Abstract 11093: Layer-specific Quantification of Myocardial Deformation by Strain Echocardiography May Reveal the Mechanism of Preserved Left Ventricular Ejection Fraction in Patients With Hypertrophic Cardiomyopathy

Purpose: We aimed to evaluate compensatory mechanisms in hypertrophic cardiomyopathy (HCM) patients (pts) with preserved left-ventricular (LV) ejection fraction (EF). Methods: Speckle-tracking echocardiography (Vivid E9, GE) was performed in 50 HCM with preserved LV EF (38 m; 49± 14 y, all LV EF > 55%) and 50 age, gender matched controls (38 m; 49±12 y). The global and segmental longitudinal (LS), circumferential (CS) and radial strain (RS) strains of endocardia (End), mid-wall and epicardia layers were analyzed using a novel layer-specific TTE. The ratio of End to epicardia strain (End/Epi) was calculated. Results: The LV EF were similar in pts and controls (64±8 vs 64±7 %, p=0.95). The diastolic function was significantly impaired in HCM pts compared with controls (E/E’:18.4±8.4 vs 8.6 ±2.4, p<0.0001). The absolute value of LS and CS was reserved at apical End layers (-34±7 vs -35±6, p=0.44); the remaining segments and LV global LS and CS of three layers were significantly smaller (LS,-16±5 vs -22±3; CS...