EEG and ECG in sudden unexplained death in epilepsy
Nei M, Ho RT, Abou-Khalil BW, Drislane FW, Liporace J, Romeo A, and Sperling MR (2004) EEG and ECG in sudden unexplained death in epilepsy. Epilepsia 45:4 338–45.
Abstract: PURPOSE: Sudden unexpected death in epilepsy (SUDEP) is a major cause of mortality for patients with epilepsy. Cardiac factors may be involved and were evaluated in this study. METHODS: EEG and ECG data for 21 patients with definite (n = 6) or probable (n = 15) SUDEP were compared with data from a group of 43 patients with refractory partial epilepsy. ECG abnormalities and heart rate (HR) changes were correlated with clinical data. RESULTS: Fourteen patients died in their sleep; two were awake. Ictal maximal HR (90 seizures from 16 of 21 patients) was significantly higher in SUDEP (mean, 149 beats/min, BPM) than in comparison patients (mean, 126 BPM; p < 0.001). Greater increases in HR were associated with seizures arising from sleep (78 BPM increase) than from wakefulness (47 BPM; p < 0.001) in SUDEP, as compared with the non-SUDEP group (52 BPM in sleep, 43 BPM in wakefulness; p = 0.27). Ictal cardiac repolarization and rhythm abnormalities occurred in 56% of SUDEP (including two atrial fibrillation, two ventricular premature depolarizations, two marked sinus arrhythmia, two atrial premature depolarizations, one junctional escape, one ST-segment elevation), and 39% of comparison patients (p = 0.39). No specific seizure onset (laterality or lobe) was associated with SUDEP. CONCLUSIONS: This study reveals, for the first time, evidence of increased autonomic stimulation (as measured by HR) associated with seizures, particularly in sleep, in patients with SUDEP, as compared with a clinically similar group of patients with refractory epilepsy.
Keywords: SUDEP, ECG, EEG
Context
- Retrospective study of EEG and EKG recordings from patients whose deaths were classed as definite or probable SUDEP, as compared with recordings from control group of living patients with refractory partial seizures. Ictal HR was higher in SUDEP. SUDEP patients but not control patients had significantly higher HR for seizures beginning while sleeping than those occurring while awake. This could contribute to the frequency of SUDEP deaths overnight and in the morning. There was a trend for greater frequency of cardiac dysfunction during seizure in the SUDEP group. Interestingly, both preictal and ictal heart rates increased over each of five seizures that occurred in a cluster in one patient and in 3 seizures in a slightly more temporally spread cluster in another patient.