Purpose: This report describes the results of a phase 1 trial of endovascular repair of abdominal aortic aneurysm, conducted under FDA protocol in 13 U.S. medical centers from February 1993 to December 1994.
Methods: Forty-six patients 54 to 84 years of age underwent endovascular repair of abdominal aortic aneurysm (diameter, 3.8 to 7.1 cm). Fifteen were treated with the original device (EGS-I), and 31 with a revised over-the-wire system (EGS-II). All patients were periodically observed with contrast-enhanced computed tomographic scan, color-flow duplex scan, and plain abdominal films to evaluate the stability of prosthetic location and to detect any vascular communication with or entry of blood into the aneurysm sac or change in aneurysm size.
Results: Thirty-nine implants (85%) were successful; average operating time was 194 minutes. Seven attempts were unsuccessful and were converted to open repair without complication (EGS-I, 5 of 15; EGS-II, 2 of 31). Conversions were caused by iliac stenosis in four patients, subintimal deployment in one, proximal displacement in one, and short distal neck in one. No patients died within 30 days of surgery. Complications included myocardial infarction in one patient, iliofemoral arterial injury in eight, wound infection in seven, required transfusion in eight, transient unexplained fever in nine, and minor emboli with foot petechiae in two. There were no amputations, major emboli, or episodes of mesenteric ischemia. Contrast enhancement outside the graft but within the aneurysm sac was detected initially in 17 grafts (44%), of which nine (53%) resolved spontaneously. Of eight persistent leaks into the aneurysm sac, one was controlled with transluminal balloon angioplasty and one required surgical explanation because of aneurysm enlargement. Six patients continued to have contrast enhancement, but had no evidence of aneurysm enlargement from 6 to 27 months after surgery. Hospital stay averaged 3.8 days (range, 1 to 13 days). Follow-up extends to 27 months, with one non-device related death of respiratory failure at 6 months. Metallic attachment system fracture, a device-related malfunction, was identified in nine implants (23%), which led to one removal; the remaining eight functioned normally with no untoward sequelae. The program was suspended while the defect was corrected. Preparations are complete for the phase 2 portion of the trial.
Conclusions: Endovascular repair of abdominal aortic aneurysm appears to be safe and efficacious. Long-term results and late consequences of attachment system fracture have yet to be determined. The long-term results of perigraft leak into the aneurysm sac are unknown but worrisome in view of adverse outcomes reported by other investigators.