MYH7 hypertrophic cardiomyopathy with heart block presenting with A case

Background: Hypertrophic cardiomyopathy is characterized by cardiac myocyte hypertrophy leading to ventricular hypertrophy and can lead to heart failure and sudden cardiac death in pediatric patients. Aim of review: To present a case of hypertrophic cardiomyopathy initially presenting with papilledema and visual symptoms, highlighting the importance of early recognition and genetic screening. Key scientific concepts of review: A 4-year-old boy presented with visual symptoms and papilledema. Initial evaluation revealed sinus bradycardia, left bundle branch block, left ventricular hypertrophy with abnormal repolarization, and biatrial enlargement on electrocardiogram. Echocardiography demonstrated severe interventricular septal hypertrophy (thickness, 1.5 cm; z score, +5.2) consistent with obstructive hypertrophic cardiomyopathy. The patient developed syncope with documented atrioventricular block Mobitz type II and progressive ventricular tachycardia, ultimately requiring heart transplantation. Genetic testing identified a pathogenic MYH7 (beta-myosin heavy chain) gene mutation. This case emphasizes that hypertrophic cardiomyopathy may present with seemingly unrelated symptoms and underscores the importance of family genetic screening, prenatal counseling, and testing.