Assessment of left ventricular contractility in patients with severe aortic stenosis, low-flow, low-gradient and preserved ejection fraction

Abstract

Introduction: In patients with severe aortic stenosis (AS), low-gradient, low-flow, and preserved ejection fraction (EF) (≥ 50%) (LG/LFp) the decrease in stroke volume index (Svi) could be due to diminished contractility. The aim of this study was to analyze if low Svi in patients withLG/LFp is related to a decrease in contractility. Methods: Thirty patients with LF/LGp and 63 normal subjects were studied with Doppler echocardiography. The level of contractility (LC) was assessed by mean of midwall shortening fraction (mSF) -end-systolic stress relationship. Relative wall thickness (RWT) and aortic valve area (AVA) were calculated. Results: LC was diminished in 40% of LF/LGp patients. By bivariate analysis LC correlated with RWT and mSF. Svi correlated with AVA but not with LC. In multiple linear regression, RWT and mSF were predictors independents of LC. About Svi, AVA was the only predictor independent variable. Conclusion: Decreased contractility was present in 40% of LF/LGp patients despite preserved EF. LC had correlation with mSF and EPR. Low Svi appears to be related to AS severity rather than low contractility.