Fate of target visceral vessels in fenestrated and branched complex endovascular aortic repair

Objective: To assess branch vessel outcomes after endovascular repair of complex aortic aneurysms analysing possible factors influencing early and long-term results. Methods: The IMF&B (Italian Multicentre Fenestrated and Branched) registry enrolled 596 consecutive patients treated with fenestrated and branched endografts (F/B-EVAR) for complex aortic disease from January 2008 to December 2019 by 4 Italian academic centres. Primary endpoints of the study were technical success (defined as target visceral vessel (TVV) patency and absence of bridging device-related endoleak at final intraoperative control), and freedom from TVV instability (defined as the combined results of type 1C/3C endoleaks and patency loss) during follow-up. Secondary endpoints were overall survival and TVV-related reinterventions. Results: 591 patients (3 patients with a surgical debranching and 2 patients that died before completion were excluded from the study cohort) were treated for a total of 1991 visceral vessels targeted by either a directional branch or a fenestration. The overall technical success rate was 98.4%. Failure was related to the use of an off-the-shelf (OTS) device (CMD Vs OTS, HR: .220; p= .007) and a preoperative TVV stenosis >50% (HR: 12.460; p< .001). Mean follow-up was 25.1 months (IQ: 3-39). Overall estimated survival rates were 87%, 77.4% and 67.8% at 1, 3 and 5 years respectively (SE: .015, .022 and .032). During follow-up, TVV branch instability was observed in 91 vessels (5%): 48 type 1C/3C endoleaks (2.6%) and 43 stenoses-thromboses (2.4%). The extent of aneurysm disease (thoracoabdominal aortic aneurysm type I-III (TAAA I-III) Vs TAAA type IV (TAAA IV)/juxtarenal aortic aneurysm (JAA)/pararenal aortic aneurysm (PAA)) was the only independent predictor for developing a TVV-related type 1C/3C endoleak (HR: 3.899, 95% CI: 1.924-7.900, p< .001). Risk of patency loss was independently associated with branch configuration (HR: 8.883; p< .001, 95% CI: 3.750-21.043) and renal arteries (HR: 2.848; p= .030, 95% CI: 1.108-7.319). Estimated rates at 1, 3 and 5 years of freedom from TVV-instability and freedom from TVV-related reintervention were 96.6%, 93.8%, 90% (SE: .005, .007 and .014) and 97.4%, 95%, 91.6% (SE: .004, .007 and .013), respectively. Conclusion: Intraoperative failure to bridge a TVV was associated with a preoperative TVV stenosis >50% and the use of OTS devices. Mid-term outcomes were satisfying, with an estimated 5-year freedom from TVV instability and reintervention of 90% and 91.6%, respectively. During follow-up, the larger extent of aneurysm disease was associated with an increased risk of TVV-related endoleaks, while a branch configuration and renal arteries were more prone to patency loss.