PFO-Mediated Paradoxical Coronary Embolism Causing Myocardial Infarction: Concordant Imaging Findings

Paradoxical coronary embolism is a rare cause of myocardial infarction in which establishing causality may be challenging without an identifiable venous thromboembolic source.

A 36-year-old man presented with chest pain and elevated troponin. Coronary angiography demonstrated distal thrombotic occlusion of the right posterolateral ventricular branch within an otherwise smooth coronary tree without significant atherosclerosis. Cardiac magnetic resonance showed subendocardial-to-transmural infarction with edema confined to the corresponding vascular territory. Transthoracic and transesophageal echocardiography demonstrated a patent foramen ovale (PFO) with right-to-left shunting, and no alternative embolic source was identified. Findings supported probable PFO-mediated paradoxical coronary embolism, and percutaneous closure was performed.

Concordant angiographic and cardiac magnetic resonance findings, together with echocardiographic demonstration of right-to-left shunting, supported probable paradoxical coronary embolism and guided conservative acute management followed by PFO closure.

Plaque-free distal coronary thrombus should prompt consideration of embolism. Multimodality imaging can support mechanism-informed diagnosis and secondary prevention.