Left Ventricular Longitudinal Systolic Function, Afterload and Contractility in Severe Aortic Stenosis

Abstract

Background: In patients with severe aortic stenosis (AS), left ventricular systolic longitudinal function (SLF) is impaired despitenormal ejection fraction (EF). However, similarly to other shortening indexes, SLF depends on afterload and its relationshipwith contractility has not been thoroughly studied.Objective: The aim of this study was to evaluate SLF alterations and their relationship with afterload and myocardial contractilityin patients with severe AS.Methods: One hundred and one patients with severe AS (AVA <1 cm2) and 63 normal control subjects were studied withDoppler echocardiography. Left ventricular systolic longitudinal function was evaluated by lateral mitral annulus systolicdisplacement (MASD) and peak S wave velocity (tissue Doppler imaging). Contractility was assessed by the midwall fractionalshortening (mFS)–end-systolic stress (ESS) relationship in control subjects. Contractility level (CL) was defined as measuredmFS minus predicted mFS for a defined ESS value.Results: Lateral mitral annulus systolic displacement and S wave correlated directly with shortening indexes as EF and mFSand inversely with afterload indexes as ESS. There was no correlation between SLF and CL. In the multivariate analysisESS and EF were predictors of SLF.Conclusions: In patients with severe AS, SLF correlated inversely with afterload. The presence of decreased MASD or S wavewas not associated with abnormal left ventricular contractility.