Clinical impact of high-density mapping on the acute and long term outcome of atypical atrial flutter ablations

Purpose We evaluated the clinical impact of the high-density (HD) mapping compared with the standard low-density (LD) ablation catheter mapping technique in the treatment of AFLs. Methods We retrospectively evaluated short and long outcomes of patients approached with an HD and a LD electro-anatomical strategy for atypical AFLs. Results Eighty-seven patients were included. Patients were almost male (60%), relatively old (65 +/- 8 years), with a moderate CHA2DS2Vasc score (2.3 +/- 1.3), a preserved ejection fraction (58 +/- 6), and moderate atrial dilatation (44 +/- 7 mm). Baseline clinical characteristics were comparable between groups (p = NS). Among AFLs, 10 (11%) were located in the right and 78 (89%) in the left atrium, including 22 (28%) roof dependent and 37 (47%) mitral dependent (p = NS). Sinus rhythm restoration during ablation was more frequently observed in the HD group (79% vs 56%, p = 0.037), without differences in mapping time, procedural time, and radiological dose (p = NS). Overall AFL/AT/AF recurrence rate at 1, 2, and 3 years was lower in the HD group (14% vs 37% p = 0.02, 14% vs 48% p = 0.002 and 14% vs 50% p < 0.001, respectively) with a time-dependent trend only in the LD group (37% vs 48% vs 50% at 1, 2, and 3 years respectively, p = 0.059). HD mapping (OR 0.17; 95% CI 0.04-0.66) and younger age (OR 1.09; 95% CI 1.01-1.19) resulted independent predictors of overall arrhythmias at follow-up. Conclusions Short- and long-term outcomes of atypical AFL ablation were better in the case of HD mapping, which resulted independent predictor of arrhythmia recurrences.