Retaining mechanisms for prosthetic valves
Disclosed herein are representative embodiments of methods, apparatus, and systems used to deliver a prosthetic heart valve to a deficient valve. In one embodiment, for instance, a support member is positioned to at least partially surround the native leaflets of a valve. A locking member is used to couple both ends of the support member, forming a support band. An expandable prosthetic heart valve is delivered into the native heart valve and expanded while the expandable prosthetic valve is at least partially within the support band, thereby causing one or more of the native leaflets of the native heart valve to be frictionally secured between the support band and the expanded prosthetic heart valve.
1. A method, comprising:
advancing a support member so that the support member at least partially surrounds native leaflets of a heart valve, the support member comprising a locking member coupled to a proximal end of the support member;
advancing a distal end of the support member to engage the locking member and couple the distal end of the support member to the locking member to form a closed loop support band that at least partially surrounds the native leaflets; and
expanding a prosthetic heart valve inside the closed loop support band so that the native leaflets are in contact with an outside surface of the prosthetic device and an inside surface of the support band.
2. The method of claim 1 , wherein the support member comprises an internal lumen and the act of advancing the support member comprises:
advancing a guidewire to an outflow side of a mitral valve;
advancing the guidewire at least partially surround the native leaflets; and
advancing the internal lumen of the support member over the guidewire.
3. The method of claim 2 , wherein the act of advancing the internal lumen of the support member comprises advancing a proximal end of the locking member using a pusher tube.
4. The method of claim 2 , wherein the act of advancing the guidewire to at least partially surround the native leaflets comprises:
advancing a precurved catheter out of a delivery catheter, the precurved catheter configured to bend in a predetermined manner when it is advanced out of the delivery catheter;
advancing the guidewire out of the precurved catheter, the guidewire being precurved so that it will bend to form a generally circular shape when advanced from the precurved catheter; and
advancing the guidewire in the generally circular shape until the guidewire at least partially surrounds the leaflets.
5. The method of claim 4 , wherein the guidewire forms a circular shape that is in a plane that is generally perpendicular to a longitudinal axis of the delivery catheter.
6. The method of claim 4 , further comprising:
advancing a snare catheter out of the delivery catheter to capture a distal end of the guidewire; and
pulling the distal end of the guidewire into a receiving area of the locking member, the receiving area being configured to receive and engage the distal end of the support member.
7. The method of claim 1 , wherein the native heart valve is a mitral valve and the act of advancing the support member so that the support member at least partially surrounds the native leaflets comprises:
advancing the support member to at least partially surround chordae tendineae associated with both native leaflets of the mitral valve.
8. The method of claim 1 , wherein the support member is delivered percutaneously and the prosthetic heart valve is delivered transapically.
9. The method of claim 1 , wherein the support member and prosthetic heart valve are delivered transapically.
10. The method of claim 1 , wherein the locking member comprises a receiving area and the act of advancing the distal end of the support member to engage the locking member comprises:
advancing the distal end of the support member into the receiving area and securing the distal end of the support member in the receiving area.
11. The method of claim 10 , wherein the distal end of the support member comprises a nose cone with a grooved section and the act of securing the distal end of the support member comprises:
advancing the grooved section of the nose cone until a biased tab member engages the grooved section of the nose cone to restrict proximal movement of the nose cone relative to the locking member.