Abstract 11961: Impact of Left Ventricular Systolic Stress on Contractility in Hypertension Assessed by One-beat Three-dimensional Speckle Tracking Echocardiography With High Volume Rates

Abstract

Background: Left ventricular hypertrophy (LVH) is known as compensative mechanism of LV against pressure overload to reduce LV stress and maintain systolic performance. However, the relationship between LV systolic stress and strain or torsion that reflects contractility assessed by 3-dimensional speckle tracking echocardiography with high volume rates (3D-STE) has not been examined. We sought to evaluate the impact of LV systolic stress on LV contractility in hypertension (HTN). Methods: A total of 162 subjects {131 HTN patients and 31 controls (age 65±12)} were enrolled. HTN were divided into 3 groups: 47 HTN patients without LVH (age 67±12), 47 HTN patients with LVH (age 70±11) and 37 patients with hypertensive heart failure (HHF) (age 74±15). We examined LV longitudinal, circumferential and radial peak strain, LV strain rate at systole (SR) and LV torsion by 3D-STE with 70-80vps. LV systolic stress was calculated as LV end systolic radius x systolic blood pressure / thickness. Results: LV strain and SR in 3 directions and torsion decreased in HHF (longitudinal strain; control: -19±3, HTN without LVH: -18±4, HTN with LVH: -17±4, HHF: -13±4*. Torsion; 1.4±0.2, 1.4±0.3, 1.5±0.3, 1.2±0.2* °/cm, *p<0.05 vs control) associated with increased systolic stress (129±24, 141±36, 143±40, 164±51* mmHg). There was correlation between LV systolic stress and longitudinal, radial and circumferential peak strain (r=0.18, p=0.024, r=-0.22, p=0.005 and r=0.18, p=0.021, respectively) and between LV stress and LV radial SR (r=-0.1.9, p=0.018) in total subjects. There was not a significant correlation between LV systolic stress and strain or SR in 3 directions in controls. Significant correlation was found between LV stress and circumferential strain or torsion in HHF (r=0.43, r=-0.34, p<0.05), but not between LV stress and longitudinal or radial strain in HHF. Conclusion: Reduction of LV contractility assessed by LV strain, SR-S and torsion was associated with LV stress. In HHF only circumferential strain and torsion were decreased associated with increased LV stress, suggesting that the beginning of reduction in circumferential strain and torsion after deterioration of longitudinal and radial contractility due to increased systolic stress may be responsible for HHF.