Abstract 4339015: NSTEMI Secondary to Embolic Prosthetic Valve Thrombus: A Rare Post-TAVR Complication

Background: Non-ST-elevation myocardial infarction (NSTEMI) typically results from plaque rupture leading to obstructive coronary artery disease. However, embolic thrombi originating from cardiac structures, such as prosthetic valves, can rarely cause NSTEMI. Recognizing these uncommon embolic sources is vital for accurate diagnosis and management. Case Presentation: An 82-year-old female with severe aortic stenosis previously treated by transcatheter aortic valve replacement (TAVR), paroxysmal atrial fibrillation with a Watchman device, hypertension, diabetes, and heart failure with preserved ejection fraction presented with persistent chest discomfort and palpitations. Coronary angiography revealed a thrombus extending from the distal left main artery into the ostial left circumflex artery, successfully treated via aspiration thrombectomy and balloon angioplasty [Figure 1]. Transesophageal echocardiography (TEE) did not detect atrial thrombi. However, cardiac computed tomography (CT) identified thrombi on the prosthetic aortic valve leaflets, confirming the valve as the embolic source [Figure 2]. Discussion: This case emphasizes that NSTEMI may result from embolic thrombus, not solely from plaque rupture. Prosthetic valves, such as those used in TAVR, are rare but recognized sources of coronary embolism. Although TEE is frequently used, it has limitations in thrombus detection; thus, cardiac CT remains the preferred imaging modality for accurate evaluation. While coumadin is traditionally recommended for anticoagulation, Direct oral anticoagulants (DOACs) are emerging alternatives, though further studies are required to establish their efficacy. Conclusion: Clinicians should consider prosthetic valve-associated thromboembolism in NSTEMI cases post-TAVR. Cardiac CT is the optimal diagnostic tool, and future research should clarify the role of NOACs in managing prosthetic valve thrombosis.