Inter- and intraobserver consistency in LV myocardial strain measurement using a novel multi-layer technique in patients with severe aortic stenosis and preserved LV ejection fraction

Abstract

BackgroundA new transthoracic echocardiography (TTE) technique allows multi-layer measurement of left ventricular (LV), endocardial, epicardial, and whole layer myocardial strain. We evaluated interobserver and intraobserver TTE reproducibility for 2D LV global longitudinal (GLS) and circumferential strain (GCS) estimates using data from severe aortic stenosis (AS) subjects with preserved LV ejection fraction (EF). MethodsTwenty severe AS subjects (11 male; mean age, 75±7years; LV EF >50%) underwent TTE (Vivid E9, GE Healthcare). Quantitative strain measurements of whole, endocardial, and epicardial layers were performed. GLS was defined as all 17 averaged LV segments, according to the American Heart Association classification. GCS was measured at the levels of the mitral valve, papillary muscle, and apex. ResultsInterobserver correlation coefficients in whole, endocardial, and epicardial layers for GLS estimates were 0.81, 0.83, and 0.80, respectively, whereas those for GCS estimates were 0.38, 0.56, and 0.19, respectively, for the mitral valve, 0.44, 0.54, and 0.36, respectively, for the papillary muscle, and 0.55, 0.29, and 0.59, respectively, for the apex. Intraobserver correlation coefficients in whole, endocardial, and epicardial layers for GLS estimates were 0.97, 0.97, and 0.94, respectively, whereas those for GCS estimates were 0.86, 0.81, and 0.50 , respectively, for the mitral valve, 0.56, 0.72, and 0.28, respectively, for the papillary muscle, and 0.70, 0.69, and 0.62, respectively, for the apex. ConclusionIn severe AS subjects with preserved LVEF, inter- and intra-observer TTE reproducibility in whole, endocardial, and epicardial layers were more consistent for 2D LV GLS than for 2D LVGCS.