Non-ST-Segment Elevation Myocardial Infarction Secondary to Embolic Prosthetic Valve Thrombus: A Rare Post-Transcatheter Aortic Valve Replacement Complication

Background: Acute coronary syndrome (ACS) is most often caused by plaque rupture, but embolic thrombi from cardiac structures such as prosthetic valves represent a rare and underrecognized etiology. Case Summary: An 82-year-old female with a prior transcatheter aortic valve replacement presents with non-ST-elevation myocardial infarction. Coronary angiography revealed a thrombus extending from the distal left main into the left circumflex artery, successfully treated with aspiration thrombectomy and angioplasty. Transesophageal echocardiography showed no thrombus, but cardiac CT revealed thrombi on all 3 prosthetic valve cusps. She was started on long-term anticoagulation. Discussion: This case illustrates prosthetic valve leaflet thrombosis as an unusual cause of embolic ACS. It highlights the limitations of transesophageal echocardiography in detecting leaflet thrombus and the superior diagnostic value of cardiac computed tomography. Take-Home Messages: Clinicians should consider valve thrombosis in embolic ACS and recognize cardiac CT as the preferred imaging modality. Further studies are needed to guide anticoagulation strategy.