Proximal adventitial inversion with distal single-branch stent grafting versus Sun’s procedure in acute type A aortic dissection: a comparative study

BACKGROUND: We innovatively modified Sun's procedure by substituting the distal frozen elephant trunk (FET) stent with an intraoperative single-branch stent and employing the adventitial inversion technique at the proximal anastomosis. This study aims to evaluate the perioperative efficacy and short-term outcomes associated with this modified procedure. METHOD: From January 2019 to December 2024, 147 consecutive patients with acute type A aortic dissection underwent surgery. Of these, 73 patients had ascending aorta and total arch replacement with distal stent grafting. Patients were divided into two groups based on surgical technique: Group A (n = 41) received proximal adventitial inversion technique with distal single-branch stent implantation, while Group B (n = 32) underwent Sun's procedure. Comparative analysis of preoperative characteristics, intraoperative parameters, and postoperative outcomes was performed. RESULTS: The groups demonstrated comparable preoperative characteristics. Intraoperatively, the modified technique achieved 39.8% shorter total operation time (median 320 vs. 532.5 min; P < 0.001) with 38.1% reduction in cardiopulmonary bypass (CPB) time (151.3 ± 2.6 vs. 244.3 ± 6.9 min; P < 0.001). This technical modification translated to 65% lower blood product requirements (median red blood cells units: 2 vs. 6; total transfusion volume: 920 vs. 2640 mL; P < 0.001). Postoperatively, Group A exhibited 87.9% shorter mechanical ventilation duration (13.5 vs. 111.5 h; P < 0.001) and 64.7% reduced ICU stay duration (3 vs. 8.5 days; P < 0.001), alongside 63.5% lower composite complication rate (17.1% vs. 46.9%; P = 0.006). Notably, A trend towards reduction in postoperative cardiogenic shock (0% vs. 12.5%; P = 0.070) and surgical re-exploration for bleeding (0% vs. 3.1%; P = 0.438) was observed in Group A. Critically, both techniques demonstrated equivalent in-hospital mortality (4.9% vs. 6.3%; P = 1.000). CONCLUSION: Our modified technique demonstrates comparable safety to Sun's procedure while offering superior operative efficiency and reduced postoperative morbidity in Acute type A aortic dissection (ATAAD) repair. These findings support broader clinical application of this innovative approach.