Genetics can play a big role in your health and how your body functions. In general, if you have at least one male family member diagnosed with heart disease or who had a heart condition before age 55 (or one female family member before the age of 65), you may be at a higher risk of developing heart disease. The three most common inherited heart diseases are familial hypertrophic cardiomyopathy, which thickens part of the heart muscles, familial dilated cardiomyopathy, which thins the heart muscles, and familial hypercholesterolemia (FH), which causes very high cholesterol. Knowing your family history is critical in recognizing inherited conditions.