Impact of left subclavian artery management on surgical efficiency and perioperative cerebral infarction in type A aortic dissection under deep hypothermic circulatory arrest: a single-center retrospective cohort study.

BACKGROUND: Acute type A aortic dissection is a catastrophic cardiovascular emergency requiring urgent surgery. Hemiarch replacement under deep hypothermic circulatory arrest (DHCA) is a standard approach. This study compared the outcomes of two supra-aortic vessel management strategies during DHCA. METHODS: This retrospective cohort study analyzed 109 patients undergoing hemiarch replacement between May 2024 and January 2026. Patients were divided into two groups: the left subclavian artery (LSA) Occlusion Group (n = 53), in which all three arch vessels (innominate, left common carotid, and left subclavian arteries) were dissected and clamped, and the LSA Non-Occlusion Group (n = 56), in which the LSA was left untouched. Continuous and categorical variables were compared using the Mann-Whitney U test and Chi-square/Fisher's exact test, respectively. Multivariable logistic regression was performed to identify independent risk factors for perioperative cerebral infarction. RESULTS: Preoperative baseline characteristics were well-balanced between groups (all p > 0.05). The LSA Occlusion Group had significantly longer total surgical duration (320 vs. 273 min, p < 0.001), aortic cross-clamp time (126 vs. 104.5 min, p = 0.016), and DHCA time (26 vs. 22 min, p < 0.001). The incidence of perioperative cerebral infarction was significantly higher in the LSA Occlusion Group (22.64% vs. 7.14%, p = 0.044). Multivariable analysis confirmed that LSA occlusion was an independent risk factor for cerebral infarction (OR=4.36, 95% CI 1.24-15.30, p = 0.020). The 30-day mortality rate was numerically higher in the LSA Occlusion Group (20.75% vs. 10.71%) but did not reach statistical significance (p = 0.238). No significant differences were found in other major complications or recovery metrics. CONCLUSION: In this cohort, the strategy of clamping the left subclavian artery during hemiarch replacement was associated with prolonged critical intraoperative times and a significantly increased risk of perioperative cerebral infarction. LSA occlusion was identified as an independent risk factor for stroke. These findings suggest that omitting LSA manipulation may be a safer and more efficient approach, but the results require validation in larger, prospective studies.