STENT-VALVE AND DEPLOYMENT CATHETER FOR USE THEREWITH

摘要

An improved stent-valve device includes a non-collapsible valve component and a stent component having a first ring connected to a second ring. The first ring has a characteristic first diameter and a valve support for supporting the valve component. The second ring is contractible and expandable between a second diameter less than a third diameter. The second diameter is less than the first diameter and the third diameter is greater than the first diameter. The first ring preferably includes a plurality of elements that extend downward to feet that project radially inward. The valve component rests on the feet for support. A seal is preferably disposed about the first ring. A plurality of suspension elements preferably connect the first ring to the second ring to thereby allow the first ring to hang below the second ring in use. The second ring preferably comprises a band of hexagonal elements having upper apices and lower apices that extend radially outward in a manner that fixates the stent-valve device in place against an inner wall of a blood vessel. The stent component is preferably realized from at least one shape memory metal. The non-collapsible valve component preferably comprises a substantially rigid annular base and a plurality of flexible leaflets that extend from its base. The valve component may be mechanical valve prosthesis, a bio-prosthesis (such as a non- collapsible porcine valve) or a polymer-based prosthesis. In another aspect of the invention, a deployment catheter is provided for effectively deploying the stent-valve device(s) described herein. The deployment catheter includes a first housing that is adapted to store the second ring in its contracted state, and a first body member for axial movement of the first housing relative to the second ring for deployment of the second ring therefrom. A restrictor member is operably disposed adjacent the second ring. The restrictor member is adapted to limit axial movement of the second ring while the first body member is moved axially to deploy the second ring. A second body member, preferably concentric over the first body member, is operably coupled to the restrictor member and is manipulated to effectuate axial movement of the first housing relative to the restrictor member. The deployment catheter preferably includes a second housing that extends through the valve component. The second housing is retracted thereform after deploying the second ring. A third body member, preferably concentric over the first and second body members, is manipulated to effectuate axial movement of the second housing relative to the restrictor and the first housing.