Tethers For Prosthetic Mitral Valve

Abstract

This invention relates to the design and function of a single-tether compressible valve replacement prosthesis which can be deployed into a beating heart without extracorporeal circulation using a transcatheter delivery system. The design as discussed combats the process of wear on anchoring tethers over time by using a plurality of stent-attached, centering tethers, which are themselves attached to a single anchoring tether, which extends through the ventricle and is anchored to a securing device located on the epicardium.

What is claimed is: 
     
         1 . A system for tethering a prosthetic heart valve comprising a transcatheter prosthetic heart valve, wherein the transcatheter prosthetic heart valve comprises:
 an expandable stent having a cuff comprised of wire covered with stabilized tissue or synthetic material, wherein the cuff is positioned with the stent at a first end of the stent, wherein a second end of the stent comprises a tether nexus structure and a first end of a single anchoring tether is attached to the tether nexus structure;   an expandable internal leaflet assembly disposed within the stent and comprised of stabilized tissue or synthetic material; and   a tether securing device including at least one laterally extending pin hole and a pin configured to be received within the pin hole, the tether securing device configured to receive the single anchoring tether and to secure a second end of the single anchoring tether by piercing the single anchoring tether with a first end of the pin so that an entirety of the pin is positioned within the pin hole, the pin having a second free end opposite the first end.   
     
     
         2 . The system 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 system of  claim 1 , further comprising wherein the tether nexus structure is comprised of two or more tethers emanating from the second end of the stent. 
     
     
         4 . The system of  claim 1 , further comprising wherein the individual tethers of the tether nexus structure are braided together at a central point to form the single anchoring tether. 
     
     
         5 . The system of  claim 1 , wherein the tether securing device is located on the apical region of the epicardium. 
     
     
         6 . The system of  claim 1 , wherein the single anchoring tether is comprised of braided filaments and the pins are configured to pierce through the braided filaments. 
     
     
         7 . The system of  claim 1 , wherein the prosthetic heart valve is tethered to the apex of the left ventricle using an interlocking tethering system comprised of a stent-based component and a single-tether distal component that cooperatively engages with the stent-based component to form a secure attachment of the prosthetic heart valve to the apex, and a single-tether proximal component that comprises or attaches to an epicardial tether securing device. 
     
     
         8 . The system  claim 1 , wherein the stent and tethers are formed from the same piece of superelastic or shape-memory metal. 
     
     
         9 . The system of  claim 8 , wherein the metal is a nickel-titanium alloy. 
     
     
         10 . The system of  claim 1 , wherein the tethers are comprised of elastic or any known polymer filament. 
     
     
         11 . The system of  claim 1 , wherein the stent and tethers are laser cut with pre-determined shapes to facilitate collapsing into a catheter delivery system. 
     
     
         12 . The system of  claim 1 , wherein the stabilized tissue of the cuff or leaflet assembly is derived from 30 day old bovine, ovine, equine or porcine pericardium, or from animal small intestine submucosa. 
     
     
         13 . The system of  claim 1 , wherein the synthetic material of the cuff or leaflet assembly is selected from the group consisting of polyester, polyurethane, and polytetrafluoroethylene. 
     
     
         14 . The system of  claim 1 , wherein the stabilized tissue or synthetic material of the cuff or leaflet assembly is treated with anticoagulant.