A heart muscle disease of uncertain cause, marked by excessive and disorganized growth of myofibrils, impaired filling of the heart (diastolic dysfunction), a reduction in the size of ventricular cavities, and often, ventricular arrhythmias and sudden death. Examination of the heart by echocardiography or other modalities may show the heart’s enlargement to be most pronounced in the interventricular septum. Hypertrophy in that location may limit the flow of blood (and increase pressure gradients) from the left ventricle to the aorta. Abnormal anterior motion of the mitral valve during systole also may be found. These two findings are often designated on echocardiographic reports of patients with HCM by the following abbreviation: ASH-SAM (“asymmetric septal hypertrophy-systolic anterior motion” of the mitral valve).
Hypertrophic cardiomyopathy is a condition that affects the heart muscle, causing the walls of the left ventricle, the lower chamber of the heart, to thicken abnormally. This thickening hampers the heart’s ability to pump effectively, potentially leading to symptoms such as breathlessness, chest pain, and heart palpitations.
Hypertrophic cardiomyopathy is primarily an inherited condition, demonstrating an autosomal dominant pattern of inheritance. Family members can be tested for the condition using echocardiography, although it may not become evident until after puberty. The condition is occasionally responsible for sudden death in young individuals.
Management of this condition often involves the use of antiarrhythmic medications, and in some instances, an implantable defibrillator may also be required.