Electrocardiographic Markers of Sudden Unexpected Death Risk in Pediatric Epilepsy: A Comparative Study of Generalized and Focal Seizures.

: Sudden unexpected death in epilepsy (SUDEP) is a major cause of mortality in pediatric epilepsy. Cardiac arrhythmias, possibly reflected by electrocardiographic (ECG) abnormalities, are thought to contribute significantly to SUDEP risk. This study aimed to evaluate ECG indices associated with an increased risk of both atrial and ventricular arrhythmias and sudden cardiac death in pediatric patients with generalized and focal seizures, excluding those with underlying channelopathies. : Pediatric patients aged 0-18 years with generalized or focal epilepsy followed at our center between October 2024 and April 2025 were enrolled. Comprehensive cardiac evaluations, including echocardiography and 12-lead ECG, were conducted. Patients with channelopathies, structural heart defects, or significant congenital heart disease were excluded. ECG parameters-QT dispersion (QT Disp), corrected QT interval (QTc), QTc dispersion (QTc Disp), P-wave dispersion (P Disp), and T peak-T end interval (Tp-e)-were analyzed across epilepsy subgroups and compared to healthy controls. Effects of antiepileptic drug (AED) use and gender were also assessed. : A total of 151 participants were included (generalized: = 51; focal: = 50; controls: = 50). QTc and Tp-e intervals were prolonged in both epilepsy groups compared to controls ( = 0.001 and = 0.036, respectively), however, they fell within the conventional parameters. AED use was associated with further prolongation of QTc ( = 0.035) and Tp-e ( = 0.037), these metrics were similarly found to be within the established normative boundaries. Phenobarbital and lamotrigine users showed the longest QTc, albeit not statistically significant. Males with generalized seizures had longer maximum P-wave duration (P Max) than females ( = 0.009). A moderate correlation was found between Tp-e and QTc (r = 0.557, = 0.001). : Although there are findings in our study that may suggest a relationship between SUDEP and arrhythmia according to electrocardiographic markers associated with arrhythmia risk, larger and prospective studies with long-term follow-up are needed in the future.