Rotation-based anchoring of an implant
Apparatus is provided for use at a native atrioventricular valve of a heart of a subject. A prosthetic valve structure includes prosthetic leaflets configured to facilitate upstream-to-downstream bloodflow longitudinally through the prosthetic valve structure. The apparatus includes an annular portion configured to be positioned at the native atrioventricular valve and curved anchors that point in a circumferential direction around the annular portion. The anchors each having a leading tip configured to gather chordae tendineae of the heart between the anchors and the annular portion. Rotation of the prosthetic valve structure in the circumferential direction causes the anchors to gather the chordae tendineae between the anchors and the annular portion by the anchors moving, leading tip first, in the circumferential direction. Other embodiments are also described.
1. Apparatus for use at a native atrioventricular valve of a heart of a subject, the apparatus comprising a prosthetic valve structure that comprises:
prosthetic leaflets configured to facilitate upstream-to-downstream bloodflow longitudinally through the prosthetic valve structure;
an annular portion configured to be positioned at the native atrioventricular valve; and
curved anchors that point in a circumferential direction around the annular portion, the anchors each having a leading tip and being configured to gather chordae tendineae of the heart between the anchors and the annular portion upon rotation of the prosthetic valve structure in the circumferential direction in a manner that causes the anchors to gather the chordae tendineae between the anchors and the annular portion by the anchors moving, leading tip first, in the circumferential direction.
2. The apparatus according to claim 1 , wherein the anchors are disposed circumferentially around the annular portion.
3. The apparatus according to claim 1 , wherein each of the anchors defines a base portion coupled to the annular portion, and wherein the anchor is tapered progressing in a direction from the base portion toward the leading tip.
4. The apparatus according to claim 3 , wherein each of the anchors extends away from the annular portion and turns such that the leading tip of the anchor points in the circumferential direction.
5. The apparatus according to claim 3 , wherein each of the anchors bends almost 90 degrees progressing in the direction from the base portion toward the leading tip.
6. The apparatus according to claim 1 , wherein each of the anchors defines a portion that extends radially outward from the annular portion such that a space is defined between the anchor and the annular portion.
7. The apparatus according to claim 6 , wherein each of the anchors curves circumferentially between the portion that extends radially and the leading tip.
8. The apparatus according to claim 1 , wherein the prosthetic valve structure comprises 4-8 of the anchors.
9. The apparatus according to claim 8 , wherein the prosthetic valve structure comprises six of the anchors.
10. The apparatus according to claim 1 , wherein the apparatus comprises, at a ventricular end of the apparatus, (a) a flexible frame and (b) a fabric surrounding a lumen of the prosthetic valve structure and held by the frame between the frame and the annular portion.
11. The apparatus according to claim 10 , wherein the frame is continuous.
12. The apparatus according to claim 10 , wherein the frame is arranged in an undulating pattern.
13. The apparatus according to claim 10 , wherein the frame is shaped so as to define a plurality of ascending portions and descending portions, distributed circumferentially around the lumen.
14. The apparatus according to claim 10 , wherein the frame is shaped so as to define a plurality of petals, each petal having an ascending portion and a descending portion.
15. The apparatus according to claim 14 , wherein the frame is shaped so as to define five of the petals.
16. The apparatus according to claim 1 , wherein:
in a collapsed state of the prosthetic valve structure, the leading tips of the anchors are at a first position which is at a first axial level measured along a central longitudinal axis of the prosthetic valve structure,
in an expanded state of the prosthetic valve structure, the leading tips of the anchors are at a second position which is at a second axial level measured along the central longitudinal axis of the prosthetic valve structure, and
the second axial level is lower than the first axial level.