Vascular implant and delivery system
A vascular implant for replacing a native heart valve comprises a self expanding stent supporting a valve body having leaflets. The stent preferably comprises an anchoring structure configured to prevent the implant from passing through the valve annulus. For delivery, the implant is compacted within a delivery device and secured at one end. During delivery the implant is partially released from the delivery device, and positioning of the implant can be verified prior to full release. The implant can be at least partially resheathed and repositioned if desired.
1. A method of delivering a replacement valve to a native mitral valve and securing the replacement valve relative to a native mitral valve annulus, the native mitral valve positioned between a left atrium and a left ventricle, the method comprising:
delivering a replacement valve mounted on or within a delivery device to the native mitral valve annulus while the replacement valve is in a radially compacted state, the replacement valve comprising a radially expandable frame extending along a longitudinal axis between a first end and a second end and a plurality of first anchors extending from the frame;
positioning the replacement valve so that the plurality of first anchors are on a ventricular side of the native mitral valve annulus;
releasing a portion of the replacement valve from the delivery device so that the portion of the replacement valve at least partially radially expands and the plurality of first anchors are positioned radially from the delivery device on the ventricular side of the native mitral valve annulus while extending outwardly from the frame in a direction generally pointing towards the left atrium;
after the plurality of first anchors are positioned radially from the delivery device on the ventricular side of the native mitral valve annulus, moving the replacement valve axially toward the native mitral valve so that the plurality of first anchors engage tissue on a ventricular side of the native mitral valve annulus; and
with the plurality of first anchors engaging tissue on the ventricular side of the native mitral valve annulus, further releasing the replacement valve from the delivery device and expanding the frame to a radially expanded state.
2. The method of claim 1 , wherein engaging tissue on the ventricular side of the native mitral valve annulus further comprises engaging the ventricular side of the native mitral valve annulus with the plurality of first anchors.
3. The method of claim 2 , wherein the replacement valve comprises a plurality of second anchors and the method further comprises engaging tissue on an atrial side of the native mitral valve annulus with the plurality of second anchors extending from the frame.
4. The method of claim 3 , wherein expanding the frame to a radially expanded state further comprises drawing respective ends of the plurality of first anchors and the plurality of second anchors closer together to grasp tissue there between.
5. The method of claim 1 , wherein the replacement valve comprises a valve body attached to the radially expandable frame.
6. The method of claim 1 , wherein the frame at least partially radially expands by self-expansion.
7. The method of claim 1 , wherein the replacement valve is released at a native mitral valve annulus without removing the native leaflets.
8. The method of claim 1 , wherein releasing a portion of the replacement valve from the delivery device further comprises releasing a distal portion of the replacement valve from the delivery device while a proximal portion of the replacement valve remains radially compacted.
9. The method of claim 8 , wherein releasing a distal portion of the replacement valve from the delivery device comprises retracting an outer sheath relative to the replacement valve, wherein the retraction exposes the plurality of first anchors and causes the plurality of first anchors to be positioned radially from the delivery device.
10. The method of claim 9 , wherein moving the replacement valve toward the native mitral valve further comprises moving the replacement valve toward the native mitral valve with the proximal portion of the replacement valve covered by the outer sheath.
11. The method of claim 10 , wherein further releasing the replacement valve from the delivery device comprises retracting the outer sheath proximally to expose the proximal portion of the replacement valve.
12. The method of claim 1 , wherein moving the replacement valve toward the native mitral valve comprises moving the entire replacement valve closer to the left atrium after releasing the portion of the replacement valve from the delivery device.
13. The method of claim 1 , wherein after further releasing the replacement valve from the delivery device and expanding the frame to a radially expanded state, the plurality of first anchors are positioned radially outward from the frame and extend in a direction substantially parallel with the longitudinal axis.