Abstract
Left atrial circumferential ablation （LACa） and box ablation （BOXa） are two common treatments for paroxysmal atrial fibrillation （PAF）. However, only a few studies have compared these two approaches. This study aimed to compare the clinical outcomes of these two therapeutic modalities. Patients with PAF who underwent catheter ablation were randomly assigned to either the LACa or BOXa groups and were followed up for 6 months. The primary outcomes were the rate of atrial fibrillation （AF） recurrence after 6 months and changes in the left atrial ejection fraction （LAEF） measured via magnetic resonance imaging from baseline to follow-up. The secondary outcomes included the frequency of supraventricular premature beats （SPBs） and short supraventricular runs （SVRs） on a 24-h electrocardiogram at follow-up. A total of 40 patients were randomly assigned to the LACa （n＝21） or BOXa group （n＝19）. No significant between-group differences were observed in the patient characteristics and LAEF at baseline or the rate of AF recurrence at 6 months （LACa, 4.8％ ［1/21］ vs. BOXa, 5.3％ ［1/19］; P＝0.94） as well as changes in the LAEF at 3 and 6 months. However, the frequency of SPB and SVR at 6 months was significantly lower in the LACa group than in the BOXa group （0.2 ［−0.2, 0.50］/24h vs. 0.8 ［0.5, 1.2］/24h, P＝0.01; 2.2 ［−4.2, 8.7］/24h vs. 11.9 ［4.8, 18.9］/24h, P＝0.04, respectively）. Although the rates of AF recurrence and changes in the LAEF were comparable between the LACa and BOXa groups, the higher incidence of SPBs and SVRs at 6 months in the BOXa group suggests that BOXa provided no advantage in the treatment of PAF patients.
