Occult Cocaine- and Alcohol-Induced Cardiomyopathy, Aorto-Ostial Thrombus, and Intracardiac Shunting in an Inferior STEMI.

BACKGROUND: Inferior ST-segment elevation myocardial infarction from right coronary artery (RCA) occlusion typically causes isolated right ventricular infarction with preserved left ventricular function. Disproportionate biventricular failure should prompt evaluation for an underlying cardiomyopathy. CASE SUMMARY: A 58-year-old man presented with inferior ST-segment elevation myocardial infarction, cardiogenic shock, and refractory hypoxemia. Coronary angiography could not engage the RCA ostium, and computed tomography revealed complete aorto-ostial RCA occlusion with a thrombus protruding into the aortic root, precluding revascularization. Severely reduced left ventricular function suggested pre-existing cardiomyopathy. Venoarterial extracorporeal membrane oxygenation was initiated as a bridge to decision. Only after cannulation was daily cocaine and alcohol use discovered, explaining the cardiomyopathy and precluding transplantation. The family withdrew life-sustaining therapy. DISCUSSION: Three compounding mechanisms-occult substance-use cardiomyopathy, cocaine-induced thrombosis, and probable intracardiac shunting-converted a typically survivable infarction into an irreversible cardiac collapse. TAKE-HOME MESSAGE: Disproportionate biventricular dysfunction should trigger a cardiomyopathy workup, and mechanical circulatory support requires a predefined exit strategy established before cannulation.