No reflow phenomenon in coronary heart disease

Prolonged myocardial ischemia often damages myocardium profoundly, and flow to the previously ischemic myocardium is significantly reduced, which is called the "no reflow" or "low reflow" phenomenon. Myocardial contrast echocardiography (MCE) shows that a not insignificant number of patients with acute myocardial infarction have a substantial no reflow phenomenon. Our studies have demonstrated that patients with MCE-no reflow have larger myocardial infarctions, poorer functional outcomes, more frequent complications, and left ventricular remodeling and higher mortality compared with those with MCE-reflow. MCE-no reflow is also the main cause of slow flow after coronary intervention for acute myocardial infarction. We can now improve microvascular function with adjunctive pharmacological intervention. Intracoronary verapamil and intravenous infusion of nicorandil in conjunction with reperfusion therapy augment myocardial perfusion and are associated with better functional and clinical outcomes compared with coronary reperfusion alone. Study of myocardial perfusion with MCE provides useful information for predicting the success of reperfusion therapy at the microcirculation level and the impact of pharmacological intervention on acute myocardial infarction.