DELIVERY SYSTEM FOR REPLACEMENT HEART VALVE
Devices, systems and methods are described herein a prosthesis for implantation within a lumen or body cavity and delivery systems for delivering the prosthesis to a location for implantation. A delivery system can include a plurality of components, including a flexible nose cone, multi-layer sheath, and pre-compressed shaft, which can be moveable relative to each other.
1 . A transseptal delivery system for replacement heart valve implantation, the delivery system comprising:
a nose cone shaft having a proximal end and a distal end and a lumen extending therethrough;
a nose cone provided on the distal end of the nose cone shaft;
an inner retention shaft slideably positioned over the nose cone shaft, the inner retention shaft having a proximal end and a distal end;
an inner retention ring provided on the distal end of the inner retention shaft, the inner retention ring configured to receive struts at a proximal portion of a replacement heart valve prosthesis;
a mid shaft slideably positioned over the inner retention shaft, the mid shaft having a proximal end and a distal end;
an outer retention ring provided on the distal end of the mid shaft, the outer retention ring configured to be positioned over the inner retention ring to hold the proximal portion of the replacement heart valve prosthesis within the inner retention ring; and
an outer sheath assembly slideably positioned over the mid shaft and over the outer retention ring, the outer sheath assembly configured to radially restrain a distal portion of the replacement heart valve prosthesis when the proximal portion of the replacement heart valve prosthesis is held by the outer retention ring within the inner retention ring,
wherein the outer sheath assembly comprises a proximal segment and a distal segment,
wherein the distal segment is configured to cover the replacement heart valve prosthesis, and
wherein the distal segment is formed from an inner polymer layer and an outer polymer layer.
2 . The transseptal delivery system of claim 1 , wherein the outer sheath assembly is configured to slide over the nose cone.
3 . The transseptal delivery system of claim 1 , wherein the distal segment further comprises:
a proximal section comprising a hypotube sandwiched between the inner and outer polymer layers; and
a distal section comprising an intermediate polymer layer sandwiched between the inner and outer polymer layers.
4 . The transseptal delivery system of claim 3 , wherein the distal section has a greater diameter than the proximal section.
5 . The transseptal delivery system of claim 3 , further comprising a polymer reinforcement in the distal section that at least partially overlaps the intermediate polymer layer.
6 . The transseptal delivery system of claim 3 , wherein the inner polymer layer and the outer polymer layer comprise ePTFE with generally longitudinally extending polymer chains, and the intermediate polymer layer comprises ePTFE having generally circumferentially extending polymer chains.
7 . The transseptal delivery system of claim 3 , wherein the hypotube comprises a plurality of circumferentially extending cuts along a longitudinal length thereof
8 . The transseptal delivery system of claim 1 , wherein the mid shaft comprises a longitudinally pre-compressed polymer tube located within the outer sheath assembly, wherein the pre-compressed polymer tube is configured so that deflection of the mid shaft does not substantially change the location of the outer retention ring relative to the inner retention ring.
9 . The transseptal delivery system of claim 1 , wherein the nose cone comprises an elongate hollow body that is distally tapered to facilitate bending of the nose cone when the nose cone is delivered over a guidewire and comes into contact with an internal body surface.
10 . A flexible delivery system for replacement heart valve implantation, the delivery system comprising:
an outer sheath comprising a distal segment configured to cover a replacement heart valve, wherein the distal segment is formed from an inner polymer wall and an outer polymer wall, and wherein the distal segment further comprises:
a proximal section comprising a hypotube sandwiched between the inner polymer wall and the outer polymer wall; and
a distal section comprising an intermediate polymer layer sandwiched between the inner polymer wall and the outer polymer wall.
11 . The delivery system of claim 10 , wherein a proximalmost end of the intermediate polymer layer is distal from a distal most end of the hypotube
12 . The delivery system of claim 10 , wherein the distal section has a greater diameter than the proximal section.
13 . The delivery system of claim 10 , wherein the inner polymer wall, the outer polymer wall, and the intermediate polymer layer comprise ePTFE.
14 . The delivery system of claim 10 , further comprising a polymer reinforcement in the distal section that at least partially overlaps the intermediate polymer layer.
15 . The delivery system of claim 14 , wherein the polymer reinforcement comprises a fluorinated ethylene propylene insert.
16 . The delivery system of claim 10 , further comprising a replacement heart valve loaded within the distal section of the distal segment, wherein the replacement heart valve comprises ventricular anchors that apply a radially outward force to the distal section of the distal segment.
17 . A flexible delivery system for replacement heart valve implantation, the delivery system comprising:
an outer sheath comprising a proximal segment and a distal segment,
wherein the distal segment is configured to cover a replacement heart valve,
wherein the distal segment is formed from two or more layers,
wherein the two or more layers comprise an inner layer, an outer layer, and one or more intermediate layers positioned between the inner and outer layers, and
wherein the one or more intermediate layers comprises a nitinol hypotube.
18 . The flexible delivery system of claim 17 , wherein the inner layer comprises ePTFE.
19 . The flexible delivery system of claim 17 , wherein the outer layer comprises ePTFE.
20 . The flexible delivery system of claim 17 , wherein the distal segment comprises a proximal portion and a distal portion, wherein the proximal portion comprises a first intermediate layer of the one or more intermediate layers and the distal portion comprises a second intermediate layer of the one or more intermediate layers located distal to the first intermediate layer, and wherein a gap exists between the first intermediate layer and the second intermediate layer.