Alteration of Corrected QT Interval Associated with Generalized Tonic-Clonic Seizures induced by Electroconvulsive Therapy (ECT)
Abstract number :
1.061
Submission category :
3. Neurophysiology
Year :
2015
Submission ID :
2326261
Source :
www.aesnet.org
Presentation date :
12/5/2015 12:00:00 AM
Published date :
Nov 13, 2015, 12:43 PM
Authors :
Y. Suzuki, M. Miyajima, K. Ohta, N. Yoshida, M. Okumura, M. Nakamura, T. Sasano, T. Kawara, M. Matsuura, E. Matsushima
Rationale: Electrocardiogram (ECG) abnormalities have been reported in 35% of seizures. A corrected QT interval (QTc) prolongation indicates delayed ventricular repolarization, which can trigger ventricular arrhythmias. Conversely, abnormal QTc shortening can facilitate re-entrant excitation leading to ventricular tachycardia and sudden cardiac death. Herein, we examined QTc changes in high time resolution during induced generalized tonic-clonic seizures in electroconvulsive therapy (ECT).Methods: Sixteen patients with depression who underwent ECT were recruited (thirteen women, 66.3±7.2 years old). A total of 125 ECT sessions were assessed using electrocardiograms. Heart rate (HR), QT interval, and QTc were analyzed using Bazett and Fridericia formula. We averaged QTc and defined 30s pre-stimulation as baseline, and then compared QTc between baseline and post stimulation.Results: There was a significant prolongation of Bazett and Fridericia QTc compared with baseline at 0–30s after stimulus onset. Bazett QTc significantly decreased compared with baseline at 80–130s after stimulus onset. Fridericia QTc significantly decreased compared with baseline at 30–80s after stimulus onset, and further decrease at 80–130s. HR increased significantly at 0–30s after stimulus onset.Conclusions: We observed an immediate increase in Fridericia QTc after ECT stimulus, followed by a continuous decrease thereafter. The increase in QTc observed following stimulation might be caused by imbalanced sympathetic discharge. These data suggest that the risk of torsade de pointes may be enhanced around seizures on EEG. And the gradual decrease in QTc may increase the risk of ventricular tachycardia after seizures on EEG. Generalized tonic-clonic seizure is a biomarker of sudden unexpected death in epilepsy (SUDEP), while seizure-related prolongation and shortening of QT interval have been shown in subjects with epilepsy who have died suddenly. Our findings may be related to the physiological mechanism of SUDEP as a model of induced generalized tonic-clonic seizure.
Neurophysiology