One Year Stable Sac Predicts Worse Overall Survival and Midterm Outcomes Compared with Sac Regression after Complex Abdominal Aortic Aneurysm Repair with Fenestrated and Branched Endografts

OBJECTIVE: This multicentre, retrospective, observational study investigated the correlation between sac dynamics and outcomes in patients with complex abdominal aortic aneurysms (AAAs) after fenestrated and branched endovascular repair (FBEVAR). METHODS: Consecutive patients undergoing FBEVAR for short neck infrarenal, juxtarenal, pararenal, and paravisceral AAAs between 2015 and 2022 were included. Based on one year sac dynamics, patients with sac expansion were excluded. Comparisons were made between patients with sac regression and those with sac stability. Primary endpoints included overall survival, freedom from re-interventions, and last follow up sac regression. Secondary outcomes included freedom from aorta related death, freedom from any endoleak, and freedom from cumulative adverse events. RESULTS: The study cohort included 98 patients, 36 with sac regression and 62 with sac stability at one year. Median follow up was 34 months (interquartile range 32). The four year estimated overall survival was lower for patients with sac stability (57.2 vs. 87.5%, p = .029), which also demonstrated a lower freedom from re-interventions (89.2 vs. 94.4%, p = .11). The four year estimates of last follow up sac regression were statistically significantly higher in those with initial sac regression (46 vs. 94.7%, p < .001). Cox regression analysis identified treatment of all renal and visceral vessels (hazard ratio [HR] 2.18, p = .035) and sac regression at one year (HR 2.37, p = .015) as independent predictors of follow up sac regression. Conversely, the presence of an endoleak (HR 0.31, p = .050) predicted the absence of sac regression. One year sac regression was an independent predictor of survival (HR 3.11, p = .050). Freedom from aorta related death (96.6 vs. 100%, p = .26), endoleak (66.3 vs. 90.2%, p = .035), and cumulative adverse events (89.7 vs. 94.4%, p = .080) were in favour of patients with sac regression. CONCLUSION: Sac dynamics correlate with midterm outcomes after FBEVAR for complex AAAs. One year sac regression predicted better outcomes and survival, suggesting the need for closer surveillance in patients with stable sacs.