Abstract 12809: The Mechanism of Preserved Left Ventricular Ejection Fraction in Patients with Hypertension: A 3D Speckle Tracking Imaging Study
Background: Systemic hypertension may lead to left ventricular (LV) remodeling and in turn to diastolic dysfunction in the presence of preserved systolic function. The goal of this study was to investigate the mechanism of preserved ejection fraction (EF) by 3D speckle tracking echocardiography (3D STE) in patients with hypertension.
Methods: Simultaneous 2D and 3D (frame rate of 35 ± 10 Hz by ECG gating over 4 cardiac cycles) imaging data were acquired using the GE Vivid E9 system in 104 hypertensive patients (60 men, mean age 51±13years, blood pressure 169±25/100±17 mmHg) and 104 age- and gender-matched normotensive subjects (age 51±12 years, blood pressure 118±6/74±6 mmHg). The relative wall thickness (RWT) was calculated as the sum of ant-septal and posterior wall thickness divided by the LV end diastolic dimension. Analysis of 3D strain was performed with automated software allowing manual adjustment for myocardial borders detection. The LV mass index, EF and the values of 3D global LV longitudinal,circumferential and area strains were obtained from 3D analysis.
Results: LV mass index and RWT were significantly higher in the hypertensive patients than normotensive controls, indicating concentric LV remodeling in hypertension. The longitudinal and area strains were significantly lower in hypertension than normotension, whereas the circumferential strain did not differ between the two groups. LVEF was significantly higher in hypertension, which could be attributable to the increase in LV twist (Table).
Conclusions: In compensated LV remodeling in hypertension, LV wall thickening increases with preserved EF and increased twist. This may contribute to supra-normal LVEF in hypertension despite depressed longitudinal and area strains; the circumferential strain remains preserved which leads to a higher LV twist as a compensatory mechanism.
- © 2013 by American Heart Association, Inc.