European Heart Journal Advance Access published online on October 29, 2009
European Heart Journal, doi:10.1093/eurheartj/ehp423
Mode of onset of ventricular fibrillation in patients with early repolarization pattern vs. Brugada syndrome
1 Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, 138-736, Poongnap-dong 388-1, Songpa-gu, Seoul, Republic of Korea
2 Health Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
3 Division of Cardiology, Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Hospital, Busan, Republic of Korea
4 Department of Internal Medicine, Sanggye Paik Hospital, College of Medicine, Inje University, Seoul, Republic of Korea
5 Division of Cardiology, Department of Internal Medicine, Chonbuk National University, Chonbuk, Republic of Korea
6 Masonic Medical Research Laboratory, 2150 Bleecker Street, Utica, NY 13501-1787, USA
Received 20 December 2008; revised 23 April 2009; accepted 11 June 2009 * Corresponding authors. Tel: +82 2 3010 3159, Fax: +82 2 486 5918, E-mail: gbnam{at}amc.seoul.kr (G.-B.N); Tel: +1 315 735 2217, Fax: +1 315 735 5648, E-mail: ca{at}mmrl.edu (C.A.)
Aims: The aim of the present study was to identify specific electrocardiogram (ECG) features that predict the development of multiple episodes of ventricular fibrillation (VF) in patients with an early repolarization (ER) pattern and to compare the mode of VF initiation with that observed in typical cases of Brugada syndrome (BrS).
Methods and results: The mode of the onset and the coupling intervals of the premature ventricular contractions (PVCs) initiating VF episodes were analysed in patients with BrS (n = 8) or ER who experienced sudden cardiac death/syncope or repeated appropriate implantable cardioverter defibrillator shocks. Among the 11 patients with ER, 5 presented with electrical storm (ES, four or more recurrent VF episodes/day). The five ES patients displayed a dramatic but very transient accentuation of J waves across the precordial and limb leads prior to the development of ES. Ventricular fibrillation episodes were more commonly initiated by PVCs with a short–long–short (SLS) sequence in ER (42/58, 72.4%) vs. BrS patients (13/86, 15.1%, P < 0.01). Coupling intervals were significantly shorter in the ER group compared with those with BrS [328 (320, 340) ms vs. 395 (350, 404) ms, P < 0.01].
Conclusion: Our study provides additional evidence in support of the hypothesis that ER pattern in the ECG is not always benign. Transient augmentation of global J waves may be indicative of a highly arrhythmogenic substrate heralding multiple episodes of VF in patients with ER pattern. Ventricular tachycardia/VF initiation is more commonly associated with an SLS sequence, and PVCs display a shorter coupling interval in patients with ER pattern compared with those with BrS.
Key Words: Sudden cardiac death • Ventricular fibrillation • Electrocardiography • J waves • Electrical storm