Significant sac retraction after endovascular aneurysm repair is a robust indicator of durable treatment success

ObjectivesThe principal aim of this study was to demonstrate that significant sac retraction (SSR) was a predictive marker of durable success after endovascular aortic repair (EVAR). If verified, follow-up (FU) of patients with SSR may become unnecessary. In addition, the clinical features of the patients and aneurysms were analyzed to identify predictive factors of SSR.MethodsA group of 371 patients treated by EVAR had a complete clinical exam, computed tomography (CT) scan, and duplex scan follow-up. Data were collected prospectively and analyzed retrospectively. We assessed the difference between the largest diameter of the aneurysm (D) and the diameter of the stent-graft body (D1) on each postoperative CT scan. SSR was defined as a minimum of 75% reduction of this difference between the first and any of the following CT scans. Treatment success was defined as survival free of aneurysm-related death, type I or III endoleak, aneurysm expansion exceeding 5 mm, rupture, surgical conversion, migration, and graft occlusion. To assess the predictive factors of SSR, we performed a multivariable analysis and a logistic regression of the most significant variables.ResultsSSR was observed in 24.8% (92/371) of the patients after an average of 26 ± 21 months of FU. The mean duration of FU in this group was 50 ± 26 months (vs 45 ± 25 months; P = NS). Survival was significantly longer in the SSR group (96 ± 3 months vs 93 ± 3 months; P < .05). No rupture, surgical, or endovascular conversion was reported in the SSR group. The frequency of type I (2.2% vs 15.4%; P < .001), type II (3.3% vs 29.4%; P < 10-6), and secondary interventions (3.3% vs 13.3%;P < .05) was lower in the SSR group. All type I and III endoleaks were diagnosed and treated before SSR detection. Since SSR was detected, treatment success remained until last follow-up in 98.9% (91 of 92) of the patients. The independent predictive factors of SSR were abdominal aortic aneurysm (AAA) diameter <55 mm (odds ratio [OR] 3.91; 95% confidence interval [CI]: 2.16-7.11), infra renal aorta diameter <23 mm (OR 2.96; 95% CI: 1.74-5.03), and a proximal neck length >22 mm (OR 2.41; 95% CI: 1.42-4.10).ConclusionIn this series, SSR was accurately predictive of a durable success after EVAR. It occurred mostly in patients with a favorable anatomy. Less intensive follow-up work up seems to be safe in patients with SSR.