Epidemiology and Surgical Outcomes of Stanford Type A Acute Aortic Dissection in a Northern Japanese Urban Hospital

Background: Stanford type A acute aortic dissection (TAAD) presents a critical scenario necessitating emergent surgery by cardiovascular surgeons. Over time, outcomes of emergent TAAD operations have significantly improved, with several reports showing seasonal difference in TAAD outcomes. The objective of this study was to analyse the seasonal difference in the characteristics of TAAD, especially in the winter season, and the surgical result of TAAD in a northern Japanese urban hospital. Methods: We reviewed 75 patients who received emergent operation for TAAD from 2017 to 2023 in Sapporo Kojinkai Memorial Hospital, Hokkaido, Japan. For all patients, we analysed the seasonal difference, especially in winter, presenting complaints, patient characteristics and surgical results. Results: Among all included patients, 29 (38.7%) complained of chest pain. The mean age of patients was 69.7 ± 13.1 years, with 49.3% men. Ascending aortic replacement was performed in 49.3% of patients. The rate of onset was not significantly different between seasons. Comparing winter and other seasons, the patients who had TAAD in winter were significantly older, with a greater proportion of women. Conclusion: This study underscores the unique epidemiological profile of TAAD in Sapporo, Japan, characterised by distinct seasonal variations in patient demographics. While older patients exhibited a higher propensity for TAAD during winter months, surgical outcomes remained favourable, aligning with international trends. However, larger-scale and multicentre analyses are warranted to further elucidate the impact of seasonal variations on TAAD occurrence and outcomes in Sapporo and beyond.