Catheter ablation of atrial fibrillation: Radiofrequency catheter ablation for redo procedures after cryoablation

摘要

AIM: To evaluate the effectiveness of two different strategies using radiofrequency catheter ablation for redo procedures after cryoablation of atrial fibrillation.METHODS: Thirty patients(paroxysmal atrial fibrillation: 22 patients,persistent atrial fibrillation: 8 patients) had to undergo a redo procedure after initially successful circumferential pulmonary vein(PV) isolation with the cryoballoon technique(Arctic Front Balloon,CryoCath Technologies/Medtronic).The redo ablation procedures were performed using a segmental approach or a circumferential ablation strategy(CARTO;Biosense Webster) depending on the intra-procedural findings.After discharge,patients were scheduled for repeated visits at the arrhythmia clinic.A 7-day Holter monitoring was performed at 3,12 and 24 mo after the ablation procedure.RESULTS: During the redo procedure,a mean number of 2.9 re-conducting pulmonary veins(SD ± 1.0 PVs) were detected(using a circular mapping catheter).In 20 patients,a segmental approach was sufficient to eliminate the residual pulmonary vein conduction because there were only a few recovered pulmonary vein fibres.In the remaining 10 patients,a circumferential ablation strategy was used because of a complete recovery of the PV-LA conduction.All recovered pulmonary veins could be isolated successfully again.At 2-year follow-up,73.3% of all patients were free from an arrhythmia recurrence(22/30).There were no major complications.CONCLUSION: In patients with an initial circumferential pulmonary vein isolation using the cryoballoon technique,a repeat ablation procedure can be performed safely and effectively using radiofrequency catheter ablation.