Coronary No-Reflow Phenomenon in Clinical Practice

Timely delivered coronary revascularization with no residual anatomical stenosis does not always lead to prompt restoration of anterograde coronary flow and complete myocardial reperfusion. This condition is known as coronary no-reflow and is associated with major clinical adverse events and poor prognosis. The pathophysiology of no-reflow phenomenon is still poorly understood. Proposed mechanisms include distal microembolization of thrombus and plaque debris, ischemic injury, endothelial dysfunction and individual susceptibility to microvascular dysfunction/obstruction. Older age, diabetes, hypercholesterolemia, prolonged ischemic time, hemodynamic instability, high thrombus burden, complex angiographic lesions and multivessel disease are frequently reported to be associated with the no-reflow phenomenon. There is no general consensus on the correct prevention and management of no-reflow. Non-pharmacological measures such as distal embolic protection devices and manual thrombus aspiration did not result in improved flow or reduction of infarct size. Current preventive measures include reduction of time from symptoms onset to reperfusion therapy, and intracoronary administration of vasodilators such as adenosine, verapamil or nitroprusside.