Yamaguchi Syndrome: A Rare Cardiomyopathy Mimicking Ischemic and Obstructive Patterns

Yamaguchi syndrome, a rare variant of apical hypertrophic cardiomyopathy, often mimics other cardiac conditions such as hypertrophic obstructive cardiomyopathy (HOCM) or ischemic heart disease due to overlapping clinical presentations. This report details the case of a 42-year-old male presenting with intermittent, nonexertional chest pain, initially suspected to have HOCM based on echocardiographic findings. Further evaluation, including cardiac magnetic resonance imaging and catheterization, revealed apical hypertrophy with a characteristic “spade-like” configuration of the left ventricle and absence of left ventricular outflow tract obstruction, confirming the diagnosis of Yamaguchi syndrome. The patient was managed conservatively with beta-blocker therapy and discharged with symptom improvement. This case highlights the diagnostic challenges of differentiating Yamaguchi syndrome from other cardiomyopathies and emphasizes the role of advanced imaging in guiding management.