Nora Eccles Harrison Cardiovascular Research & Training Institute

Is Cardiomyopathy Hereditary? Unraveling the Role of Familial/Inherited Heart Conditions

hands holding beeping heart

Is cardiomyopathy genetically inherited? Cardiomyopathy is a problem that makes it harder for your heart to pump blood as it should. This condition has many causes and can affect people of all ages. Depending on the type of cardiomyopathy a person has, the heart muscle may become thicker, larger, or stiffer than it should be.

These issues lead to weaker hearts, irregular heartbeat, heart failure, or even cardiac arrest. But is this something you inherit through your genes? This guide will help explain the role of your genes in familial hypertrophic cardiomyopathy.

Is There a Genetic Cause of Dilated and Hypertrophic Cardiomyopathy?

Cardiomyopathy can be inherited through genes or acquired through another condition. Depending on the type of cardiomyopathy a patient has, there may be a genetic mutation or variants to blame for the condition.

For example, familial hypertrophic cardiomyopathy has been linked to variants in the following genes:

  • MYH7
  • MYBPC3
  • TNNT2
  • TNNI3

In contrast, familial dilated cardiomyopathy has been linked to mutations in more than 30 different genes, with TTN accounting for about 20 percent of all cases. The genes affected by the mutations in both inherited cardiomyopathies provide instructions for making the proteins found in cardiac muscle cells. Mutations in the genes of a patient can lead to proteins not doing what they should.

How Does Genetics Play a Role in Heart Disease?

Your genes affect everything about you, from your appearance to your blood type. Genes have also shown the ability to play a role in your chances of developing heart disease. If you have a family history of heart disease, such as in your parents or siblings, you have an increased risk of developing the same disease.

For example, research has shown that 50 percent of a person’s risk of developing coronary artery disease (CAD) is determined at birth by their genetic makeup. Lifestyle factors determine the other 50 percent as the person ages. If there’s a family history of early-onset heart disease (especially when the people affected live healthy lives), it’s worth considering you may have a genetic disposition to heart disease.

Forms of Familial Hypertrophic Cardiomyopathy

Concerning familial hypertrophic cardiomyopathy, four forms of this condition have higher chances of being genetic. If you or an immediate family member have any of these conditions, it’s worth undergoing genetic testing to see if the issue is inherited:

  • Hypertrophic cardiomyopathy (thickening of the heart walls)
  • Dilated cardiomyopathy (enlargement and weakening of the heart)
  • Arrhythmogenic right ventricular cardiomyopathy (fatty tissue in the heart that causes irregular heart rhythms)
  • Restrictive cardiomyopathy (stiffened heart muscle)

What Is the Genetic Inheritance of Restrictive Cardiomyopathy (Cardiovascular Disease)?

Individuals with restrictive cardiomyopathy have stiff heart muscles that cannot fully relax after each contraction, causing blood back up in the atria and lungs while reducing the blood that makes it to the ventricles. In most cases of restrictive cardiomyopathy, genetic inheritance is to blame. A parent with the genetic mutation has a 50 percent chance of passing the same mutation on to their child.

Several genes have been connected to familial restrictive cardiomyopathy, with mutations in the TNNI3 gene being the most common cause. This gene provides instructions for making the cardiac troponin I protein, which is found in the heart and helps regulate the contraction and relaxation of the heart muscle.

Restrictive cardiomyopathy is inherited in an autosomal dominant pattern. This means that just one copy of the mutated gene in each cell is enough to cause the disorder. Restrictive cardiomyopathy is the least common type of cardiomyopathy, accounting for about five percent of all cases of familial hypertrophic cardiomyopathy.

However, many people can have the condition without showing any symptoms, so it’s vital to undergo genetic testing if anyone in your family has been diagnosed with this form of familial cardiomyopathy. Even without symptoms present, those with this inherited cardiovascular disease are at risk of severe complications such as heart failure and sudden cardiac arrest.

Final Thoughts

Lifestyle choices can cause cardiomyopathy, but many cases are also connected to a person’s genetic makeup. If your family has a history of cardiomyopathy, you must visit your doctor and undergo hereditary cardiomyopathy genetic testing to see if you have gene mutations that can cause the same condition. Many people can have familial hypertrophic cardiomyopathy and not realize it until severe complications arise, which is why the testing is so important, so you know when to seek immediate care and treatment.

If you are at risk for genetic cardiomyopathy, it’s crucial to do all you can to lead a healthy lifestyle to help prevent the onset of conditions. A healthy diet and regular cardiovascular exercise may sometimes help offset the risk factor. Early testing and diagnosis can be the key to living a healthy life with genetic cardiomyopathy.