Familial Dilated Cardiomyopathy (DCM)

Dilated cardiomyopathy (or DCM) is a type of cardiomyopathy. The lower pumping chambers of the heart — the ventricles — are dilated, too stretched out. By being abnormally large, the ventricles can’t properly contract, making the heart unable to effectively pump blood throughout the body. The disease can spread to the heart’s atria, the upper pumping chambers.

Familial dilated cardiomyopathy means a genetic form of DCM occurs in multiple members of a family. Siblings, parents, aunts and uncles, or grandparents may be affected. Nearly a third of people who have the condition inherited it.

Dilated cardiomyopathy (DCM) doesn’t always create symptoms, but when they surface, they can include:

• Abdominal pain
• Chest pain
• Chronic fatigue
• Frequent vomiting
• Pale or clammy skin
• Rapid breathing
• Rapid heartbeat
• Shortness of breath
• Slow or delayed growth

While dilated cardiomyopathy can have different causes, familial DCM is caused by a genetic change in an individual’s DNA or genetic material. (The change is also known as a genetic variant or mutation.) While there are thousands of genes in our DNA, only a small group of them are associated with familial DCM. Having a genetic change can increase the risk to develop DCM, but not all individuals who carry a DCM genetic change will develop the condition. Additionally, some children and their family members with familial DCM will have normal genetic test results. This does not rule out a genetic cause for the condition; it simply means that the genetic cause could not be identified.

Some forms of familial DCM are syndromic. This means that in addition to DCM, a child and their family members may have additional symptoms that affect organs or body parts outside of the heart. But many forms of DCM are non-syndromic; DCM is the only feature.

Familial DCM, just like the other types of DCM, is diagnosed through a cardiac evaluation with a cardiologist. If DCM is suspected or there is a concern based on family history, your doctor may recommend specific tests to see the structure of your and your child’s heart and assess its ability to function. Tests may include:

• Blood tests
• Chest X-rays
• Electrocardiogram (EKG or ECG)
• Echocardiogram (cardiac ultrasound)
• Cardiac magnetic resonance imaging (MRI)
• Stress echocardiography, which uses ultrasound and heart rate monitoring to assess your child’s heart function just before and just after exercise
• Exercise stress test
• Cardiac catheterization
• Coronary angiography

Genetic testing can also help reach a diagnosis. Genetic testing is performed through a simple blood or cheek swab test. If your health care provider recommends genetic testing, the team will arrange genetic counseling to walk your family through the process of testing, determine the most appropriate test, and discuss the advantages and limitations of testing. The team at Boston Children’s Center for Cardiovascular Genetics includes clinicians with experience in the diagnosis and treatment of DCM as well as genetic counselors who are familiar with ordering genetic testing for DCM.

Treatment options will be determined by the specific symptoms being exhibited. If you or your child has no symptoms, you might not immediately need medication or other treatment. Instead, the cardiologist will monitor you or your child to gauge the progression of the disease.

Individuals with more serious symptoms may need additional tests to give the treatment team more detailed information about how the cardiomyopathy is affecting the heart and the rest of the body. Many people with cardiomyopathy do well with medication alone. Others need surgery, and in the most severe cases some people need a heart transplant.

At the Center for Cardiovascular Genetics, we strive to provide comprehensive care and support to individuals and family members who have DCM. Before your visit, we will collect all relevant information related to you and your family. This could include prior tests or evaluations you, your child, or your family may have had.

At your visit, you or your child may see many members of our multidisciplinary team, including cardiologists, a geneticist, nurse practitioners, genetic counselors, and a cardiovascular psychologist. During your visit, we will discuss your results and make a plan for your care management. Based on results, we may recommend further tests or monitoring. Our patients are seen on a regular basis to monitor changes in symptoms.

Understanding how a condition behaves within a family is very important to understand you and your family members’ risks. It is a priority for us to help you understand your condition and provide comprehensive information on key aspects of your condition, such as prognosis, treatment plans, and family planning. To help with interpretation and coordination, we often see multiple members of a family on the same day.

We are happy to help you through the process.