Usefulness of triplane tissue Doppler imaging to predict acute response to cardiac resynchronization therapy

This study evaluated the value of triplane tissue Doppler imaging (TDI) to predict acute response after cardiac resynchronization therapy (CRT). Forty-nine patients scheduled for CRT underwent triplane echocardiography with simultaneous TDI acquisition before and 48 hours after implantation. A 3-dimensional left ventricular (LV) volume was generated and LV volumes and ejection fraction were calculated. A parametric imaging technique, tissue synchronization imaging, was applied to portray the area of latest mechanical activation. LV dyssynchrony was quantitatively analyzed by evaluating time from QRS onset to peak myocardial velocity in 12 LV segments from the triplane dataset. Acute response was defined as > or =15% decrease in LV end-systolic volume. Receiver-operating characteristic curves of dyssynchrony parameters were analyzed to identify predictors of response to CRT. Acute response was observed in 47% of patients. Responders had a significantly larger extent of LV dyssynchrony at baseline compared with nonresponders. Optimal prediction of acute response to CRT was obtained with the SD of time delays in all LV segments (sensitivity 91%, specificity 85%). In conclusion, 3-dimensional TDI echocardiography permits parametric and quantitative analyses of LV dyssynchrony and assessment of LV volumes and ejection fraction. LV dyssynchrony parameters, derived from the triplane TDI dataset, were highly predictive for acute volumetric response to CRT.