BACKGROUND: Ultrasound can be used to quantitatively assess cardiac mechanical dyssynchrony. The differences between and prognoses of chronic heart failure (CHF) patients with left heart dysfunction and remodeling for different combinations of intra-left ventricular (intra-LV) and interventricular (inter-V) mechanical dyssynchrony or synchrony remain unclear. This study sought to assess the relationships among intra-LV dyssynchrony, inter-V dyssynchrony, and left heart function and remodeling in CHF patients. METHODS: CHF patients with a left ventricular (LV) ejection fraction <
50% and control subjects presenting with no abnormalities in their medical history or on physical examination, electrocardiography, or echocardiography during the concurrent physical assessment were retrospectively included in the study. The patients were divided into four groups based on the standard deviation of the time to peak longitudinal strain in 12 LV segments according to speckle-tracking echocardiography (SD RESULTS: In total, 52 control subjects (60.79±13.3 years, 32 males) and 208 patients (59.9±12.6 years, 160 males) were included in the study. Of the subjects, 58 had intra-LV and interventricular synchrony (Intra CONCLUSIONS: Compared with IVMD, intra-LV dyssynchrony is more strongly associated with LV dysfunction and remodeling in CHF patients, and LA dysfunction is predominantly contingent upon/is largely dependent on LV dysfunction. When both intra-LV and inter-V dyssynchrony are present, the extent of the LV volumetric increase and electrical remodeling is the most pronounced. This patient group had a higher incidence of cardiac events during follow up and a greater likelihood of receiving CRT.