Background: The catheter ablation of atrial fibrillation (AF) can be performed by ablation of complex fractionated atrial electrograms (CFAE). Endpoint of CFAE ablation is the regularisation or termination of AF. However, the impact of regular atrial tachycardia (AT) occurring during CFAE ablation on long term outcome has not been investigated. Thus, it is not clear whether these tachycardias should be acutely targeted for ablation.
Methods: In 43 patients (31 male, age 62±9 years with paroxysmal (15 patients), persistent (25 patietns) or permanent AF (3 patients) organisation of AF to regular AT was achieved by ablation of CFAE. Mapping of AT with subsequent successful ablation was performed in 14/43 patients (33%), in the remaining 29/43 patients (67%) AT was terminated with external cardioversion or pace overdrive. After ablation procedure, patients were seen in our out-patient clinic with repetitive Holter ECG after 1, 3, and subsequently every 3 months and were intensively screened for the occurrence of regular AT.
Results: In follow-up 22/43 patients (51%) developed sustained AT necessitating in 20 patients repeat catheter ablation (12 patients) or external cardioversion (8 patients). AF had been paroxysmal in 7/22 and persisten in 15/22 patients with AT in follow-up. In 14/22 patients (63%), no attempt for ablation of AT had been made during the initial procedure, in 8/22 AT (36%) had been mapped and initially successful ablated. Of 21 patients without AT occurrence during follow-up, AF had been paroxysmal in 8/21 and persistent or permanent in 13/21 patients. AT had been mapped and ablated in 6 (29%) whereas in 15/21 patients (71%), AT had not been targeted. Ablation of AT during initial procedure, number of ablation applications, procedure and fluoroscopy duration were not predictive for freedom of AT in follow-up.
Conclusion: In our study, mapping and successful ablation of new onset regular atrial tachycardias (AT) occurring during ablation of CFAE for atrial fibrillation was not predictive for the occurrence of AT in follow-up. Thus, results after termination of AT by cardioversion was in long-term comparable to sometimes time-consuming mapping/ablation for AT.
Clinical and Electrophysiological Variables Predictive of Favorable Outcome of Additional Ablation of Complex Fractionated Atrial Electrograms in Patients with Persistent Atrial Fibrillation
