Relationship of multidirectional myocardial strain with radial thickening and ejection fraction and impact of left ventricular hypertrophy: a study in a community-based cohort.

BACKGROUND: Left ventricular (LV) systolic strain provides additional prognostic value to LV ejection fraction (LVEF) and wall motion analysis. However, the relationship between myocardial multidirectional strain and LVEF, and the effect of LV hypertrophy on this relationship, are not completely understood especially in unselected populations.

METHODS: LV global longitudinal (εL ) and circumferential (εC ) systolic strain analysis was performed by two-dimensional speckle tracking echocardiography in 215 participants from a community-based study. LV radial wall thickening was measured as global radial strain (εR ), and LVEF was assessed by biplane Simpson's method.

RESULTS: εR was significantly associated with εC (β = -0.56, P < 0.01) and with εL (β = -0.18, P < 0.01). The contribution of εL to εR was especially evident in subjects with lower εC and in presence of LV hypertrophy (β = -0.30, P < 0.01). εL and εC were significantly associated with LVEF (β = -0.36 and β = -0.49, both P < 0.01) independent of LV mass and other confounders, and their interaction significantly improved the prediction of LVEF (R(2) -change = 0.14) but not of εR (R(2) -change = 0.002).

CONCLUSIONS: εR is mainly related to εC with a smaller contribution of εL , which becomes especially evident in subjects with lower εC and in presence of LV hypertrophy. Therefore, radial thickening may not detect subclinical LV longitudinal function reduction in normal ventricles and when εC is preserved. While a reduction in εL has a limited impact on εR , it exerts a greater effect on global LVEF, therefore for a more accurate LVEF prediction both εL and εC need to be considered.