Impaired Ventricular Repolarization Dynamics in Patients with Early Repolarization Syndrome
Article first published online: 1 FEB 2013
© 2012 Wiley Periodicals, Inc.
Journal of Cardiovascular Electrophysiology
Volume 24, Issue 5, pages 556–561, May 2013
How to Cite
TALIB, A. K., SATO, N., ASANOME, A., MYOJO, T., NISHIURA, T., YAMAKI, M., NAKAGAWA, N., SAKAMOTO, N., OTA, H., TANABE, Y., TAKEUCHI, T., KAWAMURA, Y. and HASEBE, N. (2013), Impaired Ventricular Repolarization Dynamics in Patients with Early Repolarization Syndrome. Journal of Cardiovascular Electrophysiology, 24: 556–561. doi: 10.1111/jce.12074
- Issue published online: 26 APR 2013
- Article first published online: 1 FEB 2013
- Accepted manuscript online: 17 DEC 2012 10:20AM EST
- Manuscript Accepted: 6 DEC 2012
- Manuscript Revised: 29 NOV 2012
- Manuscript Received: 17 OCT 2012
- early repolarization syndrome;
- J-wave syndrome;
- QT dynamics;
- QT interval;
- sudden cardiac death;
- T peak-T end;
- ventricular fibrillation
QT Dynamics in Early Repolarization Syndrome
Almost all current investigations on early repolarization syndrome (ERS) have focused on the J-wave characteristics and ST-segment configuration; however, few have reported on ventricular repolarization indexes in ERS.
Methods and Results
A total of 145 subjects were enrolled: 10 ERS patients, 45 uneventful ER pattern (ERP) subjects, and 90 healthy controls without J waves or ST-segment elevation. Ambulatory ECG-derived parameters (QT, QTc(B), QTc(F), T peak-Tend(Tpe), and QT/RR slope) were measured and statistically compared. Among the groups, there was no significant difference in the average QT and QTc(B); however, ERS patients had the shortest QTc(F) and longest Tpe (QTc(F): 396.2 ± 19 vs 410.4 ± 20 vs 419.2 ± 19 milliseconds, P = 0.036, Tpe: 84.9 ± 12 vs 70.4 ± 11 vs 66.9 ± 15 milliseconds, P < 0.001, for the ERS, ERP, and control groups, respectively). Importantly, the 24-hour QT/RR slope was significantly smaller in the ERS than ERP and control groups (QT/RR: 0.105 ± 0.01 vs 0.154 ± 0.02 vs 0.161 ± 0.03, respectively; P < 0.001). When analyzing the diurnal and nocturnal QT/RR slopes, ERS patients had small diurnal and nocturnal QT/RR slopes while the ERP and control groups had large diurnal and small nocturnal QT/RR slopes (diurnal QT/RR: 0. 077 ± 0.01 vs 0.132 ± 0.03 vs 0.143 ± 0.03, P < 0.001; nocturnal QT/RR: 0.093 ± 0.02 vs 0.129 ± 0.03 vs 0.130 ± 0.04, P = 0.02 in the ERS, ERP, and control groups, respectively).
ERS patients had a continuously depressed diurnal and nocturnal adaptation of the QT interval to the heart rate. Such abnormal repolarization dynamics might provide a substrate for reentry and be an important element for developing ventricular fibrillation in the ERS cohort.