Long-term outcome of revised lower-extremity bypass grafts*1

Abstract

Purpose: Reversed lower-extremity vein grafts (LEVGs) frequently require operative revisions to maintain patency. Identifying grafts that are at risk, however, requires an intensive duplex scanning-based surveillance program. Excellent 5-year graft patency and limb-salvage rates have previously been reported in patients undergoing graft revisions, but results beyond 5 years are essentially unknown, a factor that is of importance in an increasingly aging population. This study was performed to determine the results of surgical revisions of LEVGs after a follow-up as long as 10 years. Methods: All patients undergoing placement of a LEVG were observed in a program of duplex scanning-based surveillance as long as the patient remained a candidate for graft revision. Grafts were considered for revision on the basis of the presence of focal areas of increased velocity, a prestenotic to intrastenotic velocity ratio more than 3.0, or uniformly low velocities throughout the graft. All lesions were confirmed with preoperative arteriography before revision. Assisted primary patency, limb-salvage, and survival rates were determined by means of Kaplan-Meier analysis in all patients who underwent LEVG revision from January 1990 to December 2000. Results: A total of 1498 LEVG procedures were performed during the study period. A total of 330 surgical graft revisions were performed on 259 extremities in 245 patients. The median follow-up period was 38 months. The assisted primary patency rate of all grafts, the limb-salvage rate for patients undergoing surgery for limb-salvage indications, and the survival rate of all patients were 87.4%, 88.7%, and 72.4%, respectively, 5 years after the original bypass grafting procedure, 85.7%, 83.4%, and 67.8%, respectively, 7 years after the original bypass grafting procedure, and 80.4%, 75.4%, and 53.4%, respectively, 10 years after the original bypass grafting procedure. A total of 180 revisions (55%) were performed during the first year, 110 (33%) between the first year and the fifth year, and 40 revisions (12%) were performed on grafts older than 5 years. LEVGs revised within the first year after bypass grafting had lesions within the graft in 78%, in the native arterial inflow in 10%, and in the native arterial outflow in 12%. This differed significantly from the location of lesions in revisions performed between 1 and 5 years and after 5 years (graft, 63% and 62%; inflow, 20% and 19%; outflow, 17% and 19%; P >.05, Chi-square). Conclusion: Excellent assisted primary patency and limb-salvage rates can be achieved for as long as 10 years in LEVGs that require revision, with only a 7% drop in overall patency and limb-salvage rates between the fifth and 10th years. Although most revisions were required within the first year, 34% were performed between the first year and the fifth year, and 11% after 5 years. These data support the growing body of evidence that favors an aggressive regimen of duplex scanning surveillance of LEVGs for the life of the graft. Revised grafts have excellent patency through 10 years. (J Vasc Surg 2002;35:56-63.)