Introduction: The use of tissue velocity and strain rate imaging is proposed for the quantification of non-viable myocardium. This study is aimed at investigating the differences in tissue velocity and strain rate imaging indices between non-viable left ventricular apical segments and the normal segments using segment-by-segment comparison.Materials and Method: Thirty-two patients with akinetic left ventricular apical segments and without viability were selected using two-dimensional echocardiography and dobutamine stress echocardiography; 32 individuals with normal echocardiography and coronary angiography formed the normal group. Peak systolic velocity, peak systolic strain, and strain rate were measured in the four left ventricular apical segments and the apex 17th segment.Results: The patient group had a significantly lower ejection fraction (26.88±6.06% vs. 56.56±2.36%; p<0.001). Overall, the patient group had significantly lower resting peak systolic velocity, systolic strain, and strain rate. In the segment-by-segment comparison, only systolic strain showed a remarkable reduction in the patient group, while reduction in Sm and strain rate were not significant in all the segments. After dobutamine stress echocardiography, only systolic strain showed an insignificant increase compared to the resting values. In the apex 17th segment, Sm showed significant reduction in the patient group.Conclusion: The ST in apical segments may be used as a quantitative index for detecting akinesia both at rest and after dobutamine infusion. Reduction in Sm can be used as a marker of akinesia in the apical cap at rest.
549 Comparative study of angle-corrected tissue velocity, displacement, strain and strain rate imaging to characterize mechanical dysynchrony in left bundle branch block
