Intraoperative endoleak during EVAR: frequency, nature, and significance.

OBJECTIVE: Endoleaks are critical complications of endovascular abdominal aortic aneurysm repair (EVAR). This study sought to determine the frequency and nature of intraoperative endoleaks and their impact on postoperative endoleak-related events. METHODS: A retrospective chart review was performed of all patients who underwent EVAR at our institution. The impact of intraoperative endoleaks on postoperative endoleak rates and endoleak-related reintervention rates were assessed. RESULTS: From December 18, 1996, to May 21, 2003, 241 patients underwent EVAR. An endoleak was observed during 126 (52.3%) procedures. Type I endoleaks were observed in 63 (26.1%) cases: 35 proximal and 31 distal endoleaks (3 cases at both attachments). Angioplasty, additional cuff placement, or stenting corrected 59 (89.4%) of these endoleaks. A total of 71 type II intraoperative endoleaks (29.5%) and 8 type IV endoleaks (3.3%) were observed without any attempted corrective maneuvers. Ten type III endoleaks (4.2%) occurred but all resolved with angioplasty or additional cuff placement. In all, 86 (35.7%) endoleaks persisted on completion angiogram. Patients with a type I or type II intraoperative endoleak were more likely to have an endoleak at 1.5 years (31.4% vs. 21.6%, P=.018). Reinterventions were required more often after an intraoperative type I endoleak (10% vs. 4%, P=.003). Patients with intraoperative endoleaks demonstrated a trend toward less postoperative aneurysm diameter reduction at 2 years (43.8% vs. 74.5%, P=.104). CONCLUSION: The presence of a type I or a type II endoleak during EVAR significantly increases the likelihood of a postoperative endoleak and should prompt a high degree of suspicion during follow-up.