ObjectiveTo investigate the correlation between myocardial perfusion and coronary endothelial injury in angina patients. MethodsCoronary stenosis was identified in 30 patients with angina pectoris. Coronary heart disease was excluded in 18 control patients. Blood samples were collected during coronary angiography. The concentrations of nitric oxide (NO),endothelin (ET) and the number of circulating endothelial cells (CEC) in coronary sinus blood were measured to mirror the coronary endothelial injury and dysfunction. Myocardial contrast echocardiography (MCE) was then performed. The images were estimated visually with score on the segmental myocardial perfusion situation. The contrast peak intensity,time to peak intensity (TP) and area under the curve (AUC) of MCE were then analyzed quantitatively by time-intensity curve obtained by equipment attached software. ResultsIn angina patients,especially in unstable angina patients,NO concentration in coronary sinus blood was lower,while ET concentration and CEC number were markedly higher than those in control group(P<0.05). The contrast peak intensity,TP,AUC of MCE showed markedly difference between unstable angina and stable angina patients. ET and CEC had negative correlation with MCE,and NO showed positive correlation with MCE. ConclusionMCE is closely associated with coronary endothelial injury. The combinaton of the two may describe the lesion of coronary artery and evaluate the prognosis of patients with coronary heart disease more satisfactorily.