A form of cardiac muscle disease, characterized by left and/or right ventricular hypertrophy (hypertrophy, left ventricular; hypertrophy, right ventricular), frequent asymmetrical involvement of the heart septum, and normal or reduced left ventricular volume. Risk factors include hypertension; aortic stenosis; and gene mutation; (familial hypertrophic cardiomyopathy). [MeSH]