Sudden cardiac death in the young. What's the rationale behind the irrationality in their surviving relatives?

摘要

Sudden cardiac death (SCD) at a young age (<40 years) is often the result of an underlying genetic heart disease, including inherited cardiomyopathies and primary electrical diseases. Especially in the latter category post-mortem examination fails to identify a cause of death because of the absence of structural abnormalities. The autosomal dominant inheritance pattern of most genetic heart diseases implies that first-degree relatives of a SCD victim have a 50% inheritance risk and are therefore also at increased risk of SCD. Because of this increased risk, which can also become manifest at older age due to reduced disease penetrance, periodic lifetime cardiac screening is advised for first-degree relatives. For most genetic heart diseases SCD prevention is possible by means of medication and/or an internal cardioverter defi-brillator.1 The identification of a genetic cause (DNA mutation) in the SCD victim offers the opportunity of predictive genetic testing in relatives (cascade screening). Relatives who do not carry the genetic predisposition are not at risk of disease and associated SCD and can be excluded from cardiac screening.