Abstract
The invention relates to a composite vascular prosthesis, in particular for a flow rate below 100 ml/min and an inner diameter of less than 6 mm, which comprises a non-absorbable layer (2) of knitted fabric which has on the inside and outside a collagen mass of fish collagen of freshwater fish. The non-absorbable layer (2) of knitted fabric is preferably placed on a self-supporting inner absorbable layer (1) of collagen mass, the non-absorbable layer (2) is covered by an intermediate layer of collagen mass on which the outer absorbable layer (3) of collagen mass is located.
It also includes a process for producing this vascular prosthesis, in which a collagen mass with a concentration of 4 to 12% by weight of the collagen is tempered for 18 to 30 hours at a temperature of 15 to 30 °C, after which the non-absorbable layer (2) of knitted fabric is integrated into one layer of the collagen mass to form a coating of collagen mass on the inside and outside of the non-absorbable layer (2) of knitted fabric or collagen. mass with a concentration of 4 to 12% by weight of the collagen is tempered for 18 to 30 hours at a temperature of 15 to 30 °C, after which the inner absorbable layer (1) is extruded from the collagen mass as a tube, which is dried at room temperature to a supple state, then threaded onto the inner absorbable layer (1). a non-absorbable layer (2) of knitted fabric, on which an outer absorbable layer (3) of collagen mass with a concentration of 3 to 12% by weight is extruded. The collagen and vascular prostheses are dried at 15 to 30 °C for 15 to 30 hours until smooth, after which the vascular prostheses are cured with 1.5 to 3.2% resin for 3 to 10 minutes and then dried and softened in a bath of 15 to 30% glycerin for 15 to 25 minutes.