Left ventricular systolic synchrony in dilated cardiomyopathy patients with normal QRS wave

Abstract

To evaluate the distribution characteristics of left ventricular systolic dyssynchrony (LV-SD) in dilated cardiomyopathy (DCM) patients with chronic heart failure (CHF) and normal QRS wave width, by pulsed-wave Doppler tissue imaging (PW-DTI), and study its relation with left ventricular systolic function, ventricular remodeling, and functional mitral regurgitation (FMR). The time to peak systolic velocity (Ts) in 12 left ventricular segments was evaluated by PW-DTI, from which the standard deviation (SD) of Ts in the 12 segments (Ts-SD) and maximum Ts difference (Ts-maxD) were calculated. Ts-SD and Ts-maxD in the 12 LV segments of the DCM patients with CHF were significantly higher than those of the healthy controls (P<0.01). In DCM patients with CHF and normal QRS wave width, the incidence of LV-SD was 29.8% (14/47) and the inferior wall was the most frequent distribution site of contraction delay. Linear regression analysis revealed a negative correlation between Ts-SD, Ts-maxD, and left ventricular ejection fraction (LVEF) (P<0.01), but a positive correlation between Ts-SD, Ts-maxD and left ventricular end-diastolic volume (LVEDV), lefe ventricular end-systolic volume (LVESV), New York Heart Association (NYHA) cardiac function, FMR (P<0.01) in DCM patients with CHF. LV-SD exists in DCM patients with normal QRS width. LV-SD aggravates the LV systolic function damage, which is closely associated with left ventricular remodeling. LV-SD may contribute to the FMR in DCM patients.