Intracoronary pharmacotherapy in the management of coronary microvascular dysfunction.

Although percutaneous coronary intervention restores optimal epicardial blood flow in most cases, abnormal myocardial perfusion may still persist. This might be as a result of macro and microembolization, neutrophil plugging, vasoconstriction, myocyte contracture, local intracellular and interstitial edema, intramural haemorrhage, and endothelial blistering. Local delivery of intracoronary pharmacotherapy via the coronary arteries may increase local drug concentration several fold, and may improve drug efficacy. Several pharmacological agents such as adenosine, calcium channel blockers, alpha blockers, beta2 receptor activators, vasodilators, antithrombotics, and antiplatelet agents have been used to treat coronary microvascular dysfunction. This article reviews the results of trials of intracoronary pharmacotherapy to date.