Composition for use in making prosthetic vascular devices, and prosthetic devices made therefrom

Claim 2

A composition for use in making a prosthetic vascular device, comprising a suitable biologically compatible plastic material having a negative charge.

Claim 3

A composition according to claim 1, which comprises a biologically compatible plastic and a compatible substance having a negative charge.

Claim 4

A composition according to claim 2 wherein the said substance is incorporated into the structure of the plastic.

Claim 5

A composition according to claim 3 wherein the structure is the framework of its lattice.

Claim 6

A composition according to any preceding claim, wherein the plastic is polytetrafluoroethylene.

Claim 7

A composition according to any one of claims 2 to 4, wherein the compound comprises polytetrafluoroethylene and graphite.

Claim 8

A composition according to claim 6, wherein the ratio of polytetrafluoroethylene to graphite by weight, is from 5:1 to 15:1.

Claim 9

A composition according to claim 7, wherein the ratio of polytetrafluoroethylene to graphite by weight, is about 9:1.

Claim 10

A prosthetic vascular device made from the composition of any preceding claim.

Claim 11

A device according to claim 9, which is the form of a prosthetic heart valve leaflet.

Claim 12

A device according to claim 10, wherein the composition comprises expanded polytetrafuloroethylene and graphite, the internodal distances of the polytetrafluoroethylene being in the range of from 1 to 60 u and the average wall thickness being in the range of from 0.2 to 1.5 mm.

Claim 13

A device according to claim 9, which is in the form of a venous prosthetic device.

Claim 14

A device according to claim 9, which is in the form of an arterial prosthetic device.

Claim 15

A device according to claim 9, which is of highly expanded polytetrafluoroethylene having graphite incorporated into the framework of its lattice and having a macroscopically tubular configuration with proximal and distal ends, and a microscopic superstructure of irregularly spaced nodes of various sizes and shapes interconnected by fibrils. The device having an average wall thickness of from 0.2 to 1.5 mm., a substantially uniform distribution of nodes throughout the tubular configuration, an average density of from 0.2 to 0.7 g/ml, and an average distance between the said nodes small enough to prevent transmural blood flow and thrombosis but not less than the approximate dimension of red blood cell, whereby means are provided for smoothly conveying a flow of blood between at least two points in a living organism while ensuring and controlling cellular ingrowth through the wall of the tubular configuration to promote and nourish a thin, viable neointima over the inner surface thereof and to firmly attach the prosthetic vascular structure to adjacent tissue of the living organism.

Claim 16

A device according to claim 14, wherein the said nodes are generally elliposidal in shape and have an average dimension along their minor axes less than three times the maximum dimension of an average red cell.

Claim 17

A device according to claim 15, wherein the major axes of the said nodes are in a generally radial orientation with respect to the tubular configuration.

Claim 18

A device according to claim 14, 15 or 16, wherein the tubular configuration thereof has an average inside diameter of not more than 40 mm.

Claim 19

A device according to claim 17, wherein the tubular configuration thereof has an average inside diameter of less than 8 mm.

Claim 20

A device according to claim 17, wherein the tubular configuration thereof has an average inside diameter of from 2 to 6 mm.

Claim 22

A device according to claim 20, wherein the first inside diameter is from 5 to 8 mm and the second inside diameter is from 2 to 6 mm.

Claim 24

A device according to claim 9, which is of highly expanded polytetrafluoroethylene having graphite included in its structure and having a macroscopically tubular configuration with proximal and distal ends, and a microscopic superstructure of irregularly spaced nodes of various sizes and shapes interconnected by fibrils, the device having an average inside diameter of from 2 to 40 mm, an average wall thickness of from 0.2 to 1.5 mm, a substantially uniform distribution of generally ellipsoidal nodes having major axes disposed in a generally radial orientation with respect to the tubular configuration and an average minor axis dimension less than 18 microns, an average density of from 0.2 and 0.7 g/ml, and a tensile strength of from 175 to 450 kg/cm 2 whereby means are provided for smoothly conveying a flow of blood between at least two points in a living organism while ensuring and controlling cellular ingrowth through the wall of the tubular configuration to promote and nourish a thin, viable neointima over the inner surface thereof and to firmly attach the prosthetic vascular structure to adjacent tissue of the living organism.