Sarcopenia as a predictor of long-term mortality after acute type a aortic dissection surgery: a retrospective observational study

Acute type A aortic dissection (AAAD) is a life-threatening condition requiring immediate surgical intervention, and despite advances in perioperative care, postoperative mortality remains a major concern.Sarcopenia, characterized by reduced muscle mass and function, has emerged as a prognostic factor in various surgical populations.This retrospective single-center study assessed the prognostic impact of sarcopenia on postoperative outcomes in patients who underwent surgery for AAAD at Chonnam National University Hospital between January 2021 and December 2023.Sarcopenia was defined using total psoas area derived from preoperative computed tomography scans, with automated segmentation performed using the pre-trained Segment Anything Model 2 (SAM2) optimized for psoas detection.A total of 83 patients were included, of whom 31 (37.3%) were classified as having sarcopenia.The primary outcome was all-cause mortality, further classified into early mortality (within 30 days, including in-hospital deaths occurring after 30 days) and late mortality (beyond 30 days postoperatively).While early mortality did not differ significantly between the sarcopenia and non-sarcopenia groups, late mortality was significantly higher in the sarcopenia group (22.6% vs. 5.8%, p=0.023).Multivariable Cox regression analysis identified age (hazard ratio: 1.072, p=0.001) and sarcopenia (hazard ratio: 0.289, p=0.005) as independent predictors of late mortality.These findings suggest that while sarcopenia does not affect early mortality following AAAD surgery, it is significantly associated with increased late mortality, underscoring the need for early detection and management strategies to improve long-term outcomes in this high-risk population.