Abstract

Background: The aim of this study was to propose modified tissue Doppler imaging (TDI) parameters derived from the first active wall motion and to assess them for the better prediction of cardiac resynchronization therapy (CRT) responders in comparison with to original TDI parameters. Methods and Results: In 61 patients with CRT, time from QRS onset to peak velocities by TDI (Ts), which were derived from active wall motion identified by longitudinal strain rate (LSR) value, were assessed. Time from QRS onset to the negative peak of LSR (TLSR) was also assessed. Modified standard deviation of Ts in 12 left ventricular (LV) segments (Ts-SD), that of TLSR (TLSR-SD), differences of Ts between septum and lateral wall (Ts-SL), and that of TLSR (TLSR-SL) were calculated. Original Ts-SD and Ts-SL were calculated by previously described methods. Responders were defined as patients with LV end-systolic volume reduction (>15%) at 6 months after CRT: 35 patients (57%) were identified as CRT responders. Area under the receiver-operating characteristics curve (AUC) of modified Ts-SD (0.87) was significantly higher than that of Ts-SD (0.65), Ts-SL (0.62), and TLSR-SL (0.69). AUC of modified Ts-SL was significantly higher than those of Ts-SD, and Ts-SL. AUC of TLSR-SD (0.82) also was significantly higher than that of Ts-SD. Conclusions: Modified TDI dyssynchrony parameters derived from the first active wall motion improve the ability to predict responders to CRT.