BORDEAUX, FRANCE. It is generally accepted that experiencing one or more afib episodes in the first month following a pulmonary vein isolation (PVI) procedure (early recurrence) is not a good sign and may indicate that the ablation was not successful. Thus, the question arises, "Should patients who experience episodes of AF (or atrial tachycardia) shortly after their first ablation be re-ablated within the first month, or would it be better to wait at least 3 months before undergoing a repeat ablation?" A recent trial carried out at the Hopital Cardiologique du Haut-Leveque set out to answer this question.
The trial included 302 afib patients who had their first PVI between January 2004 and September 2007. The average age of the patients was 55 years and about 82% were male. Most of the patients (83%) would be classified as having lone atrial fibrillation and were about evenly split between paroxysmal and persistent afibbers. All trial participants underwent a PVI guided by electrophysiological mapping (Haissaguerre method) as well as a cavotricuspid isthmus ablation to prevent post-procedure right atrial flutter. Additional focal ablations and linear lesions were applied as necessary to achieve non-inducibility of AF by burst pacing at the end of the procedure.
Of the 302 patients ablated, 144 (48%) experienced no recurrence during the first month and received no further follow-up. NOTE: An early recurrence was defined as an episode of AF, atrial tachycardia, or ectopic activity lasting 3 minutes or more. Early recurrence was significantly associated with a lower left ventricular ejection fraction (60% vs. 65%) and longer duration of AF (87 months vs. 61 months). Of the remaining 158 patients with early recurrence, 7 could not be followed up for various reasons. Thus, 151 patients were available for the study to determine the merits, or otherwise, of repeat ablation within the first month following the initial procedure.
A total of 61 patients underwent an early re-ablation. After an 11-month follow-up, 49% experienced no further afib or tachycardia episodes. Among the 90 patients with early recurrence who did not undergo an early re-ablation, only 9% experienced no further arrhythmia incidence, with the remaining 91% requiring a repeat procedure. As far as a third procedure is concerned, this was needed by 36% of the group undergoing the early re-ablation and by 33% of the group undergoing late re-ablation.
Overall, the early re-ablation group underwent an average of 2.5 procedures, while the late re-ablation group underwent 2.2 procedures on average. The indication for a second ablation for AF was 50% of cases, atrial tachycardia was 46%, and incessant atrial ectopy was 4% of cases. The Bordeaux researchers conclude that the vast majority (91%) of afibbers who experience a recurrence within the first month after their initial PVI will have late occurrences as well. They also state that,
"Contrary to current thinking, early re-ablation within the first month is not deleterious, as there are fewer clinical recurrences compared with patients without early re-ablation. In all patients who have a second procedure, whether early or late, the rate of further ablation for clinical recurrences was the same; however, the total number of needed ablations was significantly higher in patients with early re-ablation".
The following statement from the report is also of interest:
"Radiofrequency ablation has a proinflammatory effect leading to cellular dysfunction and is potentially pro-arrhythmogenic. Moreover, AF ablation modifies the autonomic nervous system by reducing vagal activity and increasing sympathetic activity that may explain these ER (early recurrences) after the procedure, due to changes on the atrial substrate".
Lellouche, N, et al. Early recurrences after atrial fibrillation ablation: prognostic value and effect of early reablation. Journal of Cardiovascular Electrophysiology, Vol. 19, June 2008, pp. 599-605
Editor's comment: The initial procedure success rate reported here (48%) for the Bordeaux group is in line with the 46% reported in the 2007 ablation survey. The complete success rate after a second follow-up ablation would appear to be 83%, which is somewhat better than the 73% observed in our survey.