Association of left ventricular diastolic function with systolic dyssynchrony: a population study

Abstract

Left ventricular (LV) (dys)synchrony has an important impact on LV function and structure. Our study aimed to describe the distribution and determinants of LV mechanical delay indexes in the general population and to assess an association of different Doppler indexes reflecting LV diastolic function with LV mechanical delay indexes. In 200 subjects enrolled in a family-based population study (46.5% women; mean age, 57.9; 48% hypertensive), we performed echocardiography with tissue synchronization imaging (TSI) and two-dimensional speckle tracking. We measured the maximum difference in time to peak systolic velocity between any 2 of 12 LV segments (Ts-max); the standard deviation of time to peak systolic velocity of 12 segments (Ts-sd); the difference in time to peak systolic velocity and strain between septal and lateral LV walls and the strain delay index in septal and lateral walls [septal and lateral (SDI)]. In univariable and multivariable regression analyses, TSI indexes and lateral SDI independently increased with age (P ≤ 0.027) and body mass index (P ≤ 0.010). Ts-max and Ts-sd also increased with female sex (P ≤ 0.0002) and decreased with heart rate (P ≤ 0.0004). Septal SDI only increased with female sex (P < 0.0001). Among the Doppler indexes of LV diastolic function, only E/e' was significantly and positively associated with TSI indexes (P ≤ 0.037) and lateral SDI (P = 0.0026), but not with septal SDI (P = 0.69). In participants with advanced stage of LV diastolic dysfunction, TSI indexes were prolonged compare with subjects with normal LV diastolic function (P ≤ 0.002). We demonstrated that in unselected subjects LV diastolic dysfunction was associated with mechanical LV dyssynchrony as assessed by echocardiography.