Abstract
BACKGROUND: Despite increasing recognition of infiltrative cardiomyopathies, the heterogeneous group of diseases remains difficult to diagnose. CASE SUMMARY: We present an 82-year-old man with septal basal thickening initially thought to be hypertrophic cardiomyopathy. Further imaging was suspicious for sarcoidosis, but after several years without clinical improvement and the interval development of concentric hypertrophy, he was diagnosed with cardiac amyloidosis. DISCUSSION: Advanced imaging modalities are frequently used to evaluate suspected infiltrative cardiomyopathies. However, the effectiveness of imaging can be limited by the variable presentations of both sarcoid and amyloid. In this case, cardiac amyloidosis initially appeared on imaging with features characteristic of cardiac sarcoidosis on both positron emission tomography and cardiac magnetic resonance. Despite advancements in imaging technology, diagnostic limitations persist, potentially leading to misdiagnosis and delayed treatment. TAKE-HOME MESSAGES: Despite increasing recognition, cardiac amyloid and cardiac sarcoid are difficult to diagnose and require a high degree of clinical suspicion. Multimodality imaging can help discriminate between cardiomyopathies. However, limitations with current imaging modalities may lead to further diagnostic uncertainty.