In some forms of inherited heart diseases, genetic tests can be helpful when trying to identify which family members may be at risk of developing or carrying the condition.

Testing for a range of cardiac inherited conditions is available, including Long QT syndrome (LQTS) and Hypertrophic Cardiomyopathy (HCM).

Genetic testing involves a blood or saliva test, from which the lab extracts DNA. The lab looks at the genes linked to the condition suspected. The DNA from the first family member to be tested has to undergo a sequencing of the genes - in effect looking for spelling errors in a number of genes. The test is highly specialised and time consuming. In 2023 this can take up to 3 months.

Once a genetic variant has been identified, in one or more genes,  these can be looked for in the other family members. These tests can take between 6 weeks to 3 months. 

Each person having the test must be counselled carefully first, by a specialist or clinical geneticist or associate, and the patient must give their written informed consents.

GPs and patients themselves may not order such tests, however GPs can refer their patients and families to the service for evaluation if there is a strong family history of cardiac inherited disease or young sudden deaths that appear to run in the family.