Methods for regulating the flow of blood through the blood system
A valve prosthesis is disclosed which is implantable within a vein or other blood vessel of a patient using a minimally-invasive surgical procedure. The prosthesis includes a tubular wire frame which presses radially outward against the inner walls of the blood vessel following implantation to hold the prosthesis in position. Multiple flow-resistive pockets that open and close in response to changes in blood flow direction are attached to the frame to impede the flow of blood in the reverse direction. The prosthesis is implanted using an introducer catheter which holds the prosthesis in a radially-compressed state as the prosthesis is inserted into and positioned within the blood vessel.
1. A minimally invasive method of implanting a valve prosthesis device comprising a plurality of flexible, conical blood flow stoppage elements, each having a memory metal frame within an existing vein of a human to restore venous valvular function within the vein, the plurality of flexible, conical blood flow stoppage elements, each having a memory metal frame adapted to press outward against the inner walls of the vein to hold the plurality of flexible, conical blood flow stoppage elements, each having a memory metal frame in position within the vein following implantation, the method comprising the steps of:
collapsing the flexible, conical blood flow stoppage elements;
overlapping flareable proximal ends of the flexible, conical blood flow stoppage elements;
positioning the collapsed plurality of flexible, conical blood flow stoppage elements, each having a memory metal frame within a hollow distal portion of an introducer with the plurality of flexible, conical blood flow stoppage elements, each having a memory metal frame in a compressed state;
advancing the hollow distal portion of the introducer, with the plurality of flexible, conical blood flow stoppage elements, each having a memory metal frame positioned therein, into the vein of the human through an opening in a wall of the vein;
expelling the plurality of flexible, conical blood flow stoppage elements, each having a memory metal frame from the hollow distal portion of the introducer into the vein; and
temperature expanding the plurality of flexible, conical blood flow stoppage element frames, and thereby expanding the flareable proximal ends of the blow flow stoppage elements such that they no longer overlap as so to expand to an operational state in which the plurality of flexible, conical blood flow stoppage elements, each having a memory metal frame are maintained in position within the vein by pressing outward against the inner walls of the vein.
2. The method of claim 1 , wherein the step of expelling comprises slidably advancing an expulsion member distally within the introducer to forcibly displace the plurality of flexible, conical blood flow stoppage elements, each having a memory metal frame from the hollow distal portion of the introducer.
3. The method of claim 1 , wherein the plurality of flexible, conical blood flow stoppage elements and memory metal frames is rollable upon itself to place the frames in a tubular configuration, and wherein the step of positioning comprises rolling the frames against a biasing force to place the plurality of flexible, conical blood flow stoppage elements and memory metal frames in a radially-compressed configuration that corresponds to an inner diameter of the hollow distal portion of the introducer.