False aneurysms after prosthetic reconstructions for aortoiliac obstructive disease.

Several aspects of false aneurysm development after prosthetic resconstruction for aortoiliac obstructive disease were studied. For this purpose the long-term results (up to 20 years of follow-up) of 518 patients with implanted arterial prostheses in the aortoiliofemoral tract were retrospectively evaluated. Completeness of follow-up data was 83.2% 15 years after operation. A total of 101 false aneurysms (21 aortic, 53 iliac, and 27 femoral) were detected in 69 patients and verified by operation. The incidence per patient was 69 of 518 patients (13.3%). The incidences per anastomosis were: aortic, 21 of 438 anastomoses (4.8%); iliac, 53 of 835 anastomoses (6.3%); and femoral, 27 of 198 anastomoses (13.6%). Almost one half (47.5%) of all the false aneurysms were asymptomatic and were detected by angiography or ultrasonography. Chances for late survivors to develop a false aneurysm during follow-up were calculated by the life-table method. The chance to be free of a false aneurysm at any site was 77.2% 15 years after operation. These chances were 92.3%, 84.5%, and 76.2% for aortic, iliac, and femoral anastomoses, respectively. Analyses of subgroups showed that the development of a false aneurysm was significantly correlated with the presence of hypertension, multilevel disease, the type of suture material, and the type of anastomosis. These results indicate unexpectedly high chances for the development of false aneurysms in long-term survivors after aortoiliac or aortofemoral prosthetic reconstructions. We advocate the use of a life-long follow-up schedule with periodic angiography and ultrasonography for these patients.