Outcome and clinical significance of delayed endoleaks after endovascular aneurysm repair

Objective Endovascular aneurysm repair (EVAR) is considered the standard therapy for most patients with abdominal aortic aneurysm (AAA). Endoleak is a well-known EVAR-related complication that requires long-term follow-up. However, patient follow-up is often challenging outside clinical trials. We sought to evaluate the incidence and the effect of delayed endoleaks in a Veterans Administration (VA) health care system where long-term follow-up is ensured. Methods We retrospectively evaluated 213 consecutive patients who underwent EVAR at a referral Veterans Administration medical center. Age, aneurysm size, patency of lumbar and inferior mesenteric arteries, and follow-up evaluations were recorded. Type of endoleak, date of detection, and intervention were also documented. Patients who had 1 year after EVAR. All except one nontype II endoleak received prompt secondary interventions, and the one without intervention presented with aneurysm rupture. An isolated type II endoleak was detected in 34 patients at an average of 14.4 months (range, 0-76 months) after EVAR, 41% of which were detected >1 year after EVAR. Patients without a documented endoleak had a significant decrease in aneurysm size at the latest computed tomography evaluation compared to the preoperative size (4.8 vs 5.7 cm; P < .001), whereas those with isolated type II endoleak had an increase at the latest computed tomography follow-up compared to preoperative size (5.8 vs 5.7 cm). Importantly, 59% of the patients with a type II endoleak had significant AAA enlargement (0.8 cm), and delayed type II endoleak was significantly associated with sac enlargement compared to type II endoleaks detected early. No significant correlation was seen between the diameter of inferior mesenteric artery or lumbar to AAA enlargement among the patients with a type II endoleak. Secondary interventions in 12 patients with isolated type II endoleak resulted in overall aneurysm stabilization or regression. Conclusions This long-term outcome study demonstrated that delayed endoleaks