Society of cardiac angiography and interventions: suggested management of the no-reflow phenomenon in the cardiac catheterization laboratory.

The interventional cardiologist makes a provisional diagnosis of the no-reflow phenomenon in the presence of an acute reduction in coronary flow despite a widely patent epicardial vessel during percutaneous coronary intervention (PCI). Its occurrence is recognized as a column of contrast arising distal to the original target stenosis that does not rapidly clear [1–3]. The precise pathophysiologic mechanisms are uncertain, although flow-limiting spasm of the distal microvasculature, distal thromboembolism, and microembolization of atherosclerotic debris are believed to be operative, in some combination, in most cases [4,5]. No-reflow as a cardiac phenomenon was originally identified in experimental models of acute myocardial infarction and described as the failure to restore normal myocardial blood flow despite subsequent removal of the coronary arterial obstruction, attributable to microvascular damage related to irreversible ischemic changes and local edema. It has been recognized for over a decade clinically [6,7] as an uncommon (0.6–2.0%) complication of PCI [1,2,6]. It occurs frequently following thrombolytic or mechanical reperfusion for acute myocardial infarction and in the setting of unstable angina [3,7,8]. It is most common during use of rotational atherectomy [9,10] and during PCI in saphenous vein grafts [2]. The purpose of this review is to define the angiographic appearance and clinical outcomes of no-reflow and to summarize the various treatment and prevention options currently available to the interventional cardiologist.