Abstract: Objective To assess the efficacy of cardiac resynchronization therapy using real-time three-dimensionsl echocflrdiography and speckle trackingimaging in patients with chronic heart failure. Methods Thirty patients with chronic heart failure were examined by RT-3DE and STI before CRT and 3，6months after CRT.Measured LVEDV、LVESV and LVEF.RT-3DE parameters were the dispersion of time to minimum regional volumefor 16 segments(Tmsvl6SD) and the ratio of Tmsvl6-SD to R-R interval and the maximum time difference(Tmsvl6-Dif).STl parameters were the ratios of standard deviation of the time to peak longitudinal radial and circumferential strainat to R-R intervaI(Tls-16SD% Trs-16SD%，Tcs-16SD%) from the beginning of Q wave of electrocardiography to the point atminimal systolic Volume of all 16segments and the maximum time difference 。Results The LVEDVand LVESVof 3，6months after CRT were smaller than that before CRT,The LVEF raised . The Tmsv-16SD%、Tmsvl6Dif%、Tls-l6SD%、Trs-l6SD%、Tcs-l6SD% and T-Dif% of 3，6months after CRT reduced than that before CRT, (P<0.05). The Tmsv-16SD% 、Tmsvl6Dif%、Trs-l6SD%、Tcs-l6SD% were negatively associated with LVEF. Conclusion Real-time three-dimensionsl echocflrdiography and speckle tracking imaging represents a promising novel technique for assessment of global LV function and dyssynchr.

Key words: heart failure, echocardiography, doppler, color, cardiac resynchronization therapy, real-time three-dimensional echocardiography, speckle tracking imaging