The "all-autogenous" tissue policy for infrainguinal reconstruction questioned

Is color duplex surveillance of infrainguinal polytetrafluoroethylene grafts worthwhile?

BACKGROUND

Unlike vein bypasses, the role of duplex surveillance of infrainguinal prosthetic bypass grafts is controversial. The purpose of this study was to evaluate the adequacy of color duplex surveillance in identifying failing infrainguinal polytetrafluoroethylene (PTFE) bypass grafts and to assess its value in predicting continued bypass patency.

METHOD

The surveillance data of primarily patent PTFE bypass grafts were compared with those of revised/occluded PTFE grafts. Ninety-five patients underwent 102 infrainguinal PTFE bypass grafts from January 1991 to December 1996 and were enrolled in a duplex surveillance program at 1 month postoperatively, every 3 months in the first year, every 6 months in the second year, and yearly thereafter.

RESULTS

Seventy grafts remained primarily patent, 5 were revised and 27 occluded. There was no significant difference in the mean age, gender, indication for surgery, type of original procedure, or duration of follow-up between both groups. Four hundred and seven duplex surveillance data were available for analysis. Focal increase in peak systolic velocity (PSV) 3 x the adjacent segment or low flow manifested by PSV <45 cm/sec were considered abnormal. In the primarily patent group, 5 bypasses had abnormal duplex surveillance and were found to have no abnormality on angiogram and remained patent during the study period. In the revised/occluded group, duplex surveillance was abnormal in 8 bypasses. Twenty-four bypasses occluded without any predicting abnormalities on their last duplex examination, which was performed within 3 months from the occlusion in the majority of the patients. In the 27 occluded bypasses, no intervention was necessary following the occlusion in 7 grafts because of mild or no symptoms. Two patients were treated with a primary amputation and 2 had new bypasses. In 16 occluded grafts, salvage of the PTFE bypass was attempted. Ten of these grafts were patent at the end of the follow-up. The sensitivity of duplex surveillance was 25% with a positive predictive value of 61.5%.

CONCLUSION

Duplex surveillance of infrainguinal PTFE bypass grafts has a low yield and is inadequate at predicting continued bypass patency.

Vascular reconstruction in limb salvage operations for soft tissue tumors of the extremities

Eight patients with vascular threatening soft tissue tumors underwent wide excision of the tumors followed by vascular reconstruction. Superficial femoral vessels were resected in 6 patients and popliteal vessels in 2 patients. Arterial reconstruction was performed with a synthetic graft in 4 and a reversed saphenous vein graft in 4. Venous reconstruction was performed with a synthetic graft in 5 and a saphenous vein graft in 2. Adjuvant multimodality treatment was used in 6 patients. After an average of 30 months, the revascularized vessels were found to be patent in 5 patients with arterial reconstruction and in 1 patient with venous reconstruction. Six patients maintained functional extremities. Two other patients had to have amputations, 1 because of a deep infection that involved the grafts and the other because of an acute occlusion of the reconstructed artery. Edema of the leg, which was treated successfully with an elastic support and elevation of the leg, has been observed in all patients after operation. No local recurrence has been observed with an average followup period of 42.5 months. Pulmonary metastasis developed in 2 patients, and 1 of them underwent a pulmonary metastasectomy. Limb salvage in vascular threatening soft tissue tumors using vascular reconstruction techniques is useful and preferable in some patients.

Repeat leg bypass after multiple prior bypass failures

PURPOSE

The optimal treatment of patients with severe lower extremity ischemia after multiple failed prior bypasses is unclear. It is presently unknown whether failure of attempted revascularization in these patients is so likely that such operation should not be elected. We have maintained an aggressive surgical policy of repeated revascularization regardless of prior failures. A review of our clinical experience with this difficult patient group was performed to determine the results of this policy.

METHODS

From 1980 to 1992, 85 revascularization procedures were performed in 81 patients with lower extremity ischemia after failure of two or more prior infrainguinal bypasses in the same leg. All patients were prospectively entered and monitored in our vascular registry. Seventy-two operations were the third procedure, six operations were the fourth procedure, and seven operations were the fifth procedure on the same extremity. Twenty-six of the 85 procedures (30%) were revisions of failing grafts discovered by routine surveillance methods, whereas 59 were replacements of thrombosed grafts. Autogenous reconstruction was used in 67 procedures (79%), and prosthetic reconstruction was used in 18 procedures (21%). The distal anastomosis was to the popliteal artery in 19 patients and infrapopliteal artery in 66.

RESULTS

Mean time to failure of the first leg bypass was 24 months and 4.9 months for the second bypass. Detailed hematologic screening revealed identifiable hypercoagulable disorders in nine (15%) of 59 patients screened after 1987. All nine had anticardiolipin antibodies. The operative mortality rate was 4%. Mean follow-up after the most recent operation was 17 months. The primary patency rate at 4 years was 79.8%. The limb salvage rate was 69.6% at 4 years.

CONCLUSIONS

These results indicate that limb revascularization after two or more failed leg bypasses results in low operative mortality rates and surprisingly good primary patency and limb salvage rates at 4 years. The patient survival rate through 4 years is unexpectedly high. In our opinion these results justify an aggressive policy of limb vascularization after multiple failed prior bypasses.