Heart muscle cells contract because of the movement of certain molecules (called “ions”) across the walls (called “membranes”) of the cells. Channelopathies increase a child’s risk for life-threatening heart rhythms and sudden cardiac death (SCD). It is important to remember that while channelopathies are serious medical conditions, they are frequently treatable when they are detected and properly diagnosed.
Cardiac genetic testing and genetic counseling can be valuable tools when evaluating patients, and their family members, for channelopathies. The genetic changes that cause some channelopathies may even guide therapy suggested by your cardiologist or electrophysiologist (a cardiologist who specializes in heart rhythm conditions). If a known disease-causing genetic mutation (a change in the gene’s sequence or pattern) is found in a patient, it can help direct future testing in other family members to determine their risk of developing the disease.
Genetic testing can reveal the following results:
- Positive: This means a genetic mutation was identified that likely explains your child’s symptoms or cardiac testing results. Additional family members are usually tested for the positive gene to see if they are also carriers.
- Negative: This means that there was no identifiable gene that explains your child’s symptoms or test results. Not all genes have been identified and your child may still need treatment and follow up even if genetic testing is negative.
- Variant of unknown significance (VUS): A genetic variation was noted during genetic testing, but more research is needed to confirm its significance. As more data is collected, variants of unknown significance can be reclassified as positive or negative.
Genetic testing has become more affordable over the years, but can still be costly. It’s important to know your healthcare benefits and discuss testing options with your physician.
Most patients receive genetic testing results in a few weeks, but some tests may take longer to come back.
The decision about whether or not to do cardiac genetic testing is best made after a thoughtful discussion with your healthcare team.
For more information about living with the following conditions, visit SADS.org.