Genetic Heart Testing for Families Affected by Sudden Cardiac Death

Sudden cardiac death means a person dies unexpectedly because the heart stops working effectively. There are many possible causes. Some are linked to the heart's structure or muscle, and some are linked to the heart's electrical system. In some families, an inherited condition may play a role.

Genetic heart testing looks at a person's DNA for changes, called variants, in genes connected with inherited heart rhythm conditions and inherited cardiomyopathies (diseases of the heart muscle). A test can show risk or carrier status. It does not diagnose heart disease on its own.

Results only make sense alongside personal and family history, a physical exam, imaging and bloodwork, reviewed by a qualified cardiologist, electrophysiologist or genetic counselor. A negative result does not rule out risk. A variant of uncertain significance is not a diagnosis. It means experts do not yet know what that change means.

Families have traditionally started by gathering medical history. That often includes what is known about the person who died, any available records, and whether other relatives have had fainting spells, seizures without a clear cause, heart rhythm problems, or early heart disease.

Clinicians have also traditionally used non-genetic evaluations for relatives, such as a physical exam, an electrocardiogram, heart imaging and other heart-rhythm monitoring. Which of these are appropriate is decided by a licensed clinician for each person.

Genetic testing is sometimes part of this picture. When a disease-causing variant is found in one person, cascade testing, which means offering testing to biological relatives, has traditionally been discussed. Genetic counseling is generally recommended before and after testing. Counselor licensing varies by state.

A cardiologist or cardiac electrophysiologist, a doctor who specializes in the heart's electrical system, who works with inherited conditions may help you make sense of your family's story. A first visit often involves reviewing family and personal history, a physical exam, and a conversation about which evaluations may or may not be useful. Nothing is promised, and recommendations depend on each person.

If genetic testing comes up, the right provider may explain what the test can and cannot tell you, who in the family might be tested first, and how results would be interpreted. They may also work with a genetic counselor to help you consider the emotional and practical sides of knowing.

Questions you might bring: Is genetic testing appropriate for me or for my family? Who should be tested first? What would a negative or uncertain result mean? How would results affect my relatives? What does my insurer cover? How does GINA apply, and what about life, disability or long-term-care insurance? Which records, such as autopsy or prior test results, should I gather?