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Type A aortic dissection in the East and West: A comparative study between two hospitals from China and the US.

BACKGROUND
In this study, we compare the clinical characteristics, intraoperative management, and postoperative outcomes of patients with acute type A aortic dissection (ATAAD) between two academic medical hospitals in the United States and China.


METHODS
From January 2011 to December 2017, 641 and 150 patients from Nanjing Drum Tower Hospital (NDTH) and Massachusetts General Hospital (MGH) were enrolled. Patient demographics, clinical features, surgical techniques, and postoperative outcomes were compared.


RESULTS
The annual number of patients presenting with ATAAD at MGH remained relatively stable, while the number at NDTH increased significantly over the study period. The average age was 51 years at NDTH and 61 years at MGH (P < .001). The percentage of patients with known hypertension at the two centers was similar. The time interval from onset of symptoms to diagnosis was significantly longer at NDTH than MGH (11 vs 3.5 hours; P < .001). Associated complications at presentation were more common at NDTH than MGH. More than 90% of patients (91% NDTH and 92% MGH) underwent surgery. The postoperative stroke rate was higher at MGH (12% vs 4%; P < .001); however, the 30-day mortality rate was lower (7% vs 16%; P = .006).


CONCLUSIONS
There was a significant increase in the number of ATAAD at NDTH during the study period while the number at MGH remained stable. Hypertension was a common major risk factor; however, the onset of ATAAD at NDTH was nearly one decade earlier than MGH. Chinese patients tended to have more complicated preoperative pathophysiology at presentation and underwent more extensive surgical repair.