Background: Several studies have provided details of left atrial anatomy by means of the image integration techniques, particularly focusing on the atypical patterns of the pulmonary veins.
Objective: To compare, in a prospective, randomized fashion, the conventional method of pulmonary vein disconnection and the image integration-guided approach.
Methods: Two hundred and ninety consecutive patients (290 patients, mean age 55 +/- 11 years) with drug-refractory paroxysmal or persistent atrial fibrillation were enrolled in the study and were divided into two treatment groups: group 1 (145 patients) undergoing an imaging integration-guided (CartoMerge TM) ablation; group 2 (145 patients) treated by a conventional radiofrequency catheter ablation procedure. The arrhythmia was refractory to at least two antiarrhythmic drugs (IC, amiodarone).
Results: Electrical disconnection of all identified pulmonary veins was obtained in all patients of both groups. Bidirectional block of the cavotricuspid isthmus was achieved in 34 group 1 patients and in 40 group 2 patients. Left mitral isthmus ablation was attempted in 52 group 1 patients and in 56 group 2 patients. At a mean follow-up of 14 +/- 12 months, the atrial fibrillation-free survival rate was significantly higher in group 1 patients compared with group 2 patients (88% vs 69%, P = 0.017). The analysis for the subset of patients with previously ineffective ablation (98 patients: 52 group 1 patients and 46 group 2 patients) showed a significantly lower recurrence rate in group 1 versus group 2 (19% vs 48%, P < 0.01).
Conclusions: Our data indicate a superior efficacy of the image-integration guided catheter ablation of atrial fibrillation over the long term.