What causes hypertrophic cardiomyopathy?

Hypertrophic cardiomyopathy (HCM) usually is inherited. It’s caused by a mutation (change) in some of the genes in heart
muscle proteins. HCM also can develop over time because of high blood pressure or aging. Other diseases, such as diabetes or
thyroid disease, also can cause HCM. Sometimes the cause of the disease isn’t known.