Abstract
BACKGROUND: Hypertrophic cardiomyopathy (HCM) and infiltrative cardiomyopathies are important causes of cardiogenic syncope with overlapping clinical and radiologic features. CASE SUMMARY: A 49-year-old gentleman presented with syncope while walking across the Brooklyn Bridge. Electrocardiogram revealed low-voltage QRS with diffuse T-wave inversions. Echocardiography revealed moderate left ventricular hypertrophy, wall motion abnormalities with left ventricular ejection fraction 35% to 40%, and a dilated, hypokinetic right ventricle. Cardiac magnetic resonance showed biventricular hypertrophy and evidence of late gadolinium enhancement. Positron emission tomography/magnetic resonance (PET/MR) 18F-FDG revealed right ventricle uptake along with matching late gadolinium enhancement and FDG avidity in the hilar and mediastinal lymph nodes. Endomyocardial biopsy showed noncaseating granulomas, confirming sarcoidosis. An implantable cardioverter-defibrillator was inserted. Despite immunosuppression and guideline-directed medical treatment, the patient eventually required cardiac transplantation. DISCUSSION: Cardiac sarcoidosis mimicking genetic cardiomyopathy, and vice versa, has often been reported. Combined PET/MR helped distinguish these pathologies in our patient. TAKE-HOME MESSAGES: Cardiac sarcoidosis can mimic HCM; multimodal imaging, including PET/MR, guided by clinical suspicion, is important. Biventricular involvement in HCM is infrequent.