Abstract 2853: The Prevalence of Ion Channel Disorders in Victims of Sudden Adult Death Syndrome
Objectives: Sudden adult death syndrome (SADS) accounts for at least 4% of all sudden cardiac deaths in the United Kingdom and is often attributed to an ion channel disorder. The precise prevalence of and hence efficacy of effectiveness for screening for ion channel disorders utilising non-invasive cardiac tests in first degree relatives of victims of SADS is unknown. The aim of this study was to identify the prevalence of ion channel disorders in victims of SADS.
Methods: Between March 2006 and March 2007, 17 families of victims of SADS were evaluated in a tertiary inherited cardiac clinic. A total of 46 individuals underwent 12-lead ECG, echocardiography, exercise stress testing, 24 hour Holter and, when applicable, an Ajmaline provocation test and/or cardiac magnetic resonance scan.
Results: All family members had a structurally normal heart. An ion channel disorder was identified in 7 out of 17 (41%) families. Of these, 5 (71%) families exhibited the Brugada phenotype and 2 families manifested the long QT syndrome phenotype. A total of 11 of 46 (24%) asymptomatic family members were identified with an ion channel disorder.
Conclusions: Non-invasive cardiac evaluation of first-degree family members of victims of SADS in a tertiary inherited cardiac diseases clinic suggests that ion channel disorders, particularly Brugada’s syndrome, account for at least 40% of all SADS deaths in the UK.