Snapshot A 17-year-old boy is rushed to the emergency room after collapsing on the basketball court during a game. He is found to have a ventricular arrhythmia on electrocardiogram and died en route to the hospital. Prior to this event, he had a few episodes of syncope. His family history includes sudden cardiac death in 2 maternal uncles. Autopsy reveals markedly hypertrophic interventricular septum. Summary Hypertrophic Cardiomyopathy (HCM) is a prominent form of cardiomyopathy characterized by the thickening (hypertrophy) of the heart muscle, particularly the left ventricle. This condition is caused by genetic mutations affecting proteins that play a role in myocardial growth and contraction. HCM often presents in adolescents, young adults, and adults with diverse symptoms like chest pain, dyspnea, palpitations, and syncope. Diagnosis involves a comprehensive evaluation of clinical history, physical examination, electrocardiography (ECG), and echocardiography. Echocardiography is especially valuable for visualizing the hypertrophied heart muscle and assessing blood flow patterns. Treatment approaches for HCM aim to manage symptoms and reduce the risk of sudden cardiac death. Medications such as beta-blockers and calcium channel blockers are used. In severe cases, implantable cardioverter-defibrillators (ICDs) may be recommended. Surgical options like septal myectomy or alcohol septal ablation might be considered to relieve left ventricular outflow tract obstruction. Close monitoring and individualized treatment plans are crucial for optimal management of HCM patients. Epidemiology Incidence login to view 4 more bullets Demographics login to view 1 more bullet Location login to view 2 more bullets Risk factors login to view 2 more bullets Etiology Pathogenesis login to view 9 more bullets Genetics login to view 7 more bullets Associated conditions login to view 2 more bullets Anatomy Cardiac walls are thickened and myocytes are stacked Presentation Symptoms login to view 5 more bullets Physical exam login to view 6 more bullets Imaging Radiography login to view 6 more bullets Transthoracic echocardiography (TTE) login to view 6 more bullets Exercise echocardiography login to view 5 more bullets Cardiac MRI login to view 6 more bullets Studies Electrocardiogram login to view 5 more bullets Labs login to view 10 more bullets Histology login to view 1 more bullet Diagnosis Based on clinical presentation and echocardiogram Differential Restrictive cardiomyopathy login to view 3 more bullets Dilated cardiomyopathy login to view 3 more bullets Treatment Goals login to view 3 more bullets Medical login to view 12 more bullets Operative login to view 6 more bullets Techniques surgical septal myectomy login to view 11 more bullets implantable cardioverter defibrillator (ICD) login to view 16 more bullets Complications Sudden cardiac death from ventricular arrhythmias Heart failure Prognosis Many have normal life expectancy However, there is a risk of sudden cardiac death in the young athletic population