Left Atrial Volume Index: A Predictor of Adverse Outcome in Patients With Hypertrophic Cardiomyopathy

Background: Despite the relatively benign course for the majority of patients with hypertrophic cardiomyopathy (HCM), this disease may cause sudden cardiac death and progressive heart failure (HF). The aim of this study was to investigate useful parameters for predicting adverse outcomes of HCM, including echocardiographic parameters, cardiac magnetic resonance (CMR), and clinical markers. Methods: Eighty-one patients with nonapical HCM (51 men; mean age, 57 +/- 14 years) who underwent CMR and echocardiography were prospectively evaluated. Cardiovascular events were defined as hospitalization for worsening HF, stroke, or cardiovascular death. Results: During the mean follow-up period of 41 +/- 17 months, there were 17 cardiovascular events (5 deaths, 7 hospitalizations for worsening HF, and 5 strokes). Univariate analysis showed that older age, atrial fibrillation, elevated E/E' ratio, increased left atrial (LA) volume index, presence of mitral regurgitation grade >2, New York Heart Association class III or IV, and late gadolinium enhancement >= 6% were associated with cardiovascular events. In multivariate Cox regression analysis, increased LA volume index was found to be an independent predictor of cardiovascular events (for each 5 mL/m(2) increase, hazard ratio, 1.28; 95% confidence interval, 1.10-1.48; P < .01). Increased LA volume index was also revealed to be an independent predictor for cardiovascular events other than death (for each 5 mL/m(2) increase, hazard ratio, 1.44; 95% confidence interval, 1.12-1.83; P < .01). Conclusion: LA volume index is independently associated with adverse outcomes in patients with HCM and provides additional prognostic information. (J Am Soc Echocardiogr 2009;22:1338-43.)