RESUMO
AIMS: The aim is a description of the recurrent arrhythmias after previous ablation of paroxysmal atrial fibrillation (AF), and the results of a repeat catheter ablation. METHODS: A repeat ablation was performed in 76 patients (18 females, 54 +/- 11 years) in 96 procedures, which was 21% out of 362 patients, who had undergone the first ablation for a paroxysmal AF. The endpoints of the repeat ablation were re-isolation of the pulmonary veins (PV) and termination of a spontaneous or induced arrhythmia and restoration of a stable sinus rhythm (SR), and possibly achievement of noninducibility of any arrhythmia. RESULTS: Clinical left atrial tachycardia (LAT) was present in 10 (13%) patients before the first, and in 5 (25%) patients before the second repeat ablation. Arrhythmia arising from an arrhythmogenic PV due to the conduction recovery into the left atrium (LA) was found in 50 (66%) patients during the first, and in 7 (35%) patients during the second repeat ablation. Arrhythmias, predominantly of the reentry mechanism and originating in the LA free wall, were found in 26 (34%), respectively 13 (65%) during the first or the second repeat ablation. All arrhythmias from PVs were terminated by a PV encircling ablation. Substrate-related arrhythmias were terminated by ablation except for 2 (3%) patients during the first and 3 (15%) patients during the second repeat ablation. Persistent AF was mainly terminated via conversion into a LAT. In these cases, the ablation sites leading to the SR restoration were, similarly to the primary LATs, located predominantly in the LA anterior wall. During the 22 +/- 13 months follow-up, 68 (89%) patients were free of AF, 54 (71%) patients off the antiarrhythmic drugs and 14 (18%) patients with the class I or III antiarrhythmic drugs. CONCLUSION: AF associated with PV-LA re-connection dominated prior to the first repeat ablation, then the proportion of the substrate-related arrhythmias from the LA free wall increased. Clinical efficacy of the repeat ablation is high.
