Methods and apparatus for engaging a valve prosthesis with tissue
A prosthetic valve comprises a self-expanding frame which includes a self-expanding atrial skirt that forms a flanged region, a self-expanding ventricular skirt, and a first self-expanding tab coupled with the ventricular skirt. A receptacle for receiving a valve leaflet is formed by the area bounded by an outer surface of the atrial skirt, an outer surface of the ventricular skirt, and an inner surface of the first tab. The receptacle has a window for receiving the valve leaflet that is defined by a gap between an edge of the flange and a tip of the first tab. The gap is maximized when the tip of the first tab is unconstrained and a base of the first tab is at least partially constrained. The gap is minimized when the tip of the first tab and its base are unconstrained.
1. A system for deploying a prosthetic valve, said system comprising:
a prosthetic cardiac valve comprising an atrial skirt, a ventricular skirt, and a tab coupled to the ventricular skirt; and
a delivery system comprising an outer sheath, wherein the prosthetic cardiac valve is carried by the delivery system,
wherein partial retraction of the outer sheath releases a constraint from the atrial skirt and the ventricular skirt thereby allowing self-expansion thereof,
wherein further retraction of the outer sheath releases a constraint from the tab, and
wherein a base portion of the tab self-expands radially outward when the constraint is released therefrom.
2. A method for anchoring a prosthetic valve to a cardiac valve having a native valve leaflet, said method comprising:
providing a delivery system having an outer sheath,
providing a prosthetic valve;
the delivery system carrying the prosthetic valve, and the valve comprises an atrial skirt, a ventricular skirt and a first tab coupled to the ventricle skirt;
partially retracting the outer sheath to release a constraint from the atrial skirt, and the ventricular skirt thereby allowing self-expansion thereof; and
further retracting the outer sheath to release a constraint from the tab and to form a leaflet receptacle from an outer surface of the atrial skirt, an outer surface of the ventricular skirt, and an inner surface of the first tab.
3. A method for anchoring a prosthetic valve to a cardiac valve having a valve leaflet, said method comprising:
providing a delivery system having an outer sheath;
providing a prosthetic valve, wherein the prosthetic valve is carried by the delivery system, and wherein the prosthetic valve comprises an atrial skirt, a ventricular skirt and a first tab coupled to the ventricular skirt, and
wherein an outer surface of the atrial skirt, an outer surface of the ventricular skirt, and an inner surface of the first tab forms a leaflet receptacle, the leaflet receptacle having a window for receiving the valve leaflet defined by a gap between an edge of the atrial skirt and a tip of the first tab;
positioning the prosthetic valve adjacent the cardiac valve;
self-expanding the atrial skirt into engagement with an atrial surface of the cardiac valve;
self-expanding the ventricular skirt into engagement with a ventricular surface of the cardiac valve;
removing a constraint from a portion of the first tab thereby allowing a tip of the first tab to expand radially outward;
receiving the valve leaflet through the window and into the leaflet receptacle; and
at least partially closing the window thereby engaging the valve leaflet with the leaflet receptacle and anchoring the prosthetic valve to the valve leaflet.
4. The method of claim 3 , wherein positioning the prosthetic valve adjacent the cardiac valve comprises transseptally delivering the prosthetic valve to the cardiac valve.
5. The method of claim 3 , wherein positioning the prosthetic valve adjacent the cardiac valve comprises transapically delivering the prosthetic valve to the cardiac valve.
6. The method of claim 3 , wherein self-expanding the atrial skirt comprises retracting the outer sheath thereby removing a constraint therefrom.
7. The method of claim 3 , wherein self-expanding the atrial skirt comprises forming a flange which engages an atrial surface of the cardiac valve thereby anchoring the prosthetic valve thereagainst.
8. The method of claim 3 , wherein self-expanding the ventricular skirt comprises retracting the outer sheath thereby removing a constraint therefrom.
9. The method of claim 3 , wherein self-expanding the ventricular skirt comprises expanding the ventricular skirt into engagement with a ventricular surface of the cardiac valve thereby anchoring the prosthetic valve thereagainst.
10. The method of claim 3 , wherein removing a constraint from a portion of the first tab comprises retracting the outer sheath therefrom.
11. The method of claim 3 , wherein at least partially closing the window comprises further retracting the outer sheath to remove a constraint from a base of the first tab thereby allowing the base to radially expand outward and such that the tip of the first tab moves toward the edge of the atrial skirt.
12. The method of claim 3 , wherein the valve leaflet comprises an anterior mitral valve leaflet, the method further comprising engaging the tip of the first tab with a fibrous trigone of the mitral valve.
13. The method of claim 3 , wherein the valve leaflet comprises a posterior mitral valve leaflet, and wherein engaging the valve leaflet comprises engaging the posterior mitral valve leaflet.
14. The method of claim 3 , wherein the atrial skirt expands before the first tab.
15. The method of claim 3 , wherein the atrial skirt anchors the prosthetic valve to the atrium before the first tab anchors the prosthetic valve to the valve leaflet.
16. The method of claim 3 , wherein the first tab expands to a position transverse to a longitudinal axis of the prosthetic valve followed by expansion to a position substantially parallel to the longitudinal axis of the prosthetic valve.