Time-of-day discrepancy for the long-term surgical outcome of patients with aortic dissection

OBJECTIVES: It has been suggested that the time of day when cardiovascular surgery is performed may affect the surgery outcomes. This study investigated whether there was a difference in risk-adjusted mortality and morbidity outcomes between patients undergoing acute aortic dissection (AAD) during the day or the night. METHODS: Consecutive patients who had undergone Stanford A AAD surgery were enrolled between 2016 and 2020. In the daytime group, surgery was performed between 08:00 and 20:00, and in the nighttime group between 20:00 and 8:00. The primary outcome was in-hospital overall mortality, and the secondary outcomes were overall mortality within a median follow-up time of 35.2 (17.0, 53.5) months and the occurrence of re-entry tears and major bleeding. RESULTS: A total of 925 patients were enrolled. The primary outcome of in-hospital overall mortality did not differ significantly between patients who received daytime or nighttime surgery. Similarly, the secondary outcomes of overall mortality during the follow-up and incidence of re-entry tears and major bleeding did not differ significantly between the groups. Subgroup analysis was also performed according to the surgery type (modified triple-branched stent graft implantation or frozen elephant trunk implantation) and surgical approach (partial upper sternotomy or full median sternotomy) confirming that the time of surgery did not significantly influence the outcomes. Cox regression analysis showed that time from onset to admission (P = 0.036) and time from the onset to surgery (P = 0.045) were significant risk factors for increased mortality during follow-up. CONCLUSIONS: The time of day when thoracotomy was performed did not significantly affect the clinical outcome and is therefore not a consideration for the improvement of outcome in Stanford A AAD patients.