Introduction: Antiarrhythmic drugs are often administered after catheter ablation (CA) in patients with atrial fibrillation (AF); however, it is unclear for how long it should be continued. Methods: We administered hybrid therapy consisting of CA and bepridil to 130 patients with persistent AF and left atrial (LA) enlargement (volume index >48 ml/m 2). After a 2-month of hybrid therapy, bepridil discontinuation was attempted. All patients underwent echocardiography 6 months after CA. We investigated the relationship between the duration of bepridil administration and the recurrence of AF after bepridil discontinuation. Results: After excluding patients who were unable to maintain sinus rhythm during bepridil administration (n=18), and those who disagreed to bepridil discontinuation (n=17), 95 patients were divided into the short-term continuation (bepridil discontinued for <6 months [median 3.0 months] after CA [n=63]), and long-term continuation (bepridil discontinued for >6 months [median 11.4 months] after CA [n=32]) groups. During the mean follow-up period of 28±15 months, the groups showed a similar incidence of recurrent AF after bepridil discontinuation. In the long-term continuation group, 13 patients had recurrence, with 8 (62%) cases occurring within 4 months after discontinuation. A multivariate Cox regression analysis revealed that left atrial (LA) reverse remodeling (>15% decrease in LA volume index at 6 months) was an independent predictor of recurrent AF after CA (p<0.01). Conclusions: Long-term bepridil administration after CA did not affect the recurrence of AF after discontinuation. The assessment of LA reverse remodeling may be useful for decision-making regarding the discontinuation of antiarrhythmic drugs after CA.

Introduction: The significance of high precordial electrocardiograms in idiopathic ventricular fibrillation (IVF) is unknown. Method: This study included 50 consecutive patients (48 men; age, 42±18 years) who had spontaneous ventricular fibrillation not linked to structural heart disease and received implantable cardiac defibrillator therapy. IVF was diagnosed in 35 patients and Brugada syndrome was diagnosed in other 15 patients. Electrocardiograms in high intercostal space were compared between 35 patients with IVF and 105 age- and sex-matched healthy controls (patient: control ratio, 1:3). Results: The frequency of J point elevation ≥ 0.1mV in the 4th intercostal spaces was similar between patients with IVF (14%) and healthy controls (7%). However, the frequency of J point elevation ≥ 0.1mV in the 3rd intercostal space was higher in patients with IVF (40%) than controls (11%) (P < 0.01). J point elevation was present only in the 3rd intercostal space but not in the 4th intercostal space in 30% of patients with IVF but only in 6% of controls (P < 0.01). During follow up, the recurrence of ventricular fibrillation was higher in patients with IVF who had J point elevation in the 3rd intercostal space (36%) and Brugada syndrome(40%) than those with IVF who did not have J point elevation in the 3rd intercostal space.(11%) (P < 0.05 for both). Conclusion: J point elevation in the 3rd intercostal space was associated with IVF and recurrences of ventricular fibrillation. Electrocardiogram recordings in the high intercostal space may be useful to identify risk of sudden death.