What role do genetic tests play in the assessment of patients with a history of sudden cardiac death in their family?

Genetic testing plays a crucial role in the assessment of patients with a family history of sudden cardiac death (SCD), particularly in identifying inherited cardiovascular diseases and informing management strategies (Thomas and Battle, 2015; Laracuente et al., 2019). Following a sudden cardiac death in a family, genetic assessment is important to understand potential underlying causes (Laracuente et al., 2019). This assessment can also aid in evaluating the risk of SCD in pediatric primary electrical disorders (Pupaza et al., 2023).

Before offering genetic testing, comprehensive genetic counselling is essential, ideally involving two sessions ². This counselling should be conducted by a healthcare professional with appropriate training ². Discussions should cover the potential risks and benefits of genetic testing, the probability of finding a mutation, and the implications of the results for both the individual and their family ². Patients should also be informed about the likely informativeness of the test, including the meaning of positive, negative, or uncertain results, and the expected timescale for receiving results ².

For mutation finding, testing should ideally begin with an affected family member where possible ². If a pathogenic variant is identified, cascade testing should then be offered to first-degree relatives ¹. The selection of an appropriate gene panel for testing should be guided by the individual's family or personal history, utilising resources such as the UK national genomic test directory ¹. Genetic services should offer genetic counselling and testing to individuals who have a raised probability of having a pathogenic variant based on a verified family history ¹. If no clear genetic diagnosis is found, families should be informed that they can request a review in a specialist genetic clinic at a future date ². Clinical genetics laboratories are expected to record gene variants of uncertain significance and known pathogenic mutations in a searchable electronic database ².