Incremental prognostic value of left ventricular global longitudinal strain in patients with aortic stenosis and preserved ejection fraction.

BACKGROUND: We sought to assess the utility of left ventricular global longitudinal strain (LV-GLS) in predicting mortality in moderate to severe and paradoxical severe aortic stenosis (AS) patients with preserved ejection fraction.

METHODS AND RESULTS: We studied 395 AS patients (70 ± 14 years, 57% men) with aortic valve area <1.3 cm(2) evaluated between January to June 2008 (excluding severe other valve disease and LV ejection fraction <50%). Clinical and echocardiographic data were recorded. LV-GLS was analyzed using Velocity Vector Imaging. AS patients were classified as (a) moderate-severe (n=93; aortic valve area, 1.1-1.3 cm(2)), (b) standard severe (n=161; aortic valve area, ≤1 cm(2); mean gradient ≥40 mm Hg), and (c) paradoxical severe (n=141; aortic valve area, ≤1 cm2 and mean gradient <40 mm Hg). Additive Euroscore was 7 ± 3. The association of LV-GLS with all-cause mortality was assessed after risk-adjustment using Cox proportional hazards models. Median LV-GLS was -14.8% (interquartile range, -17.2%, -12.1%). At 4.4±1.4 years, there were 92 (23%) deaths. On multivariable Cox analysis, additive Euroscore (hazard ratio, 1.19; 1.13-1.27; P<0.001), New York Heart Association class (hazard ratio, 1.44; 1.11-1.87; P<0.001), AV surgery with time-dependent covariate analysis (hazard ratio, 0.29; 0.19-0.45; P<0.001), and LV-GLS (hazard ratio, 1.05; 1.03-1.07; P<0.001) were independent predictors of mortality. LV-GLS <-12.1% (4th quartile) was associated with significantly reduced survival. Addition of LV-GLS to clinical parameters (additive Euroscore+New York Heart Association class) led to significant improvement in prediction of mortality (χ(2) increased from 48 to 58; P<0.01).

CONCLUSIONS: LV-GLS independently predicts mortality in moderate-severe and severe AS patients with preserved LV ejection fraction, providing incremental prognostic utility, in addition to standard clinical and echocardiographic parameters.