Apparatus and method for reducing cardiac valve regurgitation

An apparatus for modifying the annulus of a cardiac valve to reduce regurgitation of blood flow through the cardiac valve includes a first annuloplasty ring having a first diameter and being disposed about a first aspect of the annulus of the cardiac valve. The apparatus also includes an elongate flexible body having proximal and distal end portions and being insertable into the first annuloplasty ring. The elongate flexible body has an adjustable mechanism for selectively adjusting the elongate flexible body from a first relaxed configuration to a second tensioned configuration. The first annuloplasty ring is adaptable to obtain a second smaller diameter and to cause the annulus of the cardiac valve to be modified and reduce regurgitation of blood flow through the cardiac valve when the elongate flexible body obtains the second tensioned configuration.

TECHNICAL FIELD

The present invention relates generally to an apparatus and method for treating cardiac valve insufficiencies, and more particularly to an apparatus and method for reducing or preventing regurgitation of blood flow through a cardiac valve.

BACKGROUND OF THE INVENTION

Mitral and tricuspid valve replacement and repair are traditionally performed with suture techniques. During valve replacement, sutures are spaced around the annulus (the point where the valve leaflet attaches to the heart) and then the sutures are attached to a prosthetic valve. The valve is lowered into position and when the sutures are tied, the valve is fastened to the annulus. The surgeon may remove all or part of the valve leaflets before inserting the prosthetic valve. In valve repair, a diseased valve is left in situ and surgical procedures are performed to restore its function.

Frequently, an annuloplasty ring is used to reduce the size of the annulus. The ring serves to reduce the diameter of the annulus by allowing the leaflets to oppose each other normally and prevent re-dilation of the annulus. Sutures are used to attach a prosthetic ring to the annulus and to assist in plicating the annulus. This procedure, like heart valve replacement, is time-consuming. If the ring is severely malpositioned, then the stitches must be removed and the ring repositioned relative to the valve annulus during restitching. In other cases, a less than optimum annuloplasty may be tolerated by the surgeon rather than lengthening the time of surgery to restitch the ring.

SUMMARY OF THE INVENTION

In one aspect of the present invention, an apparatus for modifying the annulus of a cardiac valve to reduce regurgitation of blood flow through the cardiac valve comprises a first annuloplasty ring having a first diameter and being disposed about a first aspect of the annulus of the cardiac valve, and an elongate flexible body comprising proximal and distal end portions and being insertable into the first annuloplasty ring. The elongate flexible body includes an adjustable mechanism for selectively adjusting the elongate flexible body from a first relaxed configuration to a second tensioned configuration. The first annuloplasty ring is adaptable to obtain a second smaller diameter and to cause the annulus of the cardiac valve to be modified and reduce regurgitation of blood flow through the cardiac valve when the elongate flexible body obtains the second tensioned configuration.

In another aspect of the present invention, a method is provided for modifying the annulus of a cardiac valve to reduce regurgitation of blood flow through the cardiac valve. An apparatus comprising a first annuloplasty ring and an elongate flexible body is first provided. The first annuloplasty ring having a first diameter and is disposed about a first aspect of the annulus of the cardiac valve. The elongate flexible body has proximal and distal end portions and is insertable into the first annuloplasty ring. The elongate flexible body includes an adjustable mechanism for selectively adjusting the elongate flexible body from a first relaxed configuration to a second tensioned configuration. The elongate flexible body is then inserted into the first annuloplasty ring in the first relaxed configuration. Next, the adjustment mechanism is manipulated so that the elongate flexible body obtains the second tensioned configuration and causes the first annuloplasty ring to obtain a second smaller diameter, thereby modifying the annulus of the cardiac valve and reducing regurgitation of blood flow through the cardiac valve. The elongate flexible body is then removed from the first annuloplasty ring.

In another aspect of the present invention, an apparatus for modifying the annulus of a cardiac valve to reduce regurgitation of blood flow through the cardiac valve comprises a first annuloplasty ring having a first diameter and being disposed about a first aspect of the annulus of the cardiac valve, and a flexible body comprising first and second oppositely disposed strut members having proximal and distal end portions. The flexible body additionally includes a cinching mechanism for adjusting the flexible body from a first relaxed configuration to a second tensioned configuration. The cinching mechanism is operatively connected to the distal end portion of the strut members. The cinching mechanism comprises a resistance member operatively coupled to the distal end portion of the strut members, and a harness member operatively coupled to a pull wire extending between the strut members. The flexible body is disposed in a delivery catheter that is insertable into the first annuloplasty ring. The delivery catheter comprises proximal and distal end portions and an opening at the distal portion for extending the harness member therethrough. The flexible body is adaptable to obtain the second tensioned configuration and to cause the first annuloplasty ring to obtain a second smaller diameter so that the annulus of the cardiac valve is modified and regurgitation of blood flow through the cardiac valve is reduced.

In another aspect of the present invention, a method is provided for modifying the annulus of a cardiac valve to reduce regurgitation of blood flow through the cardiac valve. An apparatus comprising a first annuloplasty ring and a flexible body is first provided. The first annuloplasty ring has a first diameter and is disposed about a first aspect of the annulus of the cardiac valve. The flexible body comprises first and second oppositely disposed strut members having proximal and distal end portions and a cinching mechanism for adjusting the flexible body from a first relaxed configuration to a second tensioned configuration. The cinching mechanism comprises a resistance member operatively coupled to the distal end portion of the strut members and a harness member operatively coupled to a pull wire extending between the strut members. The flexible body is disposed in a delivery catheter comprising proximal and distal end portions and an opening at the distal portion for extending the harness member therethrough. The flexible body is inserted into the first annuloplasty ring in the first relaxed configuration, and the cinching mechanism then manipulated so that the first annuloplasty ring obtains a second smaller diameter and modifies the annulus of the cardiac valve to reduce regurgitation of blood flow through the cardiac valve. The flexible body is then removed the first annuloplasty ring.

In another aspect of the present invention, an apparatus for modifying the annulus of a cardiac valve to reduce regurgitation of blood flow through the cardiac valve comprises a first annuloplasty ring having a first diameter and being disposed about a first aspect of the annulus of the cardiac valve, and an electromagnetic wire having proximal and distal end portions. The electromagnetic wire includes a plurality of magnetic members operably connected to the electromagnetic wire and an adjustable mechanism for selectively adjusting the electromagnetic wire from a first relaxed configuration to a second tensioned configuration. The electromagnetic wire is insertable into the first annuloplasty ring. The adjustable mechanism is selectively adjustable so that the first annuloplasty ring is adaptable to obtain a second smaller diameter and modify the annulus of the cardiac valve to reduce regurgitation of blood flow through the cardiac valve.

In another aspect of the present invention, a method is provided for modifying the annulus of a cardiac valve to reduce regurgitation of blood flow through the cardiac valve. An apparatus comprising a first annuloplasty ring and an electromagnetic wire is first provided. The first annuloplasty ring has a first diameter and is disposed about a first aspect of the annulus of the cardiac valve. The electromagnetic wire has proximal and distal end portions and includes a plurality of magnetic members operably connected to the electromagnetic wire. The electromagnetic wire also includes an adjustable mechanism for selectively adjusting the electromagnetic wire from a first relaxed configuration to a second tensioned configuration. The electromagnetic wire is inserted the electromagnetic wire into the first annuloplasty ring in the first relaxed configuration, and the adjustable mechanism is then manipulated so that the electromagnetic wire obtains the second tensioned configuration and the first annuloplasty ring obtains a second smaller diameter to modify the annulus of the cardiac valve and reduce regurgitation of blood flow through the cardiac valve. The electromagnetic wire is then removed from the first annuloplasty ring.

DETAILED DESCRIPTION

The present invention relates generally to an apparatus and method for treating cardiac valve insufficiencies, and more particularly to an apparatus and method for reducing or preventing regurgitation of blood flow through a cardiac valve. As representative of the present invention,FIG. 1illustrates an apparatus10for modifying a cardiac valve12(FIG. 2) comprising a first annuloplasty ring14(FIG. 1) and an elongate flexible body16. The elongate flexible body16is insertable into the first annuloplasty ring14and may be adjusted so that the annulus18of the cardiac valve12(FIG. 2) is modified and regurgitation of blood flow through the cardiac valve is reduced or eliminated.

FIG. 2shows a human heart20. The human heart20contains four chambers: the right and left atria22and24and the right and left ventricles26and28. The thin-walled right atrium22receives deoxygenated blood from the superior vena cava30, the inferior vena cava32, and from the coronary sinus34(FIG. 20). The thin-walled left atrium24(FIG. 2) receives oxygenated blood from pulmonary veins (not shown). The left and right ventricles28and26pump oxygenated and deoxygenated blood, respectively, throughout the body, and the pocket-like pulmonary and aortic semilunar valves36and38prevent reflux into the ventricles. Atrial blood is pumped through the atrioventricular orifices, guarded by the 3-cusp tricuspid valve40on the right and the 2-cusp mitral valve42on the left. The mitral and tricuspid valves42and40are secured to the papillary muscles44in the left and right ventricles28and26by tendinous chordae tendineae46and by the mitral and tricuspid valve annuluses48and50, areas of heart wall tissue at the junction of the atrial and ventricular walls that are relatively fibrous and significantly stronger than leaflet tissue.

As shown inFIG. 3, the first annuloplasty ring14comprises a catheter ring (or sheath)52and a wire catheter (or guide)54disposed within the catheter ring. The catheter ring52may be flexible or rigid. For example, the catheter ring52may be comprised of multiple segments (not shown) configured such that the catheter ring is deformable by tensioning a tensioning member (not shown) coupled to the segments. Alternatively, the catheter ring52may be formed from an elastic material having a geometry selected to engage and optionally shape or constrict the annulus18of the cardiac valve12. For instance, the catheter ring52may be formed from super-elastic material, shape memory alloy such as Nitinol, spring stainless steel, or the like. In other instances, the catheter ring52can be made of a rigid material such as hardened plastic, silicon, polyurethane, or the like. Alternatively, the catheter ring52may be selectively rigidified in situ, such as with a gooseneck or lockable element shaft (not shown), or any other rigidifying structure.

A distal end portion56of the first annuloplasty ring14includes a terminal end58a connecting section60spaced apart by a predetermined length62. The connecting section60includes means64for disconnecting from a main body portion66. For instance, the means64for disconnecting from the main body portion66can comprise first and second ring members68and70respectively attached to the connecting section60and the main body portion. The first ring member68can have a female portion (not shown in detail) capable of mating with a male portion (not shown in detail) of the second ring member70. When separation of the connecting section60from the main body portion66is desired, the main body portion, the connecting section, or both can be rotated or unlocked so that the male portion of the second ring member70is displaced from and thus no longer mated to the female portion of the first ring member68.

Alternative means64for disconnecting from the main body portion66are also possible. For instance, the means64for disconnecting can comprise at least two magnetic members (not shown) each securedly attached to the connecting section60and the main body portion66. When appropriately positioned, the magnetic members may be magnetically attracted so that the connecting section60and the main body portion66are joined. Then, when an appropriate amount of force (e.g., torque) is applied to the main body portion66, the connecting section60, or both, the magnetic members may be sufficiently distanced so that the connecting section and the main body portion are separated.

The connecting section60further includes means72for interconnecting with the terminal end58. As shown inFIG. 3, the means72for interconnecting with the terminal end58can include a receptacle portion74. The receptacle portion74has a shape complementary to the shape of the terminal end58such that the receptacle portion is capable of mating with the terminal end. Additionally, the receptacle portion74can include at least one first magnet76.

As is also shown inFIG. 3, the terminal end58may have a shape complementary to the shape of the receptacle portion74such that the terminal end is capable of mating with the receptacle portion. For instance, the terminal end58may include a threaded portion78capable of mating with the receptacle portion74(which may also have a threaded portion80complementary in shape to the terminal end). Additionally, the terminal end58may include at least one second magnet82.

The distal end portion56of the first annuloplasty ring14includes means84for attaching to the annulus18of the cardiac valve12. The means84for attaching comprises a plurality of deployable hook members86. The deployable hook members86can include any type of fastener, including, for example, C-shaped or semicircular hooks, curved hooks of other shapes, straight hooks, barbed hooks, clips of any kind, T-tags, or any other suitable fastener. The deployable hook members86may be made of any suitable material, such as super-elastic or shape-memory material like Nitinol or spring stainless steel. Additionally, the deployable hook members86may be made of a magnetic or electromagnetic material such as iron, NdFeB, SmCo and Alnico.

The deployable hook members86are integrally secured to the distal end portion56. By “deployable” it is meant that the deployable hook members86can change from a first non-deployed shape (FIG. 9B) to a second deployed shape (FIG. 9C). When deployed, the deployable hook members86may change shape, enter the annulus18of the cardiac valve12, and attach to the annulus of the cardiac valve. Thus, a crimping device or other similar mechanism is not required on the distal end portion56(FIG. 3) to apply force to the deployable hook members86and attach the deployable hook members to the annulus18of the cardiac valve12.

The distal end portion56of the first annuloplasty ring14may additional include at least one magnetic element88. The magnetic element88may be comprised of a ferromagnetic material, such as Fe—C or Fe—Pd, and may be securely disposed about the distal end portion56of the first annuloplasty ring14. The magnetic element88may be magnetically attracted to magnetic elements located on other implantable structures, such as other annuloplasty rings, for example.

Although the first annuloplasty ring14is shown having a circular cross-sectional shape inFIG. 3, the first annuloplasty ring may have any other suitable shape. For example, it may be advantageous to provide a first annuloplasty ring14having an ovoid or elliptical cross-sectional shape (not shown). Such a shape may help ensure that the first annuloplasty ring14is aligned, when positioned in a corner formed by a ventricular wall and a valve leaflet, so that the distal end portion56is optimally oriented to deliver the deployable hook members86into the annulus18of the cardiac valve12. To further enhance contacting to the annulus18of the cardiac valve12and/or orientation of the first annuloplasty ring14, an expandable member (not shown) may also be coupled to the first annuloplasty ring which expands to urge or press the first annuloplasty ring into the corner formed by the ventricle wall and the valve leaflet.

One embodiment of the present invention is illustrated inFIGS. 4A and 4B. As shown inFIG. 4A, an apparatus10for modifying the annulus18of a cardiac valve12comprises a flexible body90having proximal and distal end portions92and94. The flexible body90is comprised of oppositely disposed first and second strut members96and98operably coupled to a cinching mechanism100. The first and second strut members96and98have a thin, wire-like configuration and are comprised of a flexibly resilient material, such as Nitinol or stainless steel.

The flexible body90is disposed in a delivery catheter102having proximal and distal end portions104and106. The delivery catheter102is shaped to facilitate insertion and removal of the delivery catheter into and out of the first annuloplasty ring14. The delivery catheter102may be constructed from a rigid, semi-rigid, or flexible material. For example, the delivery catheter102may be made of a flexible elastic material, such as a shape memory alloy or super-elastic material (e.g., Nitinol, spring stainless steel, or the like). Alternatively, the delivery catheter102may be made of a rigid material such as hardened plastic, silicon, polyurethane, or the like. As shown inFIG. 4A, the distal end portion106of the delivery catheter102has an opening108to facilitate operation of the cinching mechanism100.

The cinching mechanism100is positioned at the distal end portion106of the delivery catheter102. The cinching mechanism100comprises a resistance member110operatively coupled to the distal end portion112of each of the first and second strut members96and98, and a harness member114for contacting at least a portion of the first annuloplasty ring14. The harness member114is operatively coupled to a pull wire116which extends between the first and second strut members96and98. The pull wire116may be comprised of a flexible, semi-flexible, or rigid material, such as Nitinol, stainless steel, plastic polymer, or the like. As described in more detail below, the pull wire116is manipulated to adjust the flexible body90from a first relaxed configuration to a second tensioned configuration.

The resistance member110of the flexible body90is coupled to the distal end portion112of each of the first and second strut members96and98. The resistance member110provides resistance against the first and second strut members96and98when the pull wire116is manipulated, i.e., withdrawn. One example of the resistance member110is illustrated inFIGS. 4A and 4B. The resistance member110has a block-like configuration with first and second sides118and120. A channel122through which the harness member114extends is disposed between the first and second sides118and120. The first side118of the resistance member110is operatively coupled to the distal end portion112of each of the first and second strut members96and98. The resistance member110may be made of any rigid or semi-rigid material, such as hardened plastic or rubber. It should be appreciated that the resistance member110can have any shape or configuration, and is not limited to the block-like configuration illustrated inFIGS. 4A and 4B.

The harness member114can extend through the channel122of the resistance member110to provide a means for contacting a portion of the first annuloplasty ring14. As shown inFIGS. 4A and 4B, the harness member114can comprise an adjustable loop member124having distal and proximal end portions126and128(FIG. 4B). The proximal end portion128of the loop member124is operatively connected to the pull wire116via a connecting ring130or other similar device. The loop member124may be made of a flexible or semi-flexible material, such as a medical grade suture, stainless steel, or Nitinol. The loop member124may be adjusted between a collapsed configuration (FIG. 4A) and an open configuration (FIG. 4B).

The pull wire116is used to adjust the configuration of the loop member124. For example, when the pull wire116is withdrawn as inFIG. 4A, the proximal end portion128of the loop member124is pulled through the channel122of the resistance member110. As the proximal end portion128of the loop member124is threaded through the channel122, the distal end portion126of the loop member is progressively collapsed. When a radial force is applied to the pull wire116as inFIG. 4B, the distal and proximal end portions126and128of the loop member124are progressively threaded through the opening108of the delivery catheter102and the channel122(respectively). As the distal end portion126is exuded from the opening108, the distal end portion of the loop member124is expanded and obtains the open configuration.

As shown inFIGS. 5A-C, the proximal end portion128of the loop member124can comprise a variety of configurations to facilitate movement of the loop member through the channel122. InFIG. 5A, for example, the proximal end portion128of the loop member124is comprised of oppositely disposed strands132. When the pull wire116is withdrawn, the strands132are progressively meshed together as the strands move through the channel122and, in turn, reduce the size of the distal end portion126of the loop member124. The proximal end portion128of the loop member124can also comprise a click-and-groove mechanism (not shown in detail) as shown inFIG. 5B. When the pull wire116is withdrawn, the click-and-groove mechanism is progressively ratcheted through the channel122of the resistance member110to reduce the size of the distal end portion126of the loop member124. The proximal end portion128can additionally comprise a zipper-like mechanism (not shown in detail) as illustrated inFIG. 5C. When the pull wire116is withdrawn, the teeth of the zipper mechanism are progressively mated and the size of the distal end portion126of the loop member124is progressively reduced.

It should be appreciated that the harness member114can have a variety of configurations other than the loop member124illustrated inFIGS. 4A and 4B. For example, the harness member114may comprise a deformable member (not shown), such as a deformable hook or clip, made of a shape memory alloy or other like material. The deformable member may have a linear native conformation and may be selectively extended and retracted through the opening108of the delivery catheter102. When the deformable member is extended from the delivery catheter102, the deformable member may be modified by delivering energy (e.g., thermal or electromagnetic energy) to the deformable member. Delivering energy to the deformable member may cause the deformable member to obtain an arcuate configuration adapted for contacting a portion of the first annuloplasty ring14.

As will be discussed in greater detail below, the cinching mechanism100may be manually manipulated (i.e., by adjusting the pull wire116) to adjust the flexible body90from a first relaxed configuration to a second tensioned mechanism. By “first relaxed configuration,” it is meant that little or no manual force has been applied to the pull wire116of the flexible body90. Consequently, the flexible body90obtains a pliable or malleable configuration to facilitate placement of the flexible body in the first annuloplasty ring14. By “second tensioned configuration,” it is meant that some manual force has been applied to the pull wire116so that the flexible body90obtains a rigid or semi-rigid configuration to facilitate modification of the first annuloplasty ring14. By placing the flexible body90into the first annuloplasty ring14in the first relaxed configuration and then adjusting the cinching mechanism100, the flexible body obtains the second tensioned configuration and thereby modifies the first annuloplasty ring to reduce regurgitation of blood flow through the cardiac valve12.

A second embodiment of the present invention is illustrated inFIGS. 6A and 6Band comprises a flexible body90, a first annuloplasty ring14, and a second annuloplasty ring134. The second annuloplasty ring134may be disposed about a second aspect136of the cardiac valve annulus18to facilitate positioning of the first annuloplasty ring14. As shown inFIG. 6A, the second annuloplasty ring134may be identically constructed as the first annuloplasty ring14. Alternatively, the second annuloplasty ring134can comprise any other type of annuloplasty ring known in the art. For example, the second annuloplasty ring134can have an annular shape or configuration which is partial (i.e., has an open configuration) or continuous (i.e., has a closed configuration). The second annuloplasty ring134can include flexible, semi-rigid and rigid devices having shapes which are circular, D-shaped, C-shaped, saddle-shaped and any other annular or non-annular shape suitable for repairing cardiac valves. The second annuloplasty ring134may additionally comprise at least one magnetic element (not shown) to facilitate positioning of the first annuloplasty ring14.

The present invention also provides a percutaneous method for modifying the annulus18of a cardiac valve12to reduce regurgitation of blood flow through the cardiac valve. In one embodiment of the method, a first step comprises accessing the annulus18of the cardiac valve12and measuring the dimensions of the annulus. Access to the annulus18may be accomplished by any available technique, including intravascular (described below), transthoracic, and the like. The method of the present invention will typically entail gaining access to a beating heart20; however, the present invention may also be used for intravascular stopped-heart access as well as stopped-heart open chest procedures.

Prior to use of the apparatus10, the dimensions of the cardiac valve18will need to be determined. Various methods and devices for determining the dimensions of the annulus18of the cardiac valve12are known in the art, such as echocardiogram, computed tomography (CT), magnetic resonance imaging (MRI), fluoroscopy, and angiography. After determining the dimensions of the cardiac valve18, an appropriately-sized first annuloplasty ring14having a suitably sized predetermined length62is chosen. The first annuloplasty ring14is suitably sized so that the dimensions of the distal end portion56of the first annuloplasty ring14correspond to the dimensions of the annulus18of the cardiac valve12. For instance, a first annuloplasty ring14having a distal end portion56approximately equal to the circumference of the annulus18of the cardiac valve12may be selected.

Next, the first annuloplasty ring14is inserted into the vasculature of a patient to repair, for example, a regurgitant mitral valve42(FIGS. 7A and 7B). Where an intravascular approach is desired, the first annuloplasty ring14may be inserted through a femoral artery or vein (not shown) via a delivery catheter102. Alternatively, the first annuloplasty ring14may be inserted through the internal jugular vein (not shown). Further, the first annuloplasty ring14may be inserted using a transthoracic approach by introducing the first annuloplasty ring into the heart20via a minimally invasive incision or port on the heart wall.

Once the first annuloplasty ring14is inserted into the vasculature of the patient, the first annuloplasty ring is guided toward a first aspect of the cardiac valve annulus138, such as a superior aspect140of the mitral valve annulus48. The first annuloplasty ring14is inserted into an internal jugular vein (not shown), through the superior vena cava30into the right atrium22, across the interatrial septum (not shown) to the left atrium24, and then around the mitral annulus48. Using tactile means, for example, the first annuloplasty ring14is guided toward the left atrium24. It should be appreciated that other means may be used to guide the first annuloplasty ring14. For instance, the first annuloplasty ring14may be guided toward the left atrium24using magnetic guidance, such as the Stereotaxis® Magnetic Navigation System, or robotic guidance to remotely control delivery of the first annuloplasty ring.

It should be appreciated that access to the superior aspect140of the mitral annulus48may also be gained via a femoral vein (not shown) by urging the first annuloplasty ring14through the inferior vena cava32into the right atrium22, through the interatrial septum into the left atrium24, and around the mitral annulus. Further, it should be appreciated that the first annuloplasty ring14may be delivered to an inferior aspect142of the mitral valve annulus48, such as a subvalvular space (not shown in detail), roughly defined as the left ventricular side of the mitral annulus48.

Once the first annuloplasty ring14has been suitably positioned at the first aspect138of the mitral annulus48(FIGS. 8A and 8B), the distal end portion56is attached to the mitral annulus by adjusting the deployable hook members86from a non-deployed configuration (FIGS. 9A and 9B) to a deployed configuration (FIG. 9C). The deployable hook members86may be deployed in a variety of ways. For instance, the deployable hook members86may be deployed via an electromagnetic mechanism (not show). The electromagnetic mechanism can comprise an electromagnetic wire (not show) operably linked to the deployable hook members86. The electromagnetic wire can comprise the wire catheter54or, alternatively, an additional wire (not shown). The electromagnetic wire may also be operably linked to a battery or other power source capable of generating electricity. When electricity is supplied to the wire, the deployable hook members86change from the non-deployed configuration to the deployed configuration.

The deployable hook members86may also be deployed via a camming mechanism (not shown). The camming mechanism may comprise a tensioning wire (not shown) operably linked to the deployable hook members86. When the tensioning wire is manipulated, the deployable hook members86change from the non-deployed configuration to the deployed configuration. Alternatively, the deployable hook members86may be deployed as a result of the first annuloplasty ring14assuming a particular confirmation (e.g., by changing the first annuloplasty ring from a linear configuration to a circular or annular configuration). Also, an inflatable member (not shown) disposed within the first annuloplasty ring14may cause the deployable hook members86to deploy when inflated.

After the distal end portion56of the first annuloplasty ring14is secured to the mitral annulus48, the flexible body90is inserted into the main body portion66in a first relaxed configuration and then urged into the distal end portion of the first annuloplasty ring. When the distal end portion94of the flexible body90is positioned at the distal end portion56, the terminal end58is then urged toward the connecting section60of the first annuloplasty ring14. A radial force (indicated by the arrow) is next applied to the pull wire116of the flexible body90so that the loop member124extends through the opening108of the delivery catheter102and through the terminal end58of the first annuloplasty ring14(FIG. 10). As the loop member124is progressively exuded from the first annuloplasty ring14, the distal end portion94obtains an open, lasso-like configuration as shown inFIG. 12. The position of the loop member124is then adjusted so that the loop member contacts a portion of the first annuloplasty ring14.

As shown inFIG. 10, the loop member124is positioned so that the distal end portion126ensnares a portion of the first annuloplasty ring14. More particularly, the loop member124is positioned so that the distal end portion126ensnares an anchor member144located in the receptacle portion74of the first annuloplasty ring14. The anchor member144provides a means for connecting the distal end portion126of the loop member124with the first annuloplasty ring14. InFIG. 10, for example, the anchor member144has a stub-like configuration; however, it will be appreciated that the anchor member may comprise any other form or shape capable of providing a secure point of contact with the harness member114. By connecting the loop member124to the first annuloplasty ring14, the diameter of the first annuloplasty ring may be modified (i.e., reduced) by withdrawing the pull wire116. AlthoughFIG. 10depicts the anchor member144in the receptacle portion74of the first annuloplasty ring14, it will be appreciated that the anchor member may be located anywhere on the first annuloplasty ring so long as the distal end portion126of the loop member124can contact the anchor member.

As shown inFIG. 11, the pull wire116may then be withdrawn so that the distal end portion126of the loop member124is snugly cinched around the anchor member144and the terminal end58of the first annuloplasty ring14is pulled toward the receptacle portion74. The terminal end58is securely interconnected to the connecting section60by manipulating the terminal end so that the threaded portion78is progressively threaded into the threaded portion80of the receptacle portion74. As the terminal end58is progressively threaded into the receptacle portion74, the diameter of the distal end portion56of the first annuloplasty ring14progressively shrinks so that the annulus48of the mitral valve42is remodeled. Once a complete ring14is formed, the diameter of the first annuloplasty ring may be adjusted by further withdrawing the pull wire116. It is contemplated that the image guidance (e.g., MRI, CT, fluoroscopy, ultrasound, angiogram, or combinations thereof) may be used to monitor the degree to which the diameter of the distal end portion56is shrinking as the pull wire116is withdrawn.

The diameter of the first annuloplasty ring14may continue to be adjusted so that the leaflets of the mitral valve42properly coapt (FIG. 12) and regurgitation of blood flow through the mitral valve is reduced or eliminated. The distal end portion126of the loop member124is then loosened from the anchor member144and retracted into the delivery catheter102. The flexible body90is withdrawn from the first annuloplasty ring14(FIG. 12), and the main body portion66is disconnected from the connecting section60by applying a force (e.g., torque) sufficient to separate the first and second ring members68and70. After the connecting section60and the main body portion66are disconnected, the main body portion is retracted and the medical procedure completed. With the distal end portion56of the first annuloplasty ring14now securely attached to the mitral annulus48, the mitral valve42is successfully remodeled and the patient is provided with a normally functioning mitral valve.

It should be appreciated that the method described above may be varied as needed. In one variation, for example, a first annuloplasty ring14may be sized and then percutaneously delivered to a superior aspect140of the mitral valve annulus48(as described above). After the first annuloplasty ring14is appropriately positioned about the mitral annulus48, the flexible body90may then be inserted into the first annuloplasty ring and threaded into the distal end portion56of the first annuloplasty ring (as described above).

When the distal end portion94of the flexible body90is appropriately positioned at the distal end portion56of the first annuloplasty ring14, the terminal end58may be urged toward the connecting section60. A radial force may then be applied to the pull wire116so that the loop member124extends through the opening108of the delivery catheter102and through the terminal end58of the first annuloplasty ring14. Either simultaneous with or shortly after extending the loop member124, the deployable hook members86may then be deployed as described above to secure the distal end portion56of the first annuloplasty ring14to the mitral annulus48. As described above, the distal end portion126of the loop member124may then be contacted with an anchor member144and appropriately adjusted to form a completed first annuloplasty ring14. The flexible body90and the first annuloplasty ring14may then be adjusted further so that regurgitation of blood flow through the mitral valve42is reduced or eliminated. The flexible body90and the main body portion66of the first annuloplasty ring14may then be removed from the patient and the procedure completed (as described above).

In another variation of the method, a first annuloplasty ring14may be sized and percutaneously delivered a superior aspect140of the mitral valve annulus48as described above. Once the first annuloplasty ring14has been suitably positioned in the left atrium24, the terminal end58of the first annuloplasty ring may be guided toward the connecting section60. When the terminal end58is positioned adjacent the connecting section60, the second magnet82of the terminal end may be magnetically attracted to the first magnet76of receptacle portion74so that the terminal end and the connecting section are magnetically held in contact. Consequently, the distal end portion56of the first annuloplasty ring14may be formed into a circular or annular shape. The distal end portion56may then be positioned adjacent the superior aspect140of the mitral annulus48and secured thereto by deploying the deployable hook members86as described above.

Next, the terminal end58of the first annuloplasty ring14may be securely interconnected with the connecting section60to form a ring (as described above). After the first annuloplasty ring14is securely positioned about the mitral annulus48, the flexible body90may be inserted into the first annuloplasty ring as described above. The cinching mechanism100of the flexible body90may then be operated as described above to adjust (i.e., reduce) the diameter of the distal end portion56of the first annuloplasty ring14and modify the mitral annulus48so that the mitral leaflets properly coapt and regurgitation of blood flow through the mitral valve42is reduced or eliminated. The flexible body90and main body portion66of the first annuloplasty ring14may then be removed and the medical procedure completed (as described above).

An alternate embodiment of the method comprises using a flexible body90, a first annuloplasty ring14, and a second annuloplasty ring134to remodel the annulus18of a cardiac valve12to reduce regurgitation of blood flow through the cardiac valve. As described above, the second annuloplasty ring134can comprise any type of annuloplasty ring known in the art and described above. Alternatively, the second annuloplasty ring134may be identically constructed as the first annuloplasty ring14. Where the second annuloplasty ring134is identically constructed as the first annuloplasty ring14, the second annuloplasty ring may first be sized to a second aspect136of the mitral annulus48, such as an inferior aspect142of the mitral valve annulus48, in a manner similar to the first annuloplasty ring14(described above).

The first annuloplasty ring14may then be inserted into the vasculature of a patient as described above and urged toward the first aspect138of the mitral valve42. After inserting the first annuloplasty ring14, the second annuloplasty ring134may be inserted into the vasculature of the patient. For instance, the second annuloplasty ring134may be inserted into a femoral artery (not shown), across the aortic arch146, through the aortic valve38, and into the left ventricle28. After delivering the first and second annuloplasty rings14and134to the superior and inferior aspects140and142of the mitral annulus48, respectively, the deployable hook members86of each of the first and second annuloplasty rings may be deployed (as described above) to respectively secure the first and second annuloplasty rings to the superior and inferior aspects of the mitral valve. At least one magnetic element88of the first annuloplasty ring may be magnetically attracted to at least one magnetic element of the second annuloplasty ring134so that the first and second annuloplasty rings are magnetically coupled together and the mitral annulus48is fit between the first and second annuloplasty rings.

Next, the terminal end58of the second annuloplasty ring134is guided toward the connecting section60of the second annuloplasty ring. When the terminal end58of the second annuloplasty ring134is positioned adjacent the connecting section60, the second magnet82of the terminal end is magnetically attracted to the first magnet76of the receptacle portion74so that the distal end portion56of the second annuloplasty ring is magnetically held in contact with the connecting section of the second annuloplasty ring.

The terminal end58of the second annuloplasty ring134may then be interconnected with the connecting section60to form a continuous ring. The terminal end58of the second annuloplasty ring134may be securely interconnected to the connecting section60by manipulating the terminal end so that the threaded portion78of the second annuloplasty ring is progressively threaded into the threaded portion80. As the terminal end58of the second annuloplasty ring134is progressively threaded into the receptacle portion74, the distal end portion56of the second annuloplasty ring134may be securely attached to the second aspect136of the mitral annulus48. After the distal end portion56of the second annuloplasty ring134is secured about the inferior aspect142of the mitral annulus48, the connecting section60of the second annuloplasty ring may be disconnected from the main body portion66and the main body portion retracted from the vasculature of the patient.

With the second annuloplasty ring134secured about the inferior aspect142of the mitral valve annulus48, the flexible body90may be inserted into the first annuloplasty ring14and advanced to the distal end portion56of the first annuloplasty ring, as described above. The cinching mechanism100of the flexible body90may then be adjusted so that the flexible body obtains the second tensioned configuration, thereby causing the first annuloplasty ring14to modify the mitral annulus48so that the mitral leaflets properly coapt. The flexible body90and the main body portion66of the first annuloplasty ring14may then be retracted from the vasculature of the patient as described above. With the distal end portion56of each of the first and second annuloplasty rings14and134respectively secured to the superior and inferior aspects140and142of the mitral valve annulus48as shown inFIGS. 6A and 6B, the mitral annulus48is remodeled to reduce or eliminate regurgitation of blood flow through the mitral valve.

Another embodiment of the present invention is illustrated inFIGS. 13-24. The apparatus10ais identically constructed as the apparatus10shown inFIG. 1, except where as described below. InFIG. 13-24, structures that are identical as structures inFIG. 1use the same reference numbers, whereas structures that are similar but not identical carry the suffix “a”.

An apparatus10afor modifying the annulus18of a cardiac valve14to reduce regurgitation of blood flow through the cardiac valve comprises a first annuloplasty ring14(FIG. 3) and an elongate flexible body16a(FIG. 13). The elongate flexible body166acomprises an electromagnetic wire148having proximal and distal end portions150and152. It should be appreciated that the term “wire” as used herein is a broad term having its normal and customary meaning and includes, without limitation, mesh, flat, round, band-shaped, and rod-shaped members. The electromagnetic wire148includes a plurality of magnetic members154operably connected to the electromagnetic wire, and an adjustable mechanism (not shown in detail) for adjusting the electromagnetic wire from a first relaxed configuration to a second tensioned configuration.

The electromagnetic wire148and the magnetic members154are comprised of a ferromagnetic material. The term “ferromagnetic” as used herein is a broad term and is used in its ordinary sense and includes, without limitation, any material that easily magnetizes, such as a material having atoms that orient their electron spins to conform to an external magnetic field. Ferromagnetic materials include a variety of permanent magnets, which can be magnetized through a variety of modes, and materials, such as metals, that are attracted to permanent magnets. Ferromagnetic materials are capable of being activated by an electromagnetic transmitter, such as one located outside of a patient.

Ferromagnetic materials can include at least one of Fe—C, Fe—Pd, Fe—Mn—Si, Co—Mn, Fe—Co—Ni—Ti, Ni—Mn—Ga, Ni2MnGa, and Co—Ni—Al. Ferromagnetic materials may also include one or more polymer-bonded magnets, wherein magnetic particles are bound within a polymer matrix, such as a biocompatible polymer. Ferromagnetic materials of the present invention can additionally comprise isotropic and/or anisotropic materials, such as for example NdFeB, SmCo, ferrite and/or AlNiCo particles. The biocompatible polymer can comprise, for example, polycarbonate, silicone rubber, polyurethane, silicone elastomer, a flexible or semi-rigid plastic, combinations of the same and the like.

As shown inFIG. 13, an external energy source156for delivering electromagnetic energy to the electromagnetic wire148may be operably coupled to the proximal end portion150of the electromagnetic wire. Alternatively, the external energy source156may be wirelessly coupled to the electromagnetic wire148(FIGS. 14A and 14B). The energy source156may include, for example, radio frequency (RF) energy, X-ray energy, microwave energy, acoustic or ultrasound energy such as focused ultrasound or high intensity focused ultrasound energy, light energy, electric field energy, laser energy, magnetic field energy, combinations of the same, or the like.

The magnetic members154(FIG. 13) facilitate modification of the electromagnetic wire148from the first relaxed configuration to the second tensioned configuration. In the first relaxed configuration, for example, electromagnetic energy is not applied to the electromagnetic wire148and the electromagnetic wire obtains a pliable or flexible configuration. The first relaxed configuration facilitates placement of the electromagnetic wire148into the first annuloplasty ring14. When electromagnetic energy is delivered to the electromagnetic wire148, each of the magnetic members154is magnetically polarized. Opposing magnetic poles of adjacent magnetic members154are then attracted to one another. The magnetic force between the magnetic members154causes the magnetic members to gravitate towards one another and the electromagnetic wire148to shrink and obtain the second tensioned configuration. The number and shapes selected for the magnetic members154may depend, at least in part, on factors such as the desired field to be produced, the resulting mutual force or forces between the magnetic members, or the like.

As discussed in greater detail below, the electromagnetic wire148may be inserted into the first annuloplasty ring14in the first relaxed configuration and then magnetized by the external energy source156so that the electromagnetic wire obtains the second tensioned configuration. When the electromagnetic wire148obtains the second tensioned configuration, the diameter of the first annuloplasty ring148may be uniformly modified, i.e., reduced in 360°. Alternatively, by selectively depositing an insulative material (e.g., a rubber or plastic polymer) on the electromagnetic wire148, only select portions of the first annuloplasty ring, such as portions spaced approximately 180° apart, may be reduced when electromagnetic energy is applied to the electromagnetic wire.

Another embodiment of the present invention comprises an electromagnetic wire148, a first annuloplasty ring14, and a second annuloplasty ring134(FIGS. 14A and 14B). As described above, the second annuloplasty ring134may be disposed about a second aspect136of a cardiac valve12, such as an inferior aspect142of the mitral valve annulus48(FIGS. 15A and 15B), and may comprise any type of annuloplasty ring known in the art. The second annuloplasty ring134may facilitate placement of the first annuloplasty ring14about a superior aspect140of the mitral valve annulus48, for example.

In another embodiment of the present invention, the apparatus10amay be percutaneously delivered to modify the annulus18of a cardiac valve12to reduce regurgitation of blood flow through the cardiac valve. For example, the apparatus10acan be percutaneously delivered to a first aspect138of a cardiac valve12, such as a superior aspect140of the mitral valve annulus48, to reduce or eliminate regurgitation of blood flow through the mitral valve.

The mitral annulus48and the first annuloplasty ring14may be sized as described above. Next, the first annuloplasty ring14may be delivered to the left atrium24and securely positioned about the mitral annulus48(FIGS. 16 and 17) as described above. An electromagnetic wire148having a first relaxed configuration may then be inserted into the main body portion66and urged into the distal end portion56of the first annuloplasty ring14(FIG. 18).

Once the distal end portion152of the electromagnetic wire148is appropriately positioned in the first annuloplasty ring14, electromagnetic energy (e.g., RF energy) may be delivered to the electromagnetic wire (FIG. 19) via the external energy source156. As shown inFIG. 20, a positioning catheter158may be used to facilitate placement of the first annuloplasty ring14about the mitral annulus48. The positioning catheter158can comprise a plurality of discrete magnets160disposed within a delivery sheath162. The positioning catheter158may be inserted into the vasculature of the patient and then advanced into the coronary sinus34approximately adjacent the mitral annulus48(FIG. 21). As the first annuloplasty ring14is being aligned and placed near the mitral annulus48, the magnet element(s)88of the first annuloplasty ring may be magnetically attracted to the positioning catheter158across the atrial wall (FIG. 22). The position of the positioning catheter158may then be further adjusted to place the first annuloplasty ring14as desired.

Once the electromagnetic wire148is appropriately positioned, the electromagnetic wire may be magnetized by delivering electromagnetic energy to the electromagnetic wire. Delivery of electromagnetic energy magnetizes the magnetic members154and causes the magnetic members to be magnetically attracted to one another. The magnetic attraction then causes the magnetic members154to gravitate towards one another, thereby causing the electromagnetic wire148to shrink and obtain the second tensioned configuration. Consequently, the first diameter (as shown by the dashed lines inFIG. 19) of the first annuloplasty ring14is reduced and the annulus48of the mitral valve42is modified so that the mitral leaflets properly coapt and regurgitation of blood flow through the mitral valve is reduced or eliminated.

After the first annuloplasty ring14is properly adjusted, the proximal end portion150of the electromagnetic wire148may be disconnected from the distal end portion152and removed from the vasculature of the patient (FIG. 24). The main body portion66may also be disconnected from the distal end portion56of the first annuloplasty ring14as described above. It should be appreciated that the method for percutaneously modifying a cardiac valve12using the apparatus10ais not limited to the sequence described above and, rather, that any combination of the above-described steps may be used to reduce regurgitation of blood flow through the cardiac valve.

Referring toFIGS. 14A and 14B, an alternate embodiment of the method comprises using first and second annuloplasty rings14and134to reduce regurgitation of blood flow through a cardiac valve12. For example, first and second annuloplasty rings14and134may be respectively delivered to the superior and inferior aspects140and142of the mitral valve annulus48to reduce or eliminate mitral regurgitation. The second annuloplasty ring134may be identically constructed as the first annuloplasty ring14. As described above, both the first and second annuloplasty rings14and134may then be delivered to the superior and inferior aspects140and142of the mitral valve annulus48, respectively, as shown inFIGS. 14A and 14B.

As shown inFIG. 23, a positioning catheter158may be used to facilitate placement of the first and second annuloplasty rings14and134about the superior and inferior aspects140and142of the mitral annulus48(respectively). As described above, the positioning catheter158can comprise a plurality of discrete magnets160disposed within a delivery sheath162. The positioning catheter158may be inserted into the vasculature of the patient and then advanced into the coronary sinus34approximately adjacent the mitral annulus48. As the first and second annuloplasty rings14and134are being aligned and placed near the superior and inferior aspects140and142of the mitral annulus48(respectively), the magnet element(s)88of the first and second annuloplasty rings may be magnetically attracted to the positioning catheter158across the atrial wall (FIG. 23). The position of the positioning catheter158may then be further adjusted to place the first and second annuloplasty rings14and134as desired.

After the distal end portion56of each of the first and second annuloplasty rings14and134are respectively secured about the superior and inferior aspects140and142of the mitral valve annulus48, an electromagnetic wire148may be inserted into the first annuloplasty ring as shown inFIGS. 14A and 14B. When the electromagnetic wire148is appropriately positioned in the first annuloplasty ring14, electromagnetic energy (e.g., RF energy) may be delivered to the electromagnetic wire (FIGS. 15A and 15B). Delivery of RF energy adjusts the electromagnetic wire148from the first relaxed configuration to the second tensioned configuration as described above. When the electromagnetic wire148obtains the second tensioned configuration, the diameter of the distal end portion56of the first annuloplasty ring14is reduced so that the mitral leaflets properly coapt and regurgitation of blood flow through the mitral valve42is reduced or eliminated (FIGS. 15A and 15B). The proximal end portion150of the electromagnetic wire148and the main body portion66of the first annuloplasty ring14may then be retracted and the procedure completed as described above.

Another embodiment of the present invention is illustrated inFIGS. 25A-27. The apparatus10bis identically constructed as the apparatus10shown inFIG. 1, except where as described below. InFIG. 25A-27, structures that are identical as structures inFIG. 1use the same reference numbers, whereas structures that are similar but not identical carry the suffix “b”.

An apparatus10bfor modifying the annulus18of a cardiac valve12to reduce regurgitation of blood flow through the cardiac valve comprises a first annuloplasty ring14(FIG. 3) and an elongate flexible body16b(FIGS. 25A and 25B). The elongate flexible body16bcan comprise first and second wires164and166having proximal and distal end portions168and170. The first and second wires164and166can be made of a flexible or semi-rigid material such as stainless steel, Nitinol, titanium, plastic polymer, or the like. The first and second wires164and166may be made from a shape memory alloy or, alternatively, from a ferromagnetic material (as described above). The distal end portion170of each of the first and second wires164and166may respectively include first and second magnetic members172and174. The first and second magnetic members172and174may be identically constructed as the magnetic members154described above.

As shown inFIGS. 25A and 25B, the first and second wires164and166may be inserted into the first annuloplasty ring14in a first relaxed configuration. More particularly, the distal end portion170of the first wire164may be positioned at the terminal end58of the first annuloplasty ring14, and the distal end portion of the second wire166may be positioned near the means for disconnecting64of the first annuloplasty ring. As described above, the distal end portion56of the first annuloplasty ring14may then be coupled around the superior aspect140of the mitral annulus48, for example, by urging the terminal end58towards the receptacle portion74of the first annuloplasty ring (FIGS. 26A and 26B).

When the terminal end58and the receptacle portion74of the first annuloplasty ring14are positioned near one another, the first and second magnetic members172and174are respectively attracted to one another and pull the terminal end and the receptacle portion together. The distal end portion56of the first annuloplasty ring14may now encircle the superior aspect140of the mitral valve annulus48, and the deployable hook members86deployed (as described above) to secure the distal end portion. Next, the proximal end portion168of each of the first and second wires164and166may be manipulated so that the first and second wires obtain the second tensioned configuration (FIG. 27). For example, the proximal end portion168of each of the first and second wires164and166may be withdrawn so that the distal end portion56of the first annuloplasty ring14is tightened, thus causing the mitral leaflets to coapt properly and reduce or eliminate regurgitation of blood flow through the mitral valve42. Alternatively, the flexible body90may be used to ensnare a portion of the first and second wires164and166and then manipulated to withdraw the first and second wires.

After the distal end portion56of the first annuloplasty ring14is appropriately adjusted and regurgitation of blood flow through the mitral valve42is reduced or eliminated, the proximal end portion168of each of the first and second wires164and166may be disconnected from the distal end portion170of each of the first and second wires and retracted from the vasculature of the patient. Additionally, the main body portion66of the first annuloplasty ring14may be disconnected from the distal end portion56and also retracted from the vasculature of the patient

From the above description of the invention, those skilled in the art will perceive improvements, changes and modifications. For example, the present invention may be placed via a minimally invasive, transthoracic approach via a port on the heart wall or, alternatively, via an open-chest procedure under direct supervision. Additionally, it will be appreciated that the present invention can be used to modify the annulus of other cardiac valves, such as the tricuspid and aortic valves40and38. Such improvements, changes and modifications within the skill of the art are intended to be covered by the appended claims.