Prosthetic valve that permits retrograde flow
A prosthetic valve for regulating fluid flow through a body vessel is provided. The valve includes an expandable support frame and a valve leaflet, and includes at least one opening that permits a controlled amount of retrograde flow through the valve when the valve is in a closed configuration. A flap disposed adjacent the opening is able to temporarily and substantially close the opening to contribute to the regulation of retrograde flow proceeding through the valve.
1. An implantable medical device that provides a valve for regulating fluid flow through a body vessel, comprising:
a support frame;
at least one leaflet attached to the support frame and being moveable between a first position that permits said fluid flow in a first direction and a second position that substantially prevents said fluid flow in a second, opposite direction, one of the at least one leaflet having a leaflet free edge not attached to the support frame, first and second opposing surfaces and defining an opening extending through the one leaflet from the first surface to the second opposing surface that permits a controlled amount of fluid flow in the second, opposite direction to proceed through the opening when the one leaflet is in the second position, the opening spaced from the leaflet free edge on the one leaflet and having an opening first side edge defined by the one leaflet and an opening second side edge defined by the one leaflet and disposed on the one leaflet opposite the opening first side edge;
a moveable flap integrally formed with a portion of the one leaflet adjacent the opening first side edge and free of the one leaflet at the opening second side edge, the moveable flap adapted to temporarily and substantially close the opening.
2. The implantable medical device according to claim 1 , wherein the at least one leaflet is formed of a bioremodellable material.
3. The implantable medical device according to claim 2 , wherein the bioremodellable material comprises an extracellular matrix material.
4. The implantable medical device according to claim 3 , wherein the bioremodellable material comprises small intestine submucosa.
5. The implantable medical device according to claim 1 , wherein the opening has a total open area; and
wherein the total open area of the opening is sized to be less than the cross-sectional area of said body vessel at a desired point of treatment in said body vessel.
6. The implantable medical device according to claim 1 , wherein the opening has a total open area; and
wherein the total open area of the opening is sized to be less than about 50% of the cross-sectional area of said body vessel at a desired point of treatment in said body vessel.
7. The implantable medical device according to claim 1 , wherein the opening has a total open area; and
wherein the total open area of the opening is sized to be less than about 25% of the cross-sectional area of said body vessel at a desired point of treatment.