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). 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]. 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.
Background—: Early recurrence (ER) of atrial tachyarrhythmias during the first 3 months (blanking period) after atrial fibrillation ablation can be highly symptomatic, often requiring emergency treatment. Short-term steroid therapy may suppress ER during the blanking period. Methods and Results—: We prospectively enrolled 138 patients who were randomly assigned to 2 groups (steroid group and control group). An intravenous bolus of 0.5 mg/kg of methylprednisolone for 2 days followed by 12 mg daily of oral methylprednisolone for 4 days was given to the steroid group patients. The primary end point was ER during the blanking period (3 months post ablation). During the blanking period, 51 of the 138 (37.0%) patients experienced ER after atrial fibrillation ablation. The steroid group had a lower rate of ER than the control group (15/64 [23.4%] versus 36/74 [48.6%], P =0.003). There was no difference between the 2 groups about late recurrence during a 24-month follow-up (log-rank test, P =0.918). In a multivariate analysis, short-term steroid therapy was independently associated with a lower rate of ER during the blanking period (adjusted OR, 0.45; 95% confidence interval, 0.25–0.83; P =0.01). Conclusions—: Periprocedural short-term moderate intensity steroid therapy reduces ER (≈3 months) after catheter ablation of atrial fibrillation. It is not effective in preventing late (3≈24 m) atrial fibrillation recurrence. Clinical Trial Registration—: URL: www.who.int/ictrp ; Unique identifier: KCT0000107.