Immediate and late explantation of endovascular aortic grafts: the endovascular technologies experience

The morbidity and clinical outcome of the failure to successfully repair an abdominal aortic aneurysm with Endovascular Technologies (EVT) grafts, resulting in explantation of the device, was assessed.

The records of all patients worldwide undergoing attempted endovascular repair with EVT devices from February 1993 to October 1997 were retrospectively reviewed. Of 669 patients, 19 (3%) were converted to open procedure with immediate explantation during the initial attempt at endovascular repair, and 27 patients (4%) required explantation at a later date, ranging from 1 day to 40 months. The incidence, morbidity, mortality, and effect on clinical outcome were evaluated.

Causes of immediate conversion with explantation were: inaccurate deployment of the proximal or distal attachment systems (11 of 19; 58%); twists in the system (3 of 19; 16%); mechanism malfunction during deployment (4 of 19; 21%); and an aortic tear (1 of 19; 5%). Among the 27 patients undergoing late explantation, 20 (74%) did so because of persistent endoleaks. Three cases (11%) were performed because of aneurysm rupture, three (11%) because of graft occlusion, one because of aortic dissection (4%), and one (4%) because of graft migration into the aneurysm sac. The overall perioperative mortality rate was 11% (2 of 19) for immediate explantation and 7% (2 of 27) for late explantation. The average length-of-stay was 11 days for immediate explantation and 14 days for late explantation (NS). Complications included myocardial infarction (4%), pulmonary insufficiency (13%), wound infection (4%), and permanent renal failure (2%). There were no significant differences in the incidence rates of these complications between immediate and late explants. No cases of limb loss occurred. Median American Society of Anesthetists (ASA) classification was 3, and there was no correlation between ASA classification and mortality rate. Average operating time was 374 minutes for immediate explantation (including the time for the failed endovascular procedure) and 185 minutes for late explantation.

Immediate and late explantation are infrequent events, occurring in 3% and 4%, respectively, of attempted EVT endovascular aortic stent placements. The mortality rate was higher for both immediate (11%; P <.05) and late (7%; NS) explantation when compared with the mortality rate of all patients undergoing EVT aortic endograft placement (1.5%). There does not appear to be increased long-term morbidity among patients undergoing successful explantation. Early recognition of the need to convert to open procedure, device improvement, and increased operator experience should continue to minimize the incidence of immediate and late explantation and their associated complications.