The LA guide wire may follow an intravascular path that extends at least from the superior vena cava sheath through the interatrial septum into the left atrium and from the left atrium through atrial tissue and through a great cardiac vein to the femoral sheath.

<FIG> illustrate a method of implantation utilizing a magnetic anchor delivery catheter in accordance with aspects of the invention. <FIG> depict positioning of the GCV anchor delivery catheter <NUM> within the great cardiac vein adjacent a posterior annulus of the mitral valve. First, as shown in <FIG>, under image guidance, the GCV guide wire <NUM> (e.g. a <NUM> (<NUM> inch) guidewire) for example, is advanced into the coronary sinus to the great cardiac vein along an SVC approach. Optionally, an injection of contrast with an angiographic catheter may be made into the left main artery from the aorta and an image taken of the left coronary system to evaluate the position of vital coronary arterial structures. An injection of contrast may also be made in the great cardiac vein in order to provide an image and a measurement. If the great cardiac vein is too small, the great cardiac vein may be dilated with a <NUM> to <NUM> millimeter balloon, for example, to midway the posterior leaflet.

As shown in <FIG>, the GCV catheter <NUM> is advanced over the GCV guide wire <NUM> so that the distal magnetic head <NUM> and posterior anchor <NUM> are positioned at or near a desired location in the great cardiac vein, for example near the center of the posterior leaflet or posterior mitral valve annulus. The desired position for the GCV catheter <NUM> may also be viewed as approximately <NUM> to <NUM> centimeters from the anterior intraventricular vein takeoff. Once the GCV catheter <NUM> is positioned, an injection may be made to confirm sufficient blood flow around the GCV catheter <NUM>. If blood flow is low or non-existent, the GCV catheter <NUM> may be pulled back into the coronary sinus until needed.

As shown in <FIG>, the LA catheter <NUM> is then deployed in the left atrium. From the femoral vein, under image guidance, the LA guide wire <NUM>, a <NUM> (<NUM> inch) guidewire for example, is advanced into the right atrium. A 7F Mullins dilator with a trans-septal needle (not shown) can be deployed into the right atrium. An injection is made within the right atrium to locate the fossa ovalis on the septal wall. The septal wall at the fossa ovalis can be punctured with a trans-septal needle and the guide wire <NUM> is advanced into the left atrium. The trans-septal needle is then removed and the dilator is advanced into the left atrium. An injection is made to confirm position relative to the left ventricle. The Mullins system is removed and then replaced with a 12F or other appropriately sized Mullins system. The 12F Mullins system is positioned within the right atrium and extends a short distance into the left atrium and the LA catheter <NUM> is advanced into the left atrium. After advancement of the LA catheter <NUM> into the left atrium, a distal magnetic head <NUM> of the catheter is positioned in the region adjacent the great cardiac vein so as to magnetically couple with the magnetic head <NUM> of GCV magnetic catheter <NUM>, for example as shown in <FIG>. The magnetic heads automatically align the lumens of the LA catheter <NUM> and GCV catheter <NUM>.

As shown in <FIG>, once magnetically coupled, puncturing guidewire <NUM> is advanced through GCV catheter <NUM> to penetrate the tissue wall between the great cardiac vein and the left atrium and enters a lumen of the magnetic head <NUM> of LA catheter <NUM>. The operator continues to advance the puncturing guidewire <NUM> through a lumen of the LA catheter <NUM> until the guidewire exits the body (e.g. at the groin). Since the trailing end of the puncturing guidewire is attached to the one end of the bridging element <NUM> (e.g. suture), the other end of the bridging wire being attached to posterior anchor <NUM>, once the puncturing guidewire <NUM> exits the proximal end of the LA catheter <NUM>, the puncturing wire <NUM> can be pulled proximally from the LA catheter <NUM> thereby pulling the bridging element <NUM> through the GVC catheter <NUM>, across the left atrium within the LA catheter <NUM> and through the vasculature to exit the body at the groin, all while the LA catheter <NUM> and the GVC catheter <NUM> remain magnetically coupled. This approach ensures the puncturing wire <NUM> and the bridging element <NUM> remain covered while the being drawn through the vasculature over the delicate tissues of the heart. This avoids cutting or slicing the tissue with the bridging element when pulled across the tissues and further avoids the laborious pushing and pulling procedure and use of an exchange catheter described in the conventional approach.

As shown in <FIG>, the bridging element <NUM> extends from the posterior anchor <NUM> disposed within the distal portion of the GCV catheter <NUM>, spans the left atrium and extends through the LA catheter <NUM> and exits the body at the femoral vein. The operator can gently tug the bridging element <NUM> to remove any slack from the system and ensure it is properly positioned. In some embodiments, this action can also facilitate release of the posterior anchor <NUM> from the GCV delivery catheter <NUM>. The LA catheter <NUM> can be decoupled from the GCV catheter <NUM> and withdrawn while the bridging element remains in place, as shown in <FIG>. Optionally, the LA catheter <NUM> can remain within the left atrium extending through the septum until the posterior anchor <NUM> is fully deployed.

As shown in <FIG>, the GCV catheter <NUM> is adjusted, if needed, to position the posterior anchor <NUM> along the penetration for subsequent release from the catheter. The posterior anchor <NUM> can be released from the GCV delivery catheter <NUM> by proximally retracting the GCV guidewire <NUM> extending through the posterior anchor <NUM>. Optionally, the catheter configuration can include a releasable coupling feature, such as a tether <NUM>, that secures the posterior anchor <NUM> to the distal portion of GCV catheter <NUM> and extends from the proximally end so that an operator can proximally pull the tether to release the posterior anchor <NUM>. The tether can be defined as a wire or suture that frictionally engages the posterior anchor in place at one end and extends proximally from the catheter at the other end, or as a tether loop that wraps around the posterior anchor and interfaces with a feature along the distal portion of the GCV catheter and both ends extend proximally from the catheter such that pulling the tether releases. It is appreciated that various types of releasable couplings could be used including any of those described in <CIT> and <CIT>, incorporated herein by reference for all purposed. During the process, the GCV catheter <NUM> can be retracted slightly, particularly in embodiments where the posterior anchor <NUM> partly resides in a recessed portion of the magnetic head <NUM>. In many cases of complete or partial removal of the GCV catheter, the guidewire is left inside the GCV anchor to allow for retrieval until very end of the procedure. While in this embodiment, the posterior anchor <NUM> is an elongate member, such as a T-bar anchor, it is appreciated that various other deployment steps could be used to facilitate deployment of other types of posterior anchors. For example, when the posterior anchor <NUM> is a scaffold or stent-like structure, any suitable means of deploying such structures could be used. For example, a constraining sheath partly disposed over a self-expanding scaffold can be retracted thereby releasing the scaffold from the magnetic head portion <NUM> or a balloon expandable scaffold, or otherwise releasable scaffold can be used. Once the posterior anchor <NUM> is deployed, the GCV catheter <NUM> and GCV guidewire can be removed, as shown in <FIG>.

As shown in <FIG>, the posterior anchor <NUM> deployed within the great cardiac vein is attached to the bridging element <NUM> spanning the left atrium and extending through the vasculature along the IVC route to exit from the femoral vein at the groin. Since the bridging element <NUM> is not yet tensioned, there is little likelihood of cutting or damage to tissues at this point. Next, as shown in <FIG>, an anterior anchor delivery catheter <NUM> is advanced along the bridging element <NUM> with the anterior anchor mounted with the bridging element passing through its central hub the delivery catheter <NUM> having an anterior anchor <NUM>, collapsed inside the delivery sheath, disposed in a distal portion thereof, the bridging element passing through its central hub. The collapsed anterior anchor is guided to the FO or other suitable location along the septal wall and deployed, such as shown in <FIG>.

As shown in <FIG>, the anterior anchor <NUM> is deployed along the septal wall with a proximal locking bridge stop <NUM> through the delivery sheath. The length of the bridging element <NUM> can then be incrementally adjusted and held in place by the bridge lock <NUM> upon each adjustment until observation of the heart pumping indicates improved valve function. The excess bridging element <NUM> can then be cut with a cutting element of the catheter, or by use of a separate cutting catheter advanced along the bridging element <NUM>. The LA delivery catheter <NUM> can then be removed, leaving the fully deployed implant <NUM> in place within the heart, as shown in <FIG>.

As discussed previously, one purpose of some such delivery catheter configurations is to facilitate deployment of the posterior anchor while keeping the bridging element totally within the protection of the magnetically connected catheters by combining the magnets and keeping the posterior anchor on one delivery catheter in the great cardiac vein. Examples of such delivery catheter configurations are detailed below. It is appreciated that any of the aspects or features described in certain embodiments may be utilized in various other embodiments in accordance with the concepts described herein.

<FIG> show anchor delivery catheter configuration in accordance with aspects of the invention. In particular, the catheter configuration allows for magnetically coupling with a corresponding catheter to establish access within a heart chamber from adjacent vasculature and delivering a heart implant in accordance with aspect of the invention. These example delivery catheters are configured for use within a GCV catheter <NUM>, within the example delivery and deployment methods depicted above. It is appreciated that the following catheter configurations can include any of the various aspect described herein (e.g. length, materials, dimensions, etc.), but are not limited to the aspects described herein and could be configured as needed for a particular use or anatomy.

<FIG> shows a distal portion of a delivery catheter configuration <NUM> that includes a guidewire lumen 701a extending longitudinally to facilitate advancement of the catheter along a guidewire <NUM> positioned in the vasculature of the patient (e.g. within the great cardiac vein when the catheter configuration is utilized in a GVC anchor delivery catheter). The catheter can further include a puncture wire lumen 701b dimensioned to allow passage of the puncture wire and subsequent passage of the bridging element <NUM> attached thereto. The catheter includes a magnetic head <NUM> configured to magnetically couple with a magnetic head <NUM> of a corresponding catheter <NUM> through a tissue wall therebetween. Magnetic head <NUM> is defined so that the magnetic poles of the magnetic head are disposed laterally relative a longitudinal axis of the catheter so as to couple in a perpendicular orientation with magnetic head <NUM> of magnetic catheter <NUM>, in a similar fashion as in <FIG>. The magnetic head <NUM> further includes a guide channel <NUM> defined to steer puncturing guidewire <NUM> upward through an exit hole <NUM> on one side of the magnetic head <NUM> to direct the sharped distal tip <NUM> (e.g. flat tip) of the puncturing guidewire <NUM> through the tissue wall and into the magnetic head <NUM> of catheter <NUM>. The magnetic head <NUM> is defined with a central channel that is funnel-shaped so as to direct the puncturing wire <NUM> into the central channel. The dashed vertical line in <FIG> represents the point at which the delivery catheter extends outside the body. In any of these embodiments, the guidewire <NUM> and bridging element <NUM> and puncturing wire <NUM> can extend through a Y-arm connector to facilitate independent manual control of the guidewire <NUM> and the puncturing wire <NUM>/bridging element <NUM>. (The catheter shaft extending between the distal end portion and the Y-arm connector is not shown). In such embodiments, the length of the puncturing wire <NUM> is greater than the sum of both magnetic catheters, and the length of bridging element <NUM> is at least long enough to extend from the posterior anchor to the second access site, so that when the puncturing wire is pulled from the second access site it pulld the bridging element out the second access site. In some embodiments, the bridging element (suture) may be long enough that it remains outside the first access site until it is pulled out of the second access site. This may be desired in the unlikely event that the suture becomes disconnected from the pucturing wire before the suture is pulled out the second access site so that the operator may retrieve it by pulling on the proximal portion still out of the body. In this instance it would need to be as long as the sum of the length of the second catheter <NUM> and twice the length of the delivery catheter <NUM> since it needs to switch back as described above. It is appreciated that while the delivery catheter configuration is shown in <FIG> extending from right to left, the end portion of the catheter would extend from left to right when viewed from a front of the patient, such as shown in <FIG>.

Catheter <NUM> includes a catheter shaft <NUM> along its length, which can be formed of any suitable material, to facilitate advancement of the catheter through the vasculature. As shown, the magnetic head <NUM> is formed with a notch or contoured recess in one side, which in this embodiment is opposite the exit hole <NUM>, although could be located in any suitable location in embodiments. The notch, recess or groove <NUM> is configured to allow passage of the guidewire <NUM> and/or to receive at least a portion of posterior anchor <NUM>. In this embodiment, posterior anchor <NUM> is defined as an elongate member having a longitudinal lumen through which the guidewire <NUM> extends. It is appreciated that a posterior anchor having a longitudinal lumen through which the guidewire <NUM> extends could be utilized in any of the embodiments described herein. It is further appreciated that the posterior anchor <NUM> could be positioned partly extending within a recess of the magnetic head, extending distally of the magnetic head (as shown) or proximally, or could extend proximally and proximally and distally of the magnetic head (as shown in <FIG>) or could be disposed entirely proximal or entirely distal of the magnetic head (as shown in <FIG>).

An outer jacket <NUM> covers the magnetic head <NUM> and includes an opening over exit hole <NUM> to allow passage of the penetrating guidewire <NUM> therethrough. Typically, the outer jacket <NUM> is formed for a flexible polymer material and is defined to form a smooth interface with the catheter shaft <NUM>. The outer jackets helps maintain the magnetic head <NUM> within the catheter and may extend at least partly over the posterior anchor <NUM> to help retain the posterior anchor <NUM> during advancement of the catheter through the vasculature. Optionally, a polymeric rounded tip <NUM> can be provided on a distal end of the jacket to facilitate advancement of the catheter through the vasculature.

<FIG> shows a distal portion of a delivery catheter configuration <NUM> that includes a guidewire lumen <NUM> extending longitudinally to facilitate advancement of the catheter along a guidewire <NUM> positioned in the vasculature of the patient, within the great cardiac vein when the catheter configuration is utilized in a GVC anchor delivery catheter. The catheter can further include a puncture wire lumen 801b dimensioned to allow passage of the puncture wire <NUM> and subsequent passage of the bridging element <NUM> attached thereto. The catheter includes a magnetic head <NUM>, contained within inner jacket <NUM>, that is configured to magnetically couple with a magnetic head of another catheter on an opposite side of a tissue wall, as described in other embodiments. The magnetic head includes a guide channel (not shown) to direct the puncture guidewire <NUM> through exit hole <NUM> on one side of the magnetic head and into a lumen of the other catheter when magnetically coupled. The inner jacket <NUM> includes an opening over the exit hole <NUM> to allow passage of the distal sharpened end <NUM> (e.g. flat tip) of puncturing guidewire <NUM>. As shown, the posterior anchor <NUM> is defined as an expandable scaffold. Here, the expandable scaffold is self-expanding and constrained into the configuration shown by a constraining sheath <NUM> (shown as transparent for improved visibility of underlying components). Proximal retraction of the constraining sheath <NUM> allows the expandable scaffold posterior anchor <NUM> to expand and release from the inner jacket <NUM>. The bridging element <NUM> is attached to the proximal end of the puncturing guidewire <NUM> and extends back through the catheter, out through exit hole <NUM> outside of the inner jacket to a reinforcing rib <NUM> on the posterior anchor <NUM> such that once the bridging element <NUM> is passed through the exit hole and across the heart chamber and the posterior anchor <NUM> is deployed, catheter <NUM> can be withdrawn from within the deployed posterior anchor <NUM> and the implantation process can proceed with deployment of the anterior anchor, as described above. In some embodiments, deployment may further entail laterally collapsing the scaffold by pulling of bridging element <NUM>.

<FIG> shows a distal portion of a delivery catheter configuration <NUM> that includes a guidewire lumen 901a extending longitudinally to facilitate advancement of the catheter along a guidewire <NUM> positioned in the vasculature of the patient, within the great cardiac vein when the catheter configuration is utilized in a GVC anchor delivery catheter. The catheter can further include a puncture wire lumen 901b dimensioned to allow passage of the puncture wire <NUM> and the bridging member length extending to the preloaded posterior anchor, and in some embodiments the tether releasing wire. The catheter includes a magnetic head <NUM> (not shown) contained within an outer jacket <NUM>, the magnetic head being configured to magnetically couple with a magnetic head of another catheter, as described above. The magnetic head includes a guide channel (not shown) to direct the puncture guidewire <NUM> through an exit hole <NUM> and into a lumen of the other catheter when magnetically coupled. The outer jacket <NUM> includes an opening over the exit hole <NUM> to allow passage of the distal sharpened end <NUM> of puncturing guidewire <NUM> through exit hole <NUM>. As shown, the posterior anchor <NUM> is defined as a non-expandable scaffold. The scaffold can be secured in place by a releasable coupling, such as a suture or tether <NUM> that extends inside a lumen of the catheter to its proximal end, such that removal of the tether releases the scaffold. Release can be further facilitated by gently tugging the bridging element <NUM> advanced through the other magnetically coupled catheter. Catheter <NUM> can then be retracted and the implantation process can proceed with deployment of the anterior anchor, as described above. In some embodiments, deployment may further entail laterally collapsing the scaffold by pulling of the bridging element <NUM>.

<FIG> shows a distal portion of a delivery catheter configuration <NUM> having a magnetic head <NUM> and a posterior anchor <NUM> that is disposed over a guidewire <NUM> along which the catheter is advanced through the vasculature. In this embodiment, the posterior anchor <NUM> is mounted within a groove <NUM> defined within the magnetic head so as to be axially "stacked" and completely overlapping the magnetic head. The magnetic head includes with a side hole <NUM> through which the penetrating guidewire can be advanced and from which the bridging element <NUM> extends and attaches to the posterior anchor <NUM> at attachment feature <NUM>. The posterior anchor includes a central portion 1018a that is substantially rigid and that includes the attachment feature <NUM> and strain relief portions 1018b on each end that allow flexure so that the distal portion of the catheter can have some flexibility to accommodate curvature of the vasculature through which it is advanced. In this embodiment, the system includes a reinforced guidewire lumen <NUM> (e.g. braided or coiled wire lumen) to facilitate advancement of the posterior anchor and prevent kinking when advanced along a curved path. An outer jacket <NUM> extends over the magnetic head and includes an opening over the exit hole <NUM> and may include a distally tapered portion <NUM> having an opening through which the posterior anchor <NUM> can be deployed. Once the bridging element is delivered through a second catheter magnetically coupled to the delivery catheter, as described previously, the posterior anchor <NUM> can be released by withdrawing the guidewire <NUM> and guidewire lumen <NUM>, and can be further facilitated by gently tugging the bridging element <NUM> advanced through the other magnetically coupled catheter. In some embodiments, the posterior anchor <NUM> can be further secured by a releaseable coupling feature and released by retracting a tether, as previously described.

Previously described non-stenting "hypo-tube" posterior anchor deployment catheters, with an internal lumen dedicated to a guidewire, have relied on the bridge attachment location on the anchor to the to be aligned and mounted on the delivery catheter at or very near the exit hole of the puncturing wire in the magnet. One perceived advantage of such delivery catheter designs is that the anchor is at or immediately adjacent the puncture site at the time of the puncture and does not have to be repositioned before release from the catheter. One drawback associated with such designs is the larger profile, bulk and increased stiffness of the staked catheter elements in this distal section. Such designs where the posterior anchor is mounted within or partly within the magnetic portion of the delivery catheter, while suitable, may not always be ideal because the ability to advance the distal portion of the delivery catheter, in curves and torque the catheter in small vasculature, particularly the great cardiac vein, is compromised. Another drawback is that in order to fit the anchor and maintain relatively reduced profile, some magnet bulk is removed over past designs, which reduces its magnetic strength. This in turn makes alignment with and attachment to the mating catheter more skill dependent and may require more catheter manipulation. In order to further reduce delivery profile and increase flexibility without loss of magnetic energy, some preferred embodiments of the delivery catheter utilize an anchor that is axially offset from the magnetic head along the longitudinal axis of the catheter, for example, as shown in <FIG>.

<FIG> shows an exemplary delivery catheter configuration <NUM> having a magnetic head <NUM> and a posterior anchor <NUM> that is axially offset from the magnetic head <NUM> along a longitudinal axis of the catheter so as to be non-overlapping with the magnetic head. The posterior anchor <NUM> is disposed over a guidewire <NUM> along which the catheter is advanced through the vasculature. In this embodiment, the magnetic head <NUM> includes a smaller groove <NUM> defined within the magnetic head through which the guidewire lumen <NUM> extends. The magnetic head includes a side hole <NUM> through which the penetrating guidewire can be advanced and from which the bridging element <NUM> extends and attaches to the posterior anchor <NUM> at attachment feature <NUM>. The posterior anchor includes a central portion 1118a that is substantially rigid and that includes the attachment features <NUM> and strain relief portions 1118b on each end that allow flexure so that the distal portion of the catheter can have some flexibility to accommodate curvature of the vasculature through which it is advanced. The strain relief portions 1118b are defined as helical cut portions in the elongate tube defining the posterior anchor <NUM>. In this embodiment, the system includes a reinforced guidewire lumen <NUM> (e.g. braided or coiled wire lumen) to facilitate advancement of the posterior anchor and prevent kinking when advanced along a curved path. An outer jacket <NUM> includes an opening over the exit hole <NUM> and can include a distally tapered portion <NUM> having an opening surrounding a proximal portion of posterior anchor <NUM> and luminal extension <NUM>. Once the bridging element is pulled through the second catheter magnetically coupled to the delivery catheter, as described previously, the posterior anchor <NUM> can be released by withdrawing the guidewire <NUM> and guidewire lumen <NUM>, and can be further facilitated by gently tugging the bridging element <NUM> advanced through the other magnetically coupled catheter. In some embodiments, the posterior anchor <NUM> can be further secured by a releaseable coupling feature, for example a tether or tether loop that engages the posterior anchor to the distal portion of the catheter and that is released by retracting a tether, as previously described.

The primary feature that reduces profile and increases flexibility is the placement of the posterior anchor in front of the magnet and over a guidewire. This design leverages the natural flexural properties of the proximal of the two stress relieving atraumatic ends (e.g. strain relief portions) of the posterior anchor design creating a bending point (see arrow in <FIG>) allowing the distal portion to bend or flex relative the magnetic head portion (see dotted line) to better approximate the curve of a body lumen or vasculature, such as the GCV. Compared to the larger catheter magnet tip profile section described above in <FIG>, the posterior anchor at the tip of the delivery catheter of <FIG> better approximates the natural reducing diameter of the vasculature as the catheter is delivered, advancing it distally.

Because the bending is concentrated to single point between to quasi- rigid sections, transitional construction features can be added to aid in its translational and rotational performance during placement and inhibit kinking at the joint or binding the guidewire. On the inner diameter, a reinforced guidewire lumen <NUM> (e.g. a braided or coiled wire) that spans the full length of the catheter can be used to facilitate advancement of the posterior anchor. In some embodiments, the reinforced guidewire lumen is dimensioned to substantially fill the luminal space between the guidewire and posterior anchor. The outer flexible polymeric luminal extension <NUM> around the anchor that ends at bridging element attachment point stepwise transitions bending of the distal portion of the catheter. On the outer diameter in front of the magnet the distally tapered portion <NUM> can be defined as a flexible conical section to limit the amount of bending over the flex point and acts as a smooth transition against the vasculature wall mitigating disparate diameters of the magnetic head and posterior anchor cross-sections.

Both designs shown in <FIG> allow the delivery of hollow posterior anchors within magnetically connected delivery catheters, largely without exposure of the suture bridge to tissue.

In some embodiments, a releasable coupling, such as a tether connected to the proximal end of the delivery catheter holds the posterior anchor in place during placement and releases the posterior anchor when in place. A stacked design with the posterior anchor partly or completely overlapping with the magnetic head has the advantage of one step location and delivery, but bulk and stiffness limit its distal excursion into smaller vasculature and the design can be more difficult to construct. An offset design with the posterior anchor being offset (e.g. distal or proximal of the magnetic head) allows for passage deeper into the vessel, particularly smaller vasculature, and is easier to construct, however, it may warrant an additional repositioning step for anchor delivery after the initial crossing exposing a short section of suture with magnets unconnected.

In some embodiments, the catheter may include one or more radio-opaque markers to help with translational and rotational alignment of the delivery catheter and facilitate magnetic connection to the mating catheter. It is desirable to align the side hole in the magnetic head of the first catheter with an opening in the second catheter before magnetic coupling as this allows for more consistent, robust magnetic coupling while minimizing skill dependent maneuvering of the catheters to align. In some embodiments, the catheter includes two radio-opaque markers that are asymmetrical in shape and/or location relative the longitudinal axis of the respective catheter so as to indicate a rotational orientation of the catheter and facilitate alignment of a side hole opening in the magnetic head of the catheter with a corresponding lumen opening in a second catheter. For example, the one or more markers can include a first marker on a side of the catheter opposite the side hole and a second marker on the same side as the side hole, the second marker being different in relative location and/or size so as to be readily distinguished from the first marker and aid in determining rotational orientation. It is appreciated that these marker schemes can be used with any of the catheter embodiments described herein.

<FIG> depicts one such system having a first catheter <NUM> and second catheter <NUM>, the first catheter <NUM> having a magnetic head <NUM> (e.g. single, double or three piece magnet) with a side hole opening <NUM> and the second catheter <NUM> having a distal opening <NUM> to be aligned with side hole opening <NUM> for passage of the penetrating wire therethrough to establish access between the catheter. The first catheter includes two radio-opaque markers 1205a, 1205b that are asymmetrical about the longitudinal axis of the first catheter to allow a user to readily determine the rotational orientation of the first catheter before the catheters are brought in close proximity and magnetically coupled. In this embodiment, the marker closest the side hole (marker 1205a) extends further proximally so that it can be readily distinguished from the opposite marker 1205b so that the rotational orientation of the first catheter and relative alignment of the catheters can be readily determined, as can be appreciated by the fluoroscopy image shown in <FIG> depicting a system having such markers. While the markers shown are substantially rectangular and positioned as shown, it is appreciated that various other sizes, shapes and locations of the markers can be utilized in the same manner. For example angled lines pointing to the side hole, triangles and other shapes and sizes to help indicate direction and rotational orientation may be used. Further, it is appreciated that the magnetic heads are also fluoroscopically visible such that the second catheter may not require a separate radio-opaque marker.

<FIG> depicts an example method of delivery and deploying an implants with a catheter system in accordance with aspects of the invention. The method includes steps of: advancing a first catheter along a first vascular path to a vessel of the heart from a first vascular access point, the first catheter having a distal magnetic head adjacent a first anchor and advancing a second catheter along a second vascular path to a chamber of the heart from a second vascular access point, the second catheter having a distal magnetic head. Next, the first and second catheter are positioned so as to magnetically couple the distal magnetic heads across a tissue wall between the chamber and vessel of the heart. Next, penetrating the tissue wall by advancing a puncturing guidewire from the first catheter into the second catheter while magnetically coupled. Advancing the puncturing guidewire to exit from the second vascular access point and pulling the guidewire until an attached bridging element coupled to the first anchor is pulled across the heart chamber and exits at the second vascular access point while first and second catheters are magnetically coupled. The first anchor is then deployed from the first catheter and the first catheter removed. Next, one or more additional anchors can be attached to one or more other portions of the bridging element extending across the heart chamber or through associated vasculature as needed for deployment of a particular type of implant.

In some embodiments, it may be desired to displace or remove the implant after deployment removing any tension and obstruction, allowing access the mitral valve and surrounding tissue. For example, in a few patients, the implant may prove ineffective or another type of implant or procedure may need to be effected (e.g. intravascular valve replacement). Therefore, it would be desirable for a method and devices that allow for subsequent removal of the implant. Removal, at least partial removal, can be effected by cutting of the bridging element. The posterior anchor can be removed by use of conventional catheter techniques, or in some embodiments, can be left in place within the great cardiac vein. The septal anchor typically does not present any concern and can be left in place. Examples of such devices for cutting the bridge element of the implant are shown in <FIG>-265B.

<FIG> shows a bridge cutting catheter <NUM> to facilitate removal of a deployed implant, such as any of those described herein, in accordance with aspects of the invention. Bridge cutting catheter <NUM> includes a curve tipped stylet <NUM> within an inside diameter of the catheter shaft to facilitate steering of the cutting tip to suture bridge <NUM>. The cutting tip includes a cutting blade <NUM> and a capture feature <NUM>. The cutting blade <NUM> includes a sharpened cutting edge along one longitudinally extending side and an angled proximal facing end surface. The capture feature <NUM> is a loop that is angled so as to capture the bridging element <NUM> and direct the bridging element to the cutting edge when the cutting catheter is proximally retracted. Since the bridging element <NUM> is tensioned within the deployed implant, this approach is advantageous in capturing and cutting the bridging element <NUM> with limited visualization. Further the shape of the loop prevents the delicate tissues of the heart from contacting the cutting edge during the procedure. In some embodiments, the cutting catheter is advanced inside a sheath. For example, the cutting catheter can be advanced inside an <NUM>-10F Mullins sheath that has been placed into the LA crossing the septal wall near the outer perimeter of the anterior anchor after a conventional percutaneous septodomy procedure. Some anterior anchor types will allow the delivery catheter to pass through them because of flexible or soft subcomponents or preconstructed fenestrations.

After the cutting tip is advanced from the Mullins catheter, as shown in <FIG>, the bridge cutting catheter <NUM> is positioned beyond the tensioned bridging element <NUM> of the deployed implant and proximally retracted so as to capture the bridging element <NUM> with the capture loop. As shown in <FIG>, once the bridging element is captured, further retraction of the bridge cutting catheter forces the bridging element upwards along the angled proximal-facing end surface of the blade and along the cutting edge, thereby cutting the bridging element, as shown in <FIG>.

While the presence of the cut bridging element <NUM> is often not of concern, there may be instances where it is desired to substantially remove any remaining bridging element <NUM>, for example to prevent flailing suture from entering the valve annulus and potentially interfering with placement of a valve replacement. In such instances, it may be desirable to use a tool that allow for cutting and removal of a substantial portion, or at least a majority, of the bridging element.

<FIG> shows a bridging cutting catheter with suture grip <NUM> for cutting the bridging element and removing excess suture after cutting, in accordance with aspects of the invention. Similar to the bridge cutting catheter in <FIG>, the catheter includes a cutting head with a cutting blade <NUM> and a capture loop <NUM> that are configured and operate in a similar manner as described above. This catheter further includes a suture grip <NUM> to facilitate removal of excess suture. The catheter includes a steerable shaft <NUM> that allow the cutting tip to be steered to the bridge. In this embodiment, the shaft is a double shaft one shaft supporting the cutting tip while the other shaft supports a suture grip <NUM> that holds the bridging element during initial cutting, then operates to wind up excess suture grip, while maintaining the bridging element to allow subsequent cutting and removal of a majority of the bridging element. The suture grip <NUM> can be configured to hold the bridging element (e.g. by friction fit, or between opposable members) and to wind up excess bridging element by rotation of an element extending through a shaft of the catheter.

As shown in <FIG>, cutting catheter <NUM> is positioned adjacent the anterior anchor (not shown) and locking bridge stop <NUM> and positioned to capture tensioned bridging element <NUM> with capture loop <NUM> and hold the bridging element with the suture grip <NUM> (positioned further from the anterior anchor than the cutting blade <NUM>). After initial cutting of the bridging element <NUM> with the cutting element, as described above, the suture grip <NUM> is actuated by rotation of a rotatable member extending through the shaft. This winds up excess suture and also moves the cutting catheter adjacent the posterior anchor, as shown in <FIG>. As the suture grip <NUM> holds the excess suture taut, a second cut can be made with cutting tip, similar to that previously described, thereby removing a majority of the bridging element. The excess suture is retained on the suture grip and removed upon removal of the cutting catheter.

Claim 1:
A delivery system for an implant along a tissue wall in a patient, for treatment of a heart valve in a heart chamber of the patient, the system comprising:
a first catheter (<NUM>) having a proximal and distal end, wherein the first catheter includes a first lumen extending therethrough for passage of a guidewire, wherein the first catheter further includes:
a magnetic head (<NUM>) disposed along a distal portion thereof, wherein the magnetic head (<NUM>) includes magnetic poles oriented laterally relative a longitudinal axis of the first catheter and a guide channel defined therein extending to a side hole (<NUM>) adjacent a first magnetic pole,
a penetrating guidewire advanceable through a second lumen of the first catheter, wherein the penetrating guidewire has a sharpened distal end to facilitate penetration of tissue, and wherein the second lumen is aligned with the guide channel of the magnetic head;
an posterior anchor releasably coupled with the first catheter along the distal portion thereof wherein the anchor is a posterior anchor (<NUM>) axially offset from the magnetic head (<NUM>) along the longitudinal axis of the first catheter and non-overlapping with the magnetic head (<NUM>); and
a bridging element (<NUM>) attached to the posterior anchor (<NUM>) at one end and attached to the penetrating guidewire at an opposite end such that advancement of the penetrating guidewire through the side hole (<NUM>) of the second lumen and across the heart chamber facilitates advancement of the bridging element (<NUM>) across the heart chamber.