Abstract
Antiphospholipid syndrome (APS) is known for thrombotic events and pregnancy complications, but its association with myocarditis is rare and poorly understood. A 44-year-old woman presented with acute chest tightness, elevated cardiac biomarkers, and severe anemia. Diagnostic workup revealed ST-segment changes on electrocardiogram, preserved left ventricular function on echocardiography, and myocardial inflammation on cardiac magnetic resonance imaging, suggestive of acute myocarditis. Positive antiphospholipid antibodies confirmed APS. She was managed with close multidisciplinary follow-up. APS-associated myocarditis poses diagnostic challenges because of its atypical presentation and overlap with other cardiac conditions. This case highlights the role of cardiac magnetic resonance imaging in diagnosing myocarditis early, guiding management strategies, and the need for heightened clinical suspicion in APS patients presenting with cardiac symptoms.