The aim of the study was to compare similar time-movement (TM) and tissue Doppler (TDI) timing parameters and to predict their value in assessment of systolic asynchrony for biventricular pacing indication.
Methods: 41 patients (pts) aged 56.4 +/- 11.2 years with dilated cardiomyopathy were included.
Parameters: QRS duration (QRSd); septal (S), posterior (P), lateral (L) and posterolateral (PL) wall delays, as the time from QRS onset to maximal wall contraction (parasternal, 4 chamber view and subcostal incidence); left ventricular mechanical delays (LVD) time interval from maximal contraction between interventricular septum and posterior (LVDp), lateral (LVD1) and posterolateral (LVDp1) wall, both in TM and TDI; TDI measurements were performed using both color and pulsed TDI (from onset of QRS to the end of S wave); isovolumic relaxation time (IRT) in each wall using TDI; An error parameter (Er) was assessed for each measurement as the difference in similar timing parameters TM-TDI.
Results: LVDp = 111 +/- 69ms, LVD1 = 132 +/- 62ms, LVDp1 = 151 +/- 77ms; 26 pts presented QRSd > 120 ms (LBBB), 15 pts had QRSd < 120 ms. LVD > 100 ms was found in 32 pts; LVD were significantly higher in LBBB pts. There was no correlation between QRSd and echocardiographic parameters. Er ranged from 0-80 ms. Er > 30 ms were found in pts with fragmented wall motion and IRT > 30 ms. The most delayed wall was PL (42% pts), L (38%) and P (30%).
Conclusion: Intraventricular asynchronized contraction occurs even in pts with normal QRS duration; these changes can be easily and accurately detected using simple TM timing parameters. The most delayed site to be stimulated can be found either using TDI or TM.