Late Anthracycline Cardiotoxicity Mimicking Arrhythmogenic Cardiomyopathy in a Young Adult.

BACKGROUND: Doxorubicin-induced cardiotoxicity can manifest years after exposure and may mimic other cardiomyopathies in young patients, making the diagnosis of delayed doxorubicin cardiotoxicity challenging in these patients. CASE SUMMARY: A 26-year-old physically active man with childhood Burkitt's lymphoma treated with doxorubicin (120 mg/m2 cumulative) presented with exertional chest discomfort and palpitations. Resting electrocardiogram and ambulatory monitoring were unremarkable. Transthoracic echocardiography demonstrated preserved ejection fraction (55%-60%) but reduced global longitudinal strain (-15%). Cardiac magnetic resonance revealed low-normal biventricular function with nonischemic septal late gadolinium enhancement and reduced strain. Exercise stress testing demonstrated impaired contractile reserve, septal mechanical dyssynchrony, and exercise-induced QRS prolongation. Coronary computed tomography angiography excluded coronary artery disease. DISCUSSION: This case highlights that anthracycline cardiotoxicity may present late, mimic myocardial ischemia, arrhythmogenic cardiomyopathy, and other cardiomyopathies. TAKE-HOME MESSAGE: A high index of suspicion is required for late cardiotoxicity in young cancer survivors.