Evaluation of left ventricular dyssynchrony using combined pulsed wave and tissue Doppler imaging

Introduction: The combination of pulsed wave (PW) and tissue Doppler imaging (TDI) has been proposed as a new method to assess left ventricular (LV) mechanical dyssynchrony (LVMD), but results have not been validated. We investigated the correlation of a combination of PW and TDI with a positive response to cardiac resynchronization therapy (CRT). Material and methods: We studied 108 consecutive patients who received CRT. Patients with atrial fibrillation were excluded. The time difference (T_PW-TDI) between onset of QRS to the end of LV ejection by PW (T_PW) and onset of QRS to the end of the systolic wave in LV basal segments with greatest delay by TDI (T_TDI) was measured before CRT and during short-term and long-term follow-up. Results: The T_PW-TDI interval before CRT was 74 ±48 ms. Intra-observer variabilities for T_PW and T_TDI were 1.5 ±0.24% and 1 ±0.17%. Inter-observer variabilities for T _PW and T_TDI were 1 ±0.36% and 1 ±0.64%, respectively. T_PW-TDI > 50 ms was defined as the cutoff value for diagnosis of LVMD by receiver operating curve (ROC) analysis. During follow-up of 15 ±11 months, the sensitivity and specificity of TP_PW-TDI to predict a positive response to CRT were 98% and 82%, respectively. The area under the ROC curve was 0.92. There was a significant agreement between LVMD determined by T_PW-TDI and the positive response to CRT (κ = 0.80). Conclusions: Left vertricular dyssynchrony detected by the method combining PW and TDI demonstrated a high reproducibility, sensitivity, specificity and agreement with a positive response to CRT.