Prediction of Long-term Response to Cardiac Resynchronization Therapy by Real-time Three-dimensional Echocardiography / 中国医科大学学报

Objective To evaluate the value of real-time three-dimensional echocardiography（RT3DE）to predict the long-term response to cardiac resynchronization therapy（CRT）.Methods Twenty-six patients with heart failure were scheduled for CRT.RT3DE was performed before and one year after the pacemaker implantation,and left ventricular（LV）dyssynchrony was defined as the maximum difference（Tmsv 16-Dif）and standard deviation（Tmsv 16-SD）when the minimum systolic volume of 16 segments was reached.Patients were divided into re-sponders and non-responders according to a reduction ≥15 % in LV end-systolic volume（LVESV）after CRT.Results Seventeen patients（65.4 %）were classified as responders.Compared with non-responders,the responders demonstrated a significant increase in LV ejection fraction,and reduction in Tmsv 16-SD.Tmsv 16-SD was a determinant factor for Δ LVESV ≥15%.Tmsv 16-SD 〉3.5% could be employed to evaluate the short-term response to CRT with 80 % sensitivity and 77 % specificity.Conclusions CRT can increase the LV systolic function and synchrony.RT3DE is highly predictive for long-term response to CRT

Evaluation of left ventricular dyssynchrony with two-dimensional speckle tracking echocardiography in acute myocardial infarction / 中国医学影像技术

Objective To evaluate the left ventricular (LV) systolic dyssynchrony after the acute myocardial infarction (AMI) with two-dimensional speckle tracking echocardiography (STE). Methods STE were performed in 65 patients within 72 h of AMI and compared with 60 age- and sex-matched healthy volunteers. The peak longitudinal strain (LS_(peak)) was measured at LV myocardium. LV dyssynchrony 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). Size of myocardial infarction (MIS)was confirmed by wall-motion score index (WMSI). Results The LS_(peak) and LV ejection fraction (LVEF) were lower, and WMSI and TAS-POST were larger in AMI patients compared with controls. Forty-two patients had developed LV dyssynchrony (64.62%), and there were strong correlation between LV dyssynchrony (TAS-POST) and LS_(peak), LVEF, and WMSI (MIS). MIS was the most independent predictor for systolic dyssynchrony. Conclusion AMI with normal QRS can induce LV dyssynchrony, which is mainly determined by MIS. STE is a reliable technique for accurate evaluation of LV synchrony.