SADS is an umbrella term to describe unexpected deaths in young people (usually 40 years of age), whose cause of death following post mortem examination is ‘undetermined’ or ‘unascertained’.3
The most common SADS conditions include genetic arrhythmia syndromes such as long QT syndrome, catecholaminergic polymorphic ventricular tachycardia (CPVT) and Brugada syndrome.
These conditions follow an autosomal dominant inheritance pattern. Therefore, first-degree relatives (ie parents, siblings, children) of an individual who has a genetic arrhythmogenic disorder are at a 50% risk of also having a gene variant for the condition, and thus, at risk of developing the condition. All these conditions show considerable clinical variability within families and have incomplete penetrance.1,4,5
Of interest are individuals presenting with:3
- any first-degree relatives with unexplained sudden cardiac death <40 years of age
- episodes of unexplained syncope
- syncope or seizures during exercise, excitement or startle.
Collect a comprehensive family history (three generations), noting any relatives with the features above.3