Objective To assess the left ventricular (LV) systolic synchrony in patients with myocardial infarction using real-time three dimensional echocardiography(RT-3DE) and speckle tracking imaging(STI). Methods Twenty-five healthy subjects and thirty patients with myocardial infarction underwent two-dimensional echocardiography and RT-3DE examination. The systolic synchrony parameters derived from RT-3DE were the dispersion of time and the maximum difference of time to minimum regional volume for 16 LV segments (Tmsv-16-SD and Tmsv-16-Dif). When the Tmsv-16-SD was above the percent 99 of the control group distribution in patients with myocardial infarction were considered statistically different from those in the control group and were accordingly classified as LV systolic asynchrony. The time from the onset of QRS complexes to systole peak strain from the radial vectors was recorded using STI. The standard deviation and the maximal temporal difference of the radial (TRS-SD and TRS-Dif) of 18 segments were calculated as indicator of LV systolic synchrony. LV systolic asynchrony was defined as an interval≥130 ms for the absolute difference in time to peak radial strain for the anteroseptal wall versus the posterior wall (TAS-POST). Results All the systolic synchrony parameters derived from RT-3DE and STI were significantly larger in the myocardial infarction group than those of the control group (all P＜0.01 ).For Tmsv-16-SD and Tmsv-16-Dif,a moderate correlation with TRS-SD and TRS-Dif( r = 0.675 and 0.620,all P＜0.01) was found. No significant difference and general consistency were found between the systolic asynchrony parameters by RT-3DE and STI ( P = 0.125, Kappa = 0.60). Conclusions RT-3DE and STI provide effective tools to assess the LV systolic synchrony. There is no obvious correlation between these methods, thus it is essential of using different methods and parameters to evaluate the LV systolic synchrony.