Abstract 12513: Comparison of Global Myocardial Function With 2 Types of Pressure-Overload Left Ventricular Hypertrophy Using Two-Dimentional Speckle-Tracking Echocardiography

Abstract

Introduction: Left ventricular hypertrophy (LVH) secondary to hypertension and aortic stenosis (AS) are often considered together to be pressure overload hypertrophy. Comparisons of myocardial function by the 2 most common causes of LVH are limited. The global LV afterload that may be assessed by valvuloarterial impedance plays a detrimental effect on LV systolic function. Hypothesis: We hypothesized that important differences may exist in the myocardial function with these 2 origins of pressure-overload LVH. Methods: Global LV longitudinal strain (GLS) were measured using speckle-tracking echocardiography in 38 hypertensive LVH (H-LVH) patients and 36 patients with severe AS and preserved LV ejection fraction. To estimate the global LV afterload, we calculated the valvuloarterial impedance (Z va ) as the sum of the systolic arterial pressure and the mean transvalvular pressure gradient divided by the stroke volume index. Results: The patients were divided into two groups according to the level of Z va : low Z va (Z va <3mmHg ml/m 2 , n=25) and high Z va (Z va ≥3mmHg ml/m 2 , n=49). GLS was reduced in the high Z va group (p<0.05). The patients in the high Z va group were divided into two subgroups: AS group (n=28) and H-LVH group (n=21). Systolic blood pressure was higher in the H-LVH group than in the AS group (p<0.0001). However, LV mass index and LV ejection fraction were not significantly differences. GLS was significantly reduced in the AS group (p<0.0001). In the AS group, GLS was significantly correlated with Zva (r=0.44). However, there was no correlation between GLS and mean transaortic pressure gradient. Conclusions: Despite of similar global LV afterload and LV hypertrophy, myocardial LV longitudinal systolic function is impaired in patients with severe AS compared with H-LVH patients. However, there is no correlation between AS severity and LV longitudinal deformation. The magnitude of the global LV afterload as reflected by Z va is a powerful determinant of altered LV longitudinal deformation in severe AS patinets with preserved LV ejection fraction.