ABSTRACT: Background This study compared left ventricular (LV) characteristics between patients with type-A and type-B aortic dissection (AD) and evaluated the ability of LV remodeling phenotypes (hypertrophy, concentricity, or geometric patterns) to predict mortality in both AD types. Methods and Results We evaluated 236 patients with type A and 120 patients with type B who had echocardiograms within 60 days before or after AD diagnosis (median [25th, 75th percentiles] time difference between echocardiogram and AD diagnosis=1 [0, 6] days) from 3 centers. Patients were stratified according to LV phenotypes, and early (90-day) and late (1-year) mortality after AD diagnosis were assessed. In adjusted logistic regression analysis, patients with type A had higher and lower odds of concentric and eccentric hypertrophy (odds ratio [OR], 2.56; 95% CI, 1.50-4.36; P<0.001; and OR, 0.55; 95% CI, 0.31-0.97; P=0.039, respectively) than those with type B. Results of multivariable Cox-regression analysis showed that LV remodeling phenotypes were not related to mortality in patients with type B. By contrast, LV concentricity was associated with greater early and late mortality (hazard ratio [HR], 2.22; 95% CI, 1.24-3.96; P=0.007 and HR, 2.06; 95% CI, 1.20-3.54; P=0.009, respectively) in type A. In further analysis considering normal LV geometry as reference, LV concentric remodeling and concentric hypertrophy were associated with early mortality (HR, 7.78; 95% CI, 2.35-25.78; P<0.001 and HR, 4.38; 95% CI, 1.47-13.11; P=0.008, respectively), whereas concentric remodeling was associated with late mortality (HR, 5.40; 95% CI, 1.91-15.26; P<0.001) among patients with type A. Assessment of LV geometric patterns and concentricity provided incremental prognostic value in predicting early and late mortality beyond clinical variables in patients with type A based on net reclassification improvement and integrated discrimination improvement. Conclusions LV geometric patterns derived from LV concentricity were associated with greater mortality among patients with type A and may be markers of adverse prognosis in this population.