Lay summary
Sudden unexplained death in the young is a devastating occurrence with cardiac inherited diseases playing a significant causative role. We will explore the presentation and management of patients with cardiac inherited diseases (long QT syndrome, hypertrophic and dilated cardiomyopathy, Brugada syndrome, arrhythmogenic right ventricular dysplasia and catecholaminergic polymorphic ventricular tachycardia) over a 20-year period in New Zealand using the Cardiac Inherited Diseases Registry New Zealand. Developed in 2002, the "national, ethically approved consent-based registry" is part of the world's first national molecular genetic autopsy service and contains comprehensive clinical and genetic data of patients with inherited cardiac disease. It is hypothesised that following the introduction of family screening, locally (2002) and nationally (2009), presentations of cardiac arrest or sudden death will have decreased, as more pre-symptomatic patients are identified and commenced on protective therapies, supporting further investment in this strategy. Differences will be explored by ethnicity to ensure health equity.