Different characteristics and electrophysiological properties between early and late recurrences after acute successful catheter ablation of idiopathic right ventricular outflow tract arrhythmias during long-term follow-up

Background Radiofrequency catheter ablation (RFCA) is an effective therapeutic strategy in eliminating drug-refractory idiopathic right ventricular outflow tract ventricular arrhythmias (RVOT VAs). It remains unclear what factors affect early and late VA recurrences after ablation. Objective The aim of our study was to elucidate the differences between early and late recurrences after acute successful RFCA of RVOT VAs in a long-term follow-up. Methods A total of 220 patients with acute successful RFCA of RVOT VAs were enrolled. Detailed clinical characteristics and assessments by noninvasive and invasive electrophysiology study were explored to predict the overall, early (≤1 year), and late VA (>1 year) recurrences. Results During a mean follow-up of 34.15 ± 33.74 months, 45 of 220 patients (20.5%) documented recurrence of RVOT VAs after the initial RFCA. Of these patients, 26 patients (57.8%) with recurrent VAs showed similar morphology, and 19 (42.2%) were different. Patients with recurrent VAs were associated with a higher incidence of hypertension, higher systolic blood pressure, identification of foci by pace mapping alone, shorter earliest activation time, more radiofrequency pulses required, and VA originating from the anterior free wall. Multivariate analysis demonstrated that mapping strategy and shorter earliest activation time preceding VA were associated with early recurrences (hazard ratio [HR] 2.26; 95% confidence interval [CI] 1.49-3.42; P ;lt and HR 0.91; 95% CI 0.85-0.98; P =.008, respectively), whereas hypertension was associated with late recurrence (HR 3.48; 95% CI 1.34-9.07; P =.001). Conclusion RFCA is an effective strategy in the elimination of RVOT VAs. However, early and late recurrences occur commonly. Patients with early and late VA recurrences demonstrated nonuniform patterns of clinical characteristics and electrophysiological properties.