Six-year prospective multicenter randomized comparison of autologous saphenous vein and expanded polytetrafluoroethylene grafts in infrainguinal arterial reconstructions.

Autologous saphenous vein (ASV) and polytetrafluoroethylene (PTFE) grafts were compared in 845 infrainguinal bypass operations, 485 to the popliteal artery and 360 to infrapopliteal arteries. Life-table primary patency rates for randomized PTFE grafts to the popliteal artery paralleled those for randomized ASV grafts to the same level for 2 years and then became significantly different (4-year patency rate of 68% +/- 8% [SE] for ASV vs. 47% +/- 9% for PTFE, p less than 0.025). Four-year patency differences for randomized above-knee grafts were not statistically significant (61% +/- 12% for ASV vs. 38% +/- 13% for PTFE, p greater than 0.25) but were for randomized below-knee grafts (76% +/- 9% for ASV vs. 54% +/- 11% for PTFE, p less than 0.05). Four-year limb salvage rates after bypasses to the popliteal artery to control critical ischemia did not differ for the two types of randomized grafts (75% +/- 10% for ASV vs. 70% +/- 10% for PTFE, p greater than 0.25). Although primary patency rates for randomized and obligatory PTFE grafts to the popliteal artery were significantly different (p less than 0.025), 4-year limb salvage rates were not (70% +/- 10% vs. 68% +/- 20%, p greater than 0.25). Primary patency rates at 4 years for infrapopliteal bypasses with randomized ASV were significantly better than those with randomized PTFE (49% +/- 10% vs. 12% +/- 7%, p less than 0.001). Limb salvage rates at 3 1/2 years for infrapopliteal bypasses with both randomized grafts (57% +/- 10% for ASV and 61% +/- 10% for PTFE) were better than those for obligatory infrapopliteal PTFE grafts (38% +/- 11%, p less than 0.01). These results fail to support the routine preferential use of PTFE grafts for either femoropopliteal or more distal bypasses. However, this graft may be used preferentially in selected poor-risk patients for femoropopliteal bypasses, particularly those that do not cross the knee. Although every effort should be made to use ASV for infrapopliteal bypasses, a PTFE distal bypass is a better option than a primary major amputation.

Lessons learned in adopting the in situ saphenous vein bypass.

A 3-year experience with in situ saphenous vein bypasses was analyzed to evaluate the suitability of the conduit, the effect on vein utilization rate, the ease of valve ablation, the incidence of persistent arteriovenous (AV) fistula, the duration of the operation, and the nature of the learning curve to become adept at this technique. From 1981 through 1983, 74 patients underwent 55 femoral-tibial and 23 femoral-popliteal in situ saphenous vein bypasses. The operative indications were threatened limb loss in 76 (97%) and disabling claudication in 2 (3%); 35 of 74 patients (48%) were diabetic. In the last year pulsed Doppler spectrum analysis was added to arteriography for intraoperative graft assessment. For 55 femoral-tibial grafts measured by life-table patency rates at 30 days, only one femoral-popliteal graft failed (1 1/2 years). Complete vein utilization was accomplished in 91% of the bypasses attempted. In 41 of the 78 (51%) grafts, vein diameter was 3.5 mm or less. Operative time decreased with experience. Pulsed Doppler spectral analysis has proved useful for intraoperative graft evaluation. The in situ saphenous vein has become the conduit of choice for infrageniculate bypass.