Abstract 13262: Impact of Right Ventricular Longitudinal Strain at Rest and Under Dobutamine Stress on Outcome in Low-Flow, Low-Gradient Aortic stenosis -Results from the TOPAS Study
Background: We previously reported that left ventricular global longitudinal strain (LVLS) is a powerful predictor of outcome in patients with low-flow, low-gradient (LF-LG) aortic stenosis (AS) and low LV ejection fraction (LVEF). The aim of this study was to examine the impact of RV longitudinal strain (RVLS) on all-cause mortality in this population.
Methods: 215 patients (73±10 yr; 77% men) with LF-LG AS (mean gradient<40 mmHg and indexed aortic valve area [AVA]≤0.6 cm2/m2) and low EF (≤40%) were prospectively recruited. Free wall RVLS was retrospectively measured at rest and under dobutamine stress by 2D speckle-tracking. Resting RVLS measurement was available in 128(60%) patients and stress RVLS in 58(45%) of the remaining 128 patients.
Results: Among these 128 patients, 80(63%) underwent aortic valve replacement (AVR) within 3 months following inclusion, and 59(46%)died during a mean follow up of 2.4±2.1 yrs. Average RVLS was 17.5±5.5% at rest and 18.1±6.0 at stress. Patients with reduced resting RVLS had increased risk of all-cause mortality (p=0.04). In multivariable Cox analysis adjusted for age, gender, previous myocardial infarction, AS severity, LVLS, and type of treatment (AVR vs. No AVR), resting RVLS (HR=1.53 per 5% decrease; 95% CI: 1.09 to 2.19; p=0.01) remained an independent predictor of all-cause mortality. In the subgroup of patients with stress RVLS available, 28(48%) died. In this subgroup, stress RVLS was associated with higher risk of mortality (HR=1.54 per 5% decrease; 95% CI 1.08 to 2.28; p=0.01). In multivariable Cox analysis adjusted for age, AS severity, LVEF and type of treatment, stress RVLS remained an independent predictor of all-causes mortality (HR=1.86 per 5% decrease; 95% CI 1.22 to 3.02 ; p=0.003). After further adjustment for resting RVLS value, stress RVLS remained a powerful independent predictor of mortality (HR=1.84 per 5% decrease; 95% CI 1.15 to 3.23; p=0.008).
Conclusion: In this series of patients with LF-LG and low EF AS, RVLS was an independent predictor of mortality. Furthermore, stress RVLS provided incremental prognostic value beyond that obtained from resting RVLS. Thus, RVLS measurement at rest and under dobutamine stress may be helpful to enhance risk stratification in this high risk population.
- © 2013 by American Heart Association, Inc.