EKG abnormalities during partial seizures in refractory epilepsy

Purpose: This study assessed the frequency and character of ictal cardiac r hythm and conduction abnormalities in intractable epilepsy. Sudden unexpect ed death in epilepsy (SUDEP) is a major cause of excess mortality in people with refractory epilepsy, and cardiac arrhythmias during seizures may be r esponsible. The frequency of cardiac abnormalities during seizures in patie nts with refractory epilepsy must be determined. Methods: Fifty-one seizures in 43 patients with intractable partial epileps y were analyzed prospectively from CCTV-EEG monitoring with one ECG channel . Arrhythmias, repolarization abnormalities, and PR and QT, intervals were determined for preictal (3 min), ictal, and postictal (3 min) periods for o ne or more seizures per patient. Parametric statistics were used for contin uous variables, and nonparametric statistics were used for categoric variab les. Results: Of the patients, 39% had one or more abnormalities of rhythm and/o r repolarization during or immediately after seizures. Abnormalities includ ed asystole (one), atrial fibrillation (one), marked or moderate sinus arrh ythmia (six), supraventricular tachycardia (one), atrial premature depolari zations (APDs; eight), ventricular premature depolarizations (VPDs; two), a nd bundle-branch block (three). Mean seizure duration was longer in patient s with abnormalities than in those without (204 vs. 71 s; p < 0.001). Gener alized tonic-clonic seizures were also associated with increased occurrence of ictal ECG abnormalities (p = 0.006) as compared with complex partial se izures. There were no clinically significant differences in mean preictal a nd ictal/postictal PR and QT, intervals. Conclusions: Cardiac rhythm and conduction abnormalities are common during seizures, particularly if they are prolonged or generalized, in intractable epilepsy. These abnormalities may contribute to SUDEP.