Coexistence of Inherited Cardiac Arrhythmia in Epilepsy as Neuro-cardiac Channelopathy: From Hypothesis to Evidence

Sudden unexpected death in epilepsy (SUDEP) accounts for 5-30% of deaths in patients with epilepsy. Past research has attempted to reveal these mechanisms, but the specific risk factors and pathophysiology have not been established. Inherited lethal cardiac arrhythmias can be erroneously diagnosed as epilepsy. A diagnosis of coexistent epilepsy cannot be completely excluded in the inherited cardiac arrhythmias but the differential diagnosis is often challenged. SUDEP may be attributed to seizure-induced fatal cardiac arrhythmias or cardiopulmonary dysfunction as a secondary cause. The expanding knowledge base has increased the understanding of the structure-function and genotype-phenotype relationships of ion channels and has provided insights into the pathophysiological basis of common diseases such as cardiac arrhythmias and epilepsy. In this review, the mechanisms for SUDEP and the possible relationships between epilepsy and inherited cardiac arrhythmias as “neuro-cardiac channelopathy” have been discussed based on clinical and genetic evidence.