This case report describes a 76-year-old man with paroxysmal atrial fibrillation who presented with inferolateral STEMI due to a distal thrombotic occlusion with otherwise nonobstructive coronary disease, and suspected coronary embolism was considered the most likely mechanism, highlighting the diagnostic challenge of this entity.
A 76-year-old man with paroxysmal atrial fibrillation presented with acute substernal chest pain and inferolateral STEMI.
Coronary angiography showed a 100% thrombotic occlusion of the distal right posterolateral ventricular branch with otherwise nonobstructive coronary artery disease.
Coronary embolism was considered the most likely mechanism of the STEMI.
The patient was continued on long-term anticoagulation and remained asymptomatic at 1-month follow-up.
Coronary embolism is an underrecognized nonatherosclerotic cause of STEMI, most commonly associated with atrial fibrillation, and diagnosing it is challenging.
This case report describes a 76-year-old man with an irregular heart rhythm called paroxysmal atrial fibrillation who came to the hospital with sudden chest pain and a heart attack of the STEMI type, which involves a blocked heart artery. Imaging of his heart arteries showed a complete blockage by a blood clot in a small, far-end branch, while the rest of his arteries had little cholesterol buildup. Because the blockage was abrupt, his arteries were otherwise fairly healthy, and he had atrial fibrillation, the doctors concluded that a clot that formed elsewhere (likely in the heart) and traveled into the coronary artery, known as coronary embolism, was the most likely cause. His case also met a set of diagnostic criteria known as the Shibata criteria. He continued long-term blood-thinning (anticoagulant) treatment and had no symptoms at one month. This research suggests that heart attacks in people with atrial fibrillation and few artery blockages may sometimes be due to clots traveling to the heart arteries rather than usual artery disease. As a single case with short follow-up and a presumed rather than proven cause, it cannot show how common this is or which treatment is best.
Gopannagari S, Manikanta Achuta K, Kirti I, Dabaja A, Kambhatla S. (2026). Inferolateral ST-Segment Elevation Myocardial Infarction Secondary to Suspected Coronary Embolism in a Patient with Paroxysmal Atrial Fibrillation: A Case Report.. International medical case reports journal. https://doi.org/10.2147/IMCRJ.S656587