Two Year Outcomes following Off the Shelf Inner Branch Endograft Implantation for the Treatment of Complex Abdominal and Thoraco-abdominal Aortic Aneurysm: Analysis from the Multicentre ItaliaN Branched Registry of E-nside EnDograft (INBREED)

Objective: This study aimed to report the 2 year outcomes obtained with the E-nside endograft (Artivion) for the treatment of complex abdominal aortic aneurysm (cAAA) and thoraco-abdominal aortic aneurysm (TAAA). Methods: This was a prospective, multicentre study. Data from the multicentre ItaliaN Branched Registry of E-nside EnDograft (INBREED) were analysed. Primary endpoints were aortic related death, main endograft instability, and target vessel (TV) instability. Secondary endpoints were any re-intervention, TV related patency and endoleaks, and aneurysm sac dynamics at 1 year. Results: There were 206 patients (111 TAAAs, 53.9%; 95 cAAAs, 46.1%), accounting for 795 TVs successfully incorporated through an inner branch; 28.6% had an urgent repair. At 2 years, overall survival was 90.3% (95% confidence interval [CI] 87 - 97%); freedom from aortic related death was 96% (95% CI 94 - 100%), and freedom from endograft instability related to proximal seal failure was 97.6% (95% CI 95 - 100%). Freedom from TV instability was 95.9% (95% CI 93 - 97%) and freedom from re-intervention was 98% (95% CI 96 - 99%). For renal arteries, primary patency was 96.1% (95% CI 93 - 98%) and freedom from endoleak was 99.4% (95% CI 98 - 100%). At 1 year, 26% of cases had sac regression and 68% remained stable. Conclusion: The E-nside endograft demonstrated good 2 year outcomes in the treatment of cAAA and TAAA. It safely and effectively prevented aneurysm related death and guaranteed low TV instability. During planning, attention should be given to the proximal sealing zone to prevent graft instability during follow up.