Physiological range of mechanical synchronicity of the human heart: comparison between different echocardiographic assessment modalities.

ABSTRACT

Tissue Doppler was performed to assess physiological ranges of mechanical synchronicity in 47 patients aged 38 to 81 y with normal coronary angiograms, ECG recordings and echocardiographic findings. Maximal time delays between two different left ventricular (LV) walls in long axis time-to-peak tissue displacement (TD_D), respectively in time-to-peak strain (TD_S), time-to-peak strain rate (TD_SR), time-to-peak systolic (TD_VS) and early diastolic (TD_VE) velocities of basal and midwall segments were determined as values corrected for heart rate in a 16-segment LV model and in the right ventricle (RV). Strain (TD_S LV = 212 +/- 108 ms, RV = 195 +/- 15 ms) and strain rate (TD_SR LV = 183 +/- 67 ms, RV = 120 +/- 60 ms) showed the highest dyssynchrony values (TD_D LV = 110 +/- 96 ms, RV = 42 +/- 38 ms; TD_VS LV = 82 +/- 47 ms, RV = 36 +/- 36 ms; TD_VE LV = 73 +/- 36 ms, RV = 46 +/- 20 ms) in both ventricles. There was no significant association between a certain LV wall and the occurrence of the earliest, respectively latest peak values of any parameter.