Impact of elephant trunk on distal remodelling after surgery for acute type I aortic dissection

OBJECTIVES For surgical repair of acute type I aortic dissection, total arch replacement (TAR) with frozen elephant trunk (FET) has been known to result in better long-term remodelling of residual false lumen. This study aimed to investigate the impact of elephant trunks by comparing long-term remodelling features among different extents and strategies of aortic replacement. METHODS We conducted a single-centre retrospective analysis of patients who underwent surgical repair for acute type I aortic dissection from January 2004 to June 2022. Patients were categorized based on the surgical strategy employed: non-TAR, conventional TAR, TAR with classic elephant trunk (CET), and TAR-FET. The primary outcomes were positive remodelling of the residual false lumen and composite aortic events, with secondary outcomes focusing on early postoperative results. RESULTS A total of 327 patients were included. TAR, when combined with insertion of an elephant trunk, whether it was stented or not, significantly promoted favourable aortic remodelling (P < 0.001). Compared with TAR-CET, the FET group tended towards faster false lumen thrombosis and regression, albeit without a significant difference in ultimate remodelling rates; 1-year and 5-year rates of proximal descending false lumen thrombosis were 85.4% (95% confidence interval [CI], 69.2–100) and 90.3% (95% CI, 75.9–100), respectively, after TAR-FET; additionally, these aforementioned rates were 65.7% (95% CI, 54.7–76.6) and 81.9% (95% CI, 71.8–91.9), respectively, after TAR-CET. No significant differences were observed in early postoperative outcomes or overall survival. CONCLUSIONS The favourable remodelling of the residual false lumen after TAR-FET shown in this study is in line with previous studies. CET might be a reasonable alternative to FET according to the individual patient risk profiles and institutional logistics situation.