EXPERIMENTAL REPAIR OF VENOUS VALVULAR INSUFFICIENCY USING A CRYOPRESERVED VENOUS VALVE ALLOGRAFT AIDED BY A DISTAL ARTERIOVENOUS-FISTULA

Purpose: To evaluate the patency and hemodynamic impact of a cryoprese rved allograft venous valve transplanted to the superficial femoral ve in (SFV) of a canine insufficiency model aided by a distal arterioveno us fistula (dAVF). Methods: Eight greyhounds had intravenous hemodynam ic parameters measured (venous filling time [VFT], 90% of venous refil ling time [VRT90], and simulated ambulatory venous pressure [AVP]) bef ore (T-0) and after complete hindlimb venous valvulotomy (T-1) to prod uce venous insufficiency. Simultaneously, a valve-containing vein segm ent was harvested from the opposite SFV or external jugular vein (n = 1) and cryopreserved. Three weeks later a blood type-matched cryoprese rved valve was transplanted to the insufficient SFV aided by a low-flo w (n = 4) or high-how (n = 4) dAVF. The fistula was ligated in 3 to 6 weeks, and venous indexes (T-2) were obtained 3 weeks later. Analysis of variances compared the venous indexes at T-0, T-1, and T-2 for stat istical significance. Gross and histologic inspection assessed valve i ntegrity. Results: Two valves aided by a low-how dAVF exhibited thromb osis and scarring. The hemodynamics of the six remaining valves demons trated normalization of the VRT90, an AVP consistent with insufficienc y, and a VFT between normal and total venous insufficiency. The patent valves were normal on gross examination and by histologic examination with signs of normal external healing. Conclusions: A cryopreserved v enous valve allograft transplanted to the SFV of an incompetent hindli mb partially corrects venous hemodynamics. A high-how arteriovenous fi stula most consistently preserves transplant patency.