Outcomes of Asian and Caucasian patients with type A aortic intramural haematoma: a multicentre registry analysis.

BACKGROUND: Outcomes of aortic intramural haematoma (IMH) have shown disparities between Asian and Caucasian patients. We evaluated the heterogeneity of treatment effects in Asian and Caucasian patients with type A IMH. METHODS: This multicentre registry included individual patient data from 485 patients with type A IMH, collected from eight institutions (five Asian and three Western). Overall mortality was the primary outcome. RESULTS: Compared with their Asian counterparts, Caucasian patients (n=147) were older (69.3 vs 66.8 years) and had a higher prevalence of bicuspid aortic valve (4.1% vs 0.6%), visceral ischaemia (6.1% vs 1.5%), limb ischaemia (3.4% vs 0.3%) and shock (21.1% vs 6.8%), thicker haematoma (12.5±4.8 vs 10.5±5.2 mm) and larger ascending aortas (51.5±7.8 vs 47.7±7.2 mm). Urgent surgery was performed in 129 patients (26.6%), while 356 patients (73.4%) received medical treatment. Initial medical treatment was more common in Asian patients (85.5% vs 45.6%). During follow-up (median, 6.9 years), 121 deaths occurred. After adjustment for potential confounding factors, there was no significant difference regarding long-term mortality between Asian and Caucasian (HR, 1.38; 95% CI 0.73 to 2.60; p=0.32). Age (HR 1.42; 95% CI 1.17 to 1.72; p<0.001), ascending aorta diameter (HR 1.05; 95% CI 1.02 to 1.09; p<0.001) and medical treatment due to prohibitive surgical risk (HR 3.00; 95% CI 1.45 to 6.22; p<0.003) were independent predictors for long-term mortality. CONCLUSIONS: In patients with type A IMH, race was not associated with long-term mortality. The initial clinical presentation and imaging characteristics were the primary determinants of clinical outcomes.