Introduction
Atrial fibrillation (AF) is the most common sustained arrhythmia observed in clinical practice. It can occur even in the absence of heart disease and is associated with a significant burden on patients and healthcare. Recently, it has been suggested that rhythm control therapy, including antiarrhythmic drugs (AADs) and catheter ablation (CA), may prevent not only subjective symptoms such as palpitations and shortness of breath but also AF-related death, heart failure, and stroke in high-risk patients.1 However, in patients with an enlarged left atrium (LA), the sinus rhythm maintenance rate is reported to be only 40–60%.2,3 A large number of patients are treated with AADs in combination with CA for refractory AF.4 Bepridil is effective in terminating long-lasting persistent AF,5 and is recommended as the standard AAD for rhythm control in persistent AF in the guidelines for AF.6 However, it is unclear how long bepridil in combination with CA should be continued and the benefits of long-term administration remain to be determined. Prolonged use of bepridil sometimes causes remarkable QT prolongation and life-threatening arrhythmias, including torsades de pointes, particularly in the elderly.7
In some cases of AF, the LA size decreases after rhythm control, which is considered to indicate LA reverse remodeling.8 In addition, previous experimental studies have suggested that bepridil has a reverse electrical remodeling effect.9,10 LA reverse remodeling could lead to favorable outcomes in the late phase.11,12 In this study, we investigated the differences in post-ablation outcomes depending on the duration of the concomitant use of bepridil, and the impact of LA reverse remodeling on maintenance of sinus rhythm after hybrid therapy consisting of CA and bepridil.