Late conversion of aortic stent grafts

Abstract

Objectives: The frequency of late removal of endovascular abdominal aortic repair (EVAR) parallels the rise of endovascular aortic repair. Evaluation of outcomes for EVAR explants may identify risks for complications and alter clinical management.

Methods: A patient database was used to identify EVAR patients requiring explant >1 month after implant. A retrospective analysis was conducted of the type of graft, duration of implant, reason for removal, operative technique, death, and length of stay.

Results: During 1999 through 2007, 1606 EVARs were performed, and 25 patients required explantation, with an additional 16 referred from other institutions (N = 41). The average age was 73 years (range, 50-87 years); 90% were men. Grafts were excised after a median of 33.3 months (range, 3-93 months). Explanted grafts included 16 AneuRx (40%), 7 Ancure (17%), 6 Excluder (15%), 4 Zenith (10%), 4 Talent (10%), 1 Cook Aortomonoiliac rupture graft, 1 Endologix, 1 Quantum LP, and 1 homemade tube graft. Overall hospital mortality was 19% and occurred after conversion for rupture in 4, and in infected graft, aortoenteric fistula, repair of new aneurysm of the visceral segment, and claudication due to graft stenosis in one patient each. Elective EVAR-related mortality was 3.3%. Mortality was higher in patients with rupture compared with nonrupture (4 of 6 vs 3 of 35, P <or= .01). Thirty patients (73%) had one or more endoleaks (type I, 16; II, 9; III, 9; endotension, 5). Migration (n = 10), rupture (n = 6), aortoenteric fistula (n = 3), infection (n = 1), limb thrombosis (n = 3), and claudication (n =1) were also factors. Proximal aortic control was above the endograft (supravisceral, 23; suprarenal, 12; infrarenal, 6). Reconstruction was an aortoiliac repair in 63% and tube graft in 25%. Grafts with suprarenal fixation required longer proximal aortic clamp time of 43 minutes vs 28 minutes for infrarenal fixation. Complete graft removal was achieved in 85%. Proximal or distal portions of the endograft were incorporated into the repair in the remaining six.

Conclusion: Elective EVAR conversion, although technically challenging may be done with mortality similar to primary open repair. Mortality for conversion for infected grafts and ruptured aneurysms remains high. EVAR is associated with continued risk of conversion, and surveillance may identify late complications that require removal, justifying lifelong monitoring. Aggressive management of late complications and elective conversion may minimize the mortality associated with this procedure.