Myocardial Stunning Induced by Vasospasm Within an Intercoronary Communication

Intercoronary communication (ICC) is an extremely rare congenital coronary anomaly that is generally considered benign. We herein report a novel case in which an ICC itself caused coronary vasospasm, leading to myocardial ischemia.

A 79-year-old woman presented with rest angina. Transthoracic echocardiography revealed hypokinesia of the posterolateral left ventricular wall. Coronary angiography demonstrated an ICC between the left circumflex artery and right coronary artery, and acetylcholine-induced focal coronary vasospasm was provoked exclusively in the ICC and was relieved with intracoronary isosorbide dinitrate. The patient was treated with oral vasodilators, after which she remained symptom-free. Follow-up echocardiography showed complete recovery of wall motion.

This case illustrates a paradoxical scenario in which an ICC, typically considered as a "safety valve," instead caused localized vasospastic myocardial ischemia.

ICC itself may cause coronary vasospasm, resulting in myocardial ischemia.