Sudden cardiac death and cardiac sodium channel diseases

Sudden cardiac death (SCD), accounting for a substantial part of the forensic autopsy, is a leading cause of mortality worldwide. Lethal arrhythmia due to sodium channel diseases is recognized as one of the most prevalent etiologies of SCD. In these disorders, defective cardiomyocytes, including the pacemaker and the working cardiomyocytes, would manifest as abnormal electrical activity and morphology, thereby predisposing individuals to SCD. It is always a problem for forensic pathologists to adjudicate a sudden death caused by sodium channel diseases since structural changes in those cases are often inconspicuous. With the advent of the molecular autopsy, forensic pathologists can conduct targeted gene testing to identify the risk of SCD for family members of the probands. This review aims to discuss the relationship between SCD and sodium channel diseases, clarify the underlying mechanisms, and provide prophylactic suggestions for the relatives of SCD patients at risk.