Experimental studies of a nonwoven vascular prosthesis for use in small arteries

Abstract

We have developed a nonporous, 3‐layered laminated vascular prosthesis made of a new nonwoven cloth. Examination of its physical properties and stress relaxation curve showed that the new prosthesis is strong enough to be used as a vascular substitute and compares favorably with human arteries. Animal experiments showed that the nonporosity of the prosthesis did not adversely affect neointima formation. The prosthesis was implanted in the abdominal aorta of 70 dogs for up to 6 years and had a patency rate of 94.3%. The grafts remained elastic and pliable without aneurysmal dilatation even after prolonged use. Studies using light microscopy and scanning electron microscopy showed that a thin, smooth neointima was formed on the inner surface of the prosthesis. The velourlike surface structure of the nonwoven cloth appeared to form a good foundation for deposition of fibrin and formation of the neointima. On the basis of our encouraging experimental results, we have used the new prosthesis for reconstruction of the peripheral arteries in 10 patients, but the followup period has been too short for proper evaluation.