Background and Objectives：The objective of this study was to find the possivility for quantification of ventricular dyssynchrony by analsis of myocardial velocity curve obtained with Doppler myocardial imaging (DMI) in patients with advanced heart failure.
Subjects and Methods：Doppler myocardial images at the apical 4 chamber and 2 chamber views were recorded in 28 patients with a left ventricular ejection fraction (LVEF) <45%, and in 18 normal controls. Time intervals from the onset of the QRS complex to the peak systolic velocity were measured at the mid-portion between the basal and mid segments of 4 different ventricular walls (septal, lateral, inferior and anterior)；their maximal differences (DIFF) and standard deviation (STD) were calculated and compared.
Results：There were significant differences in the LVEF (30±8 vs. 63±4%, p<0.05) and QRS durations (117±35 vs. 92±9 msec, p<0.05) between the heart failure and control groups. The mean values of DIFF in the heart failure and control groups were 73±32 and 14±6 msec, respectively (p= 0.001). The DIFF and STD showed negative correlations with the LVEF (r=-0.773 with DIFF, r=-0.771 with STD, p<0.001) and positive correlations with the QRS duration (r=0.51 with DIFF, r=0.498 with STD, p<0.001). Fifteen of the patients with heart failure (54%) showed a QRS duration <110 msec；although their QRS duration was not significantly different from that of the normal controls (93±12 vs. 92±9 msec, p>0.05), but the DIFF, from the DMI, was significantly prolonged (61±35 vs. 14±6 msec, p=0.001). The QRS duration showed no significant correlation with the LVEF in the patients with a QRS duration <120 msec (r=-0.276, p= 0.103), but the DIFF showed a significant negative correlation in these patients (r=-0.769, p=0.001).
Conclusion：The DIFF and STD, as measured by DMI, are useful in the quantification of ventricular asynchrony, and correlated with other indices known to reflect the left ventricular systolic function.
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