Echocardiographic predictors of severe heart failure symptoms in hypertrophic cardiomyopathy patients with sinus rhythm

BACKGROUND: Symptoms in hypertrophic cardiomyopathy (HC) appear to be caused by diastolic dysfunction, myocardial ischemia, left ventricle (LV) outflow obstruction, and atrial fibrillation. However, clinical deterioration and severe heart failure symptoms can be observed in patients without any of these factors. Thus, the aim of this study is to determine the echocardiographic predictors of severe heart failure symptoms in patients with HC. METHODS AND RESULTS: 86 HC patients were compared according to symptomatic status. Patients with severe heart failure symptoms were older, preponderantly female, had more often LV outflow obstruction and mitral regurgitation, longer E wave deceleration time (EDt), higher E/Ea ratios and lower LV tissue Doppler (TD) velocities when compared to rest of the patients. LV outflow obstruction (r = 0.43, R(2 )= 0.19, p < 0.0001), LV lateral mitral annular systolic TD velocity (LMSa) (r = 0.51, R(2 )= 0.26, p < 0.006) and EDt (r = 0.55, R(2 )= 0.30, p < 0.027) were found to be the independent predictors for severe heart failure symptoms in forward stepwise regression. CONCLUSION: In HCM patients with sinus rhythm and normal LV systolic function, LMSa, EDt and LV outflow obstruction are independent predictors of heart failure symptoms. Diastolic dysfunction determined with EDt, occult systolic dysfunction which is detected with TD analysis, and afterload increase as result of LV outflow obstruction seem to be the main echocardiographic factors affecting symptomatic status in HCM patients with sinus rhythm and normal systolic function.