Does cardiac conduction pathology contribute to sudden unexpected death in epilepsy?

Heart weights have been reported to be increased in those dying suddenly and unexpectedly from epilepsy (SUDEP) and it has been suggested that cardiac pathology including cardiac conduction pathology and coronary artery atheroma may contribute to SUDEP. The purpose of this study was to perform a detailed controlled study of the microscopic pathology of the cardiac conduction system in SUDEP cases, in addition to assessing coronary artery atheroma and other cardiac pathology. The hearts of ten SUDEPs and ten control subjects (no history of epilepsy and a cause of death not primarily cardiac) were examined macroscopically and microscopically by two pathologists blinded to the patient group. Morphological abnormalities of the cardiac conduction system that could have possibly contributed to death were not increased in the SUDEP group (four cases showed such changes in the SUDEP group vs. six in the control). There was no significant difference between the maximal percentage coronary artery stenoses between the two groups and no increased prevalence of other cardiac pathology in the SUDEP group. However, since subtle abnormalities of the conduction system were identified in some of the epileptic deaths, it is still feasible that these may contribute to death by causing cardiac arrhythmia, when associated with apnoea, bradycardia or other cardiac arrhythmia related to an epileptic seizure.