Differences in global and regional left ventricular myocardial mechanics in various morphologic subtypes of patients with obstructive hypertrophic cardiomyopathy referred for ventricular septal myotomy/myectomy

Patients with obstructive hypertrophic cardiomyopathy (HC) have various left ventricular (LV) shapes: reverse septal curvature (RSC, commonly familial), sigmoid septum (SS, common in hypertensives), and concentric hypertrophy (CH). Longitudinal (systolic and early diastolic) strain rate (SR) is sensitive in detecting regional myocardial dysfunction. We sought to determine differences in longitudinal SR of patients with obstructive HC, based on LV shapes. We studied 199 consecutive patients with HC (50% men) referred for surgical myectomy. Clinical and echocardiographic parameters were recorded. LV shapes were classified on echocardiography, using basal septal 1/3 to posterior wall ratio: RSC = ratio >1.3 (extending to mid and distal septum), SS = ratio >1.3 (extending only to basal 1/3), and concentric = ratio ≤ 1.3. Longitudinal systolic and early diastolic SRs were measured from apical 4- and 2-chamber views (VVI 2.0; Siemens, Erlangen). Distribution of RSC, SS, and CH was 50%, 28%, and 22%, respectively. Patients with RSC were significantly younger (47 ± 12 vs 64 ± 10 and 57 ± 11, respectively) with lower hypertension (40% vs71% and 67%, respectively) than patients with SS or CH (both p