SYNTHETIC INFERIOR VENA CAVA GRAFTS. INFLUENCE OF INCREASED FLOW

Prosthetic replacement of the inferior vena cava after resection of a pheochromocytoma

A 52-year-old man had an extensive right adrenal pheochromocytoma with invasion of the pararenal inferior vena cava (IVC). Tumor resection required en bloc resection of the infrahepatic IVC. The right kidney was not involved with tumor. Reconstruction of the IVC was performed with an externally supported, expanded polytetrafluoroethylene graft with reimplantation of the right renal veins into the prosthesis. Postoperative patency of the IVC graft and renal veins was confirmed by venacavography and color-flow duplex scanning. This latter technique has been used to document interval patency of the IVC graft 3, 6, and 12 months after surgery.

Experimental studies of the porosity of the alloplastic vein replacement

The vena cava inferior was replaced by alloplastic vein replacement materials in 60 beagle dogs divided in 6 groups. The wall-porosity varied from 50 to 280 ml/cm2 per minute in the textile prostheses (water porosity) (Groups 1-3), and from 30 to 60 micron fibril length in the expanded PTFE-prostheses. All textile prostheses (woven or knitted) are clearly inferior of expanded PTFE-prostheses. The fibril length of 60 micron represents an improvement in comparison with a length of 30 micron regarding the patency rate and the incorporation process, but it needs a special external support.

A-V fistula after venous reconstruction. A simplified method of producing and obliterating the shunt

To improve patency of the low flow, low pressure crossover venous graft for unilateral iliac venous occlusions, complementary arteriovenous fistula has been effective. Two additional anastomoses are usually required to construct a complementary A-V fistula, and a sometimes difficult and potentially dangerous dissection may be required to take down the fistula. A technique has been developed for producing an A-V fistula with only one additional anastomosis. This fistula can be obliterated later by tightening a previously placed loop left in a subcutaneous position. This technique has been used successfully in two patients.

Adjunctive arteriovenous fistula with tibial and peroneal reconstruction for limb salvage

Arteriovenous fistulas were constructed as an adjunct to femoral peroneal and tibial bypasses in 13 patients threatened by imminent limb amputation. Previous attempts at conventional vascular reconstructive procedures had failed in nine patients. Deficient or absent pedal arches were noted in all patients, as were poor quality or small crural arteries. Graft patency was achieved in 11 cases and limb salvage in 10. There was no mortality. A steal phenomenon occurred in one patient and was successfully treated by secondary popliteal vein ligation. These preliminary results clearly indicate that an adjunctive arteriovenous fistula can maintain patency in a femoral tibial or peroneal bypass graft while preserving flow into the markedly diseased distal circulation.

Autogenous fresh and "matured" fascia as a vascular replacement

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Replacement of large veins with free inverted segments of small bowel: autografts of submucosal membrane in dogs and clinical use

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