Device and System for Transcatheter Mitral Valve Replacement

Abstract

This invention relates to the design and function of a compressible valve replacement prosthesis which can be deployed into a beating heart without extracorporeal circulation using a transcatheter delivery system. The design as discussed focuses on the deployment of a device via a minimally invasive fashion and by way of example considers a minimally invasive surgical procedure preferably utilizing the intercostal or subxyphoid space for valve introduction. In order to accomplish this, the valve is formed in such a manner that it can be compressed to fit within a delivery system and secondarily ejected from the delivery system into the annulus of a target valve such as a mitral valve or tricuspid valve.

1 . A prosthetic heart valve which comprises an expandable tubular stent having a cuff and an expandable internal leaflet assembly, wherein said cuff is comprised of wire covered with stabilized tissue or synthetic material, and wherein said leaflet assembly is disposed within the stent and is comprised of stabilized tissue or synthetic material. 
     
     
         2 . The prosthetic heart valve of  claim 1 , wherein the prosthetic heart valve is elastic and is compressed into a delivery catheter for deployment within a patient, and whereby upon expelling the prosthetic heart valve from the delivery catheter, the valve expands to its functional shape. 
     
     
         3 . The prosthetic heart valve of  claim 1 , wherein the cuff wire comprises wire from one end of the stent, wherein the cuff wire is formed as a series of radially extending loops. 
     
     
         4 . The prosthetic heart valve of  claim 3 , wherein the radially extending loops of the cuff are made from a superelastic metal and articulate to locally contour to the valve annulus. 
     
     
         5 . The prosthetic heart valve of  claim 4 , wherein one or more of the radially extending loops extend outwardly in various lengths. 
     
     
         6 . The prosthetic heart valve of  claim 4 , wherein the superelastic metal is a nickel-titanium alloy. 
     
     
         7 . The prosthetic heart valve of  claim 1 , wherein the stent and cuff are formed from the same piece of superelastic metal. 
     
     
         8 . The prosthetic heart valve of  claim 7 , wherein the superelastic metal is a nickel-titanium alloy. 
     
     
         9 . The prosthetic heart valve of  claim 7 , wherein the stent and cuff are laser cut with predetermined shapes to facilitate collapsing into a catheter delivery system. 
     
     
         10 . The prosthetic heart valve of  claim 1 , wherein the stent is constructed from ductile metal that requires a balloon for expansion once the valve is positioned at the valve annulus. 
     
     
         11 . The prosthetic heart valve of  claim 1 , wherein the stabilized tissue is derived from 30 day old bovine, ovine, equine or porcine pericardium, or from animal small intestine submucosa. 
     
     
         12 . The prosthetic heart valve of  claim 1 , wherein the synthetic material is selected from the group consisting of polyester, polyurethane, and polytetrafluoroethylene. 
     
     
         13 . The prosthetic heart valve of  claim 1 , wherein the stabilized tissue or synthetic material is treated with anticoagulant. 
     
     
         14 . The prosthetic heart valve of  claim 1 , wherein the stabilized tissue or synthetic material is heparinized. 
     
     
         15 . The prosthetic heart valve of  claim 1 , wherein the angle of the cuff to the stent comprises a range of between about 60 and about 150 degrees. 
     
     
         16 . The prosthetic heart valve of  claim 1 , wherein the ratio of the relationship between the height of the expanded deployed stent (h) and the lateral distance that the cuff extends onto the cardiac tissue ( 1 ) ranges from about 1:10 to about 10:1. 
     
     
         17 . The prosthetic heart valve of  claim 1 , wherein the cuff extends laterally beyond the wall of the expanded tubular stent between about 8 and about 20 millimeters. 
     
     
         18 . The prosthetic heart valve of  claim 1 , wherein the tubular stent has a first end and a second end, wherein the cuff is connected to the tubular stent at the first end of the tubular stent, and the second end of the tubular stent has a plurality of tether attachment structures . 
     
     
         19 . The prosthetic heart valve of  claim 1 , further comprising a plurality of tethers attached to the prosthetic heart valve for anchoring the prosthetic heart valve to tissue. 
     
     
         20 . The prosthetic heart valve of  claim 19 , wherein at least one of the plurality of tethers is an elastic tether. 
     
     
         21 . The prosthetic heart valve of  claim 19 , wherein at least one of the plurality of tethers is a bioresorbable tether. 
     
     
         22 . The prosthetic heart valve of  claim 19 , wherein at least one of the plurality of tethers is a positioning tether and at least one of the plurality of tethers is an anchoring tether. 
     
     
         23 . The prosthetic heart valve of  claim 1 , wherein the cuff is connected to a plurality of tethers. 
     
     
         24 . The prosthetic heart valve of  claim 23 , wherein at least one of the plurality of tethers is an elastic tether. 
     
     
         25 . The prosthetic heart valve of  claim 23 , wherein at least one of the plurality of tethers is a bioresorbable tether. 
     
     
         26 . The prosthetic heart valve of  claim 23 , wherein at least one of the plurality of tethers is a positioning tether and at least one of the plurality of tethers is an anchoring tether. 
     
     
         27 . The prosthetic heart valve of  claim 1 , further comprising at least one tether attached to the cuff and at least one tether attached to the stent body. 
     
     
         28 . The prosthetic heart valve of  claim 27 , wherein at least one of the plurality of tethers is an elastic tether. 
     
     
         29 . The prosthetic heart valve of  claim 27 , wherein at least one of the plurality of tethers is a bioresorbable tether. 
     
     
         30 . The prosthetic heart valve of  claim 27 , wherein at least one of the plurality of tethers is a positioning tether and at least one of the plurality of tethers is an anchoring tether. 
     
     
         31 . The prosthetic heart valve of  claim 1 , further comprising a plurality of tethers attached to the prosthetic heart valve wherein one of the plurality of tethers is attached to an epicardial tether securing device. 
     
     
         32 . The prosthetic heart valve of  claim 31 , wherein at least one of the plurality of tethers is an elastic tether. 
     
     
         33 . The prosthetic heart valve of  claim 31 , wherein at least one of the plurality of tethers is a bioresorbable tether. 
     
     
         34 . The prosthetic heart valve of  claim 1 , further comprising a plurality of anchoring barbs attached to the prosthetic heart valve for anchoring the valve into local tissue. 
     
     
         35 . The prosthetic heart valve of  claim 1 , further comprising a combination of anchoring tethers and anchoring barbs attached to the prosthetic heart valve for anchoring the valve into local tissue. 
     
     
         36 . The prosthetic heart valve of  claim 35 , further comprising at least one positioning tether attached to the prosthetic heart valve. 
     
     
         37 . The prosthetic heart valve of  claim 35 , wherein at least of the anchoring tethers is an elastic tether. 
     
     
         38 . The prosthetic heart valve of  claim 35 , wherein at least one of the anchoring tethers is a bioresorbable tether. 
     
     
         39 . The prosthetic heart valve of  claim 1 , wherein the leaflet assembly is constructed solely of stabilized tissue or synthetic material without a separate wire support structure, wherein the leaflet assembly comprises a plurality of valve leaflets attached to a leaflet housing, wherein the leaflet assembly is disposed within the lumen of the stent and is attached to the stent to provide a sealed joint between the leaflet assembly and the inner wall of the stent. 
     
     
         40 . The prosthetic heart valve of  claim 1 , wherein the leaflet assembly comprises a leaflet wire support structure to which a plurality of valve leaflets are attached and the entire leaflet assembly is housed within the stent body, wherein the leaflets are made from stabilized tissue or synthetic material , wherein the leaflet wire support is made from a superelastic metal, wherein the leaflet assembly is disposed within the lumen of the stent and is attached to the stent to provide a sealed joint between the leaflet assembly and the inner wall of the stent. 
     
     
         41 . The leaflet assembly according to any of  claim 39  or  40 , wherein the leaflet assembly is shaped to have a hyperbolic paraboloid shape defining commissural points. 
     
     
         42 . The leaflet assembly according to  claim 41 , further comprising at least one tether attached to the commissural point of the leaflet assembly, and a plurality of tethers attached to the stent body, the cuff, or both. 
     
     
         43 . A cuff for a prosthetic heart valve wherein the cuff has an articulating structure made of a superelastic metal that is covered with stabilized tissue or synthetic material. 
     
     
         44 . The cuff of  claim 43 , wherein the articulating structure comprises a plurality of radially extending loops. 
     
     
         45 . The cuff of  claim 44 , wherein the radially extending loops extend outwardly in various lengths. 
     
     
         46 . The cuff of  claim 43 , wherein the superelastic metal is a nickel-titanium alloy . 
     
     
         47 . The cuff of  claim 43 , wherein the stabilized tissue is derived from 30 day old bovine, ovine, equine or porcine pericardium, or from animal small intestine submucosa. 
     
     
         48 . The cuff of  claim 43 , wherein the synthetic material is selected from the group consisting of polyester, polyurethane, and polytetrafluoroethylene. 
     
     
         49 . The cuff of  claim 43 , wherein the stabilized tissue or synthetic material is treated with anticoagulant. 
     
     
         50 . The cuff of  claim 43 , wherein the stabilized tissue or synthetic material is heparinized. 
     
     
         51 . A catheter delivery system for delivery of the prosthetic heart valve of  claim 1  which comprises a delivery catheter having the prosthetic heart valve of  claim 1  disposed therein, and an obturator for expelling the prosthetic heart valve. 
     
     
         52 . An assembly kit for preparing the catheter delivery system of  claim 51  that is comprised of a compression funnel, an introducer, a wire snare, an obturator, a delivery catheter, and a prosthetic heart valve of  claim 1 , wherein the compression funnel has an aperture for attaching to the introducer, wherein said introducer is comprised of a tube that fits within the diameter of the delivery catheter, wherein said obturator is comprised of a tube fitted with a handle at one end and an cap at the other end, wherein said cap has an opening to allow the wire snare to travel therethrough, wherein said obturator fits within the diameter of the introducer, and wherein said prosthetic heart valve is compressible and fits within the delivery catheter. 
     
     
         53 . A method of treating mitral regurgitation in a patient, which comprises the step of surgically deploying the prosthetic heart valve of  claim 1  into the mitral annulus of the patient. 
     
     
         54 . The method of  claim 53 , wherein the prosthetic heart valve is deployed by directly accessing the heart through the intercostal space, using an apical approach to enter the left ventricle, and deploying the prosthetic heart valve into the mitral annulus using the catheter delivery system of  claim 51 . 
     
     
         55 . The method of  claim 53 , wherein the prosthetic heart valve is deployed by directly accessing the heart through a thoracotomy, sternotomy, or minimally-invasive thoracic, thorascopic, or trans-diaphragmatic approach to enter the left ventricle. 
     
     
         56 . The method of  claim 53 , wherein the prosthetic heart valve is deployed by directly accessing the heart through the intercostal space, using an approach through the lateral ventricular wall to enter the left ventricle. 
     
     
         57 . The method of  claim 53 , wherein the prosthetic heart valve is deployed by accessing the left atrium of the heart using a transvenous atrial septostomy approach. 
     
     
         58 . The method of  claim 53 , wherein the prosthetic heart valve is deployed by accessing the left ventricle of the heart using a transarterial retrograde aortic valve approach. 
     
     
         59 . The method of  claim 53 , wherein the prosthetic heart valve is deployed by accessing the left ventricle of the heart using a transvenous ventricular septostomy approach. 
     
     
         60 . The method of any of  claims 53 - 59 , further comprising deploying the prosthetic heart valve using the catheter delivery system of  claim 51 . 
     
     
         61 . The method of any of  claims 53 - 59 , further comprising tethering the prosthetic heart valve to tissue within the left ventricle. 
     
     
         62 . The method of any of  claim 53 - 59 , wherein the prosthetic heart valve is tethered to the apex of the left ventricle using an epicardial tether securing device. 
     
     
         63 . The method of  claim 61 , wherein the tissue is selected from papillary muscle tissue, septal tissue, or ventricular wall tissue. 
     
     
         64 . The method of  claim 53 , wherein the prosthetic heart valve is tethered to the apex of the ventricular septum. 
     
     
         65 . A method of treating tricuspid regurgitation in a patient, which comprises the step of surgically deploying the prosthetic heart valve of  claim 1  into the tricuspid annulus of the patient. 
     
     
         66 . The method of  claim 65 , wherein the prosthetic heart valve is deployed by directly accessing the heart through the intercostal space, using an apical approach to enter the right ventricle. 
     
     
         67 . The method of  claim 65 , wherein the prosthetic heart valve is deployed by directly accessing the heart through a thoracotomy, sternotomy, or minimally-invasive thoracic, thorascopic, or trans-diaphragmatic approach to enter the right ventricle. 
     
     
         68 . The method of  claim 65 , wherein the prosthetic heart valve is deployed by directly accessing the heart through the intercostal space, using an approach through the lateral ventricular wall to enter the right ventricle. 
     
     
         69 . The method of  claim 65 , wherein the prosthetic heart valve is deployed by accessing the right atrium of the heart using a transvenous approach. 
     
     
         70 . The method of any of  claims 65 - 69 , further comprising deploying the prosthetic heart valve using the catheter delivery system of  claim 51 . 
     
     
         71 . The method of any of  claims 65 - 69 , further comprising tethering the prosthetic heart valve to tissue within the right ventricle. 
     
     
         72 . The method of any of  claims 65 - 69 , wherein the prosthetic heart valve is tethered to the apex of the right ventricle using an epicardial tether securing device. 
     
     
         73 . The method of  claim 71 , wherein the tissue is selected from papillary muscle tissue, septal tissue, or ventricular wall tissue. 
     
     
         74 . A retrieval method for quickly removing a prosthetic heart valve having one or more tethers from a patient that is comprised of the steps of capturing the one or more tethers with a catheter having a snare attachment, guiding the captured tethers into a collapsible funnel attachment connected to removal catheter, pulling the tethers to conform the prosthetic heart valve into a collapsed, compressed conformation, and pulling the now compressed prosthetic heart valve into the removal catheter for subsequent extraction. 
     
     
         75 . The retrieval method of  claim 74 , wherein the prosthetic heart valve is the prosthetic heart valve of  claim 1 . 
     
     
         76 . The retrieval method of  claim 74 , further comprising the step of removing one or more tether-tissue anchors. 
     
     
         77 . The retrieval method of  claim 74 , wherein the prosthetic heart valve is a prosthetic mitral valve. 
     
     
         78 . The retrieval method of  claim 74 , wherein the prosthetic heart valve is a prosthetic tricuspid valve.