Objective To analyze the relation between ischemic mitral regurgitation (IMR) and the changes of left ventricular systolic synchrony and volume parameters before and after percutaneous coronary intervention (PCI) in patients with subacute myocardial infarction and to evaluate the impact of PCI on IMR by measuring such changes with three-dimensional echocardiography volume quantitation technology. Methods Eighty-seven patients were enrolled and echo data were acquired before and 6 months after PCI. Patients were classified into alleviation group (group Ⅰ) and non-alleviation group (group Ⅱ) according to the change of mitral regurgitation volume (MRvol). The systolic synchrony indexes (Tmsv 16-SD%, Tmsv 16-Dif%) and left ventricle volume parameters (LVEDVI and LVESVI) before and after PCI for patients of two groups were measured and contrasted. Results Systolic synchrony indexes of all patients of two groups were improved after PCI. Left ventricular volume parameters were decreased after PCI in group Ⅰ, and the remodeling was reduced. Correlation analysis of the parameters variations showed that, there was significant positive correlation between variations of left ventricular volume and MRvol in all patients and no significant correlation between variation of systolic synchrony index and MRvol. Conclusions PCI can improve left ventricular systolic dyssynchrony for submyocardial infarct patients. Left ventricular volume index that reflects the remodeling process is closely related to IMR. Key words: Echocardiography, three-dimensional; Myocardial infarction; Mitral valve insufficiency; Ventricular function, left; Stents