Quantitative analysis of myocardial perfusion in patients with coronary slow flow by real-time myocardial contrast echocardiography

Objective To discuss the clinical value of real-time myocardial contrast echocardiography(RT-MCE) on quantitative assessing myocardial perfusion in patients with coronary slow flow(CSF). Methods CSF group contained 14 patients with CSF and 15 cases with normal coronary angiography (CAG) were involved as control group. The 2D echocardiography and RT-MCE images from standard 3 apical views (4-chamber, 2-chamber, and long-axis) were acquired. All images were digitally stored on hard disks for offline analysis by QLab software. The RT-MCE parameters included myocardial blood volume(A), myocardial blood veloity(β), myocardial blood flow(MBF) were used to predict the impairment of myocardial perfusion in the two groups. Results In CSF group, the value of β and MBF in abnormal segments were significantly lower than those in normal segments (P 0.05). Compared to the control group, the value of β and MBF were significantly lower in abnormal segments of CSF group(P 0.05). ROC curve analysis showed the AUC of β was the biggest (AUC=0.867, P<0.001), and when the cut-off value was 1.34, the impairment of myocardial microcirculation was best predicted (sensitivity, 79.6%; specificity, 77.4% ). Conclusions The myocardial perfusion in patients with CSF can be appraised by RT-MCE quantitatively. The value of β can identify the early impairment of myocardial microcirculation perfusion in patients with CSF and has the promising prospect of clinical diagnosis. Key words: Echocardiography; Coronary disease; Myocardial microcirculation; Myocardial perfusion