Non-invasive analysis coronary artery flow velocity of slow coronary flow phenomenon

Abstract

Objective To non-invasive assess coronary blood flow velocity changes of patients with slow coronary flow phenomenon (SCFP) by coronary blood flow imaging (CFI).Methods Twenty-one patients who had no significant coronary artery stenosis but had thrombolysis in myocardial infarction (TIMI) slow-flow phenomenon were the experimental group,nine patients who has no significant coronary stenosis and TIMI flow normal were the control group.Using corrected TIMI frame count(CTFC) assess velocity of coronary artery.The left ventricular end diastolic diameter,end systolic diameter,ejection fraction,E peak velocity,A peak velocity,E/A ratio were measured by conventional echocardiography.The distal anterior descending coronary artery diastolic peak flow velocity(Vmax),mean velocity(Vmean) and blood flow velocity time integral(VTI) were measured by CFI.Results The corrected TIMI frame count (CTFC) of left anterior descending artery blood flow in slow blood group was (45.37 ± 8.62)frame,that in control group was (15.94± 4.66)frame,the difference was statistically significant (t = -9.596,P =0.000).The conventional echocardiographic measurements of two groups were not significantly different.The left anterior descending artery Vmax was (22.86 ± 3.04)cm/s,Vmean was (17.62 ± 2.89)cm/s,VTIwas (8.49± 2.01)cm in the slow blood flow group,the left anterior descending artery Vmax was (31.78 ± 9.28) cm/s,Vmean was (23.67 ± 7.60) cm/s,VTI was (10.91 ± 4.47) cm in the control group.The difference was statistically significant.The left anterior descending artery CTFC with Vmax and Vmean was negative correlation in the control group and the slow blood flow group.The left anterior descending artery CTFC was negatively correlated with VTI in the control group,there was no correlation between left anterior descending artery CTFC and VTI in the slow blood flow group.Conclusions Coronary artery flow velocity in the left anterior descending artery was declined.CFI can reflect changes in coronary TIMI flow,but in the diagnosis of coronary slow flow phenomenon CFI has limitations. Key words: Echocardiography; Coronary disease; Coronary slow flow phenomenon; Coronary blood flow imaging