Early recurrence and final ablation outcome
VIENNA, AUSTRIA. Early recurrence of afib (within 48 hours of procedure completion) is not uncommon following a pulmonary vein isolation (PVI) procedure. However, it is not known whether early recurrence is associated with a poorer long-term prognosis. EPs at the Medical University of Vienna completed a study to investigate this.

The study included 234 patients undergoing catheter ablation for symptomatic paroxysmal or persistent AF. The average age of the patients was 57 years, 72% were men and 71% had paroxysmal AF with 82% experiencing daily or weekly episodes. Twenty-two percent had structural heart disease, so the majority (78%) of the group would be classified as lone afibbers. Thirty-five percent of the group underwent a segmental PVI (Haissaguerre method), while the remaining 65% underwent an anatomically-guided (CARTO) circumferential PVI (Pappone method) including roof line and mitral isthmus line. Total procedure time was 173 minutes for the segmental procedure versus 142 minutes for the circumferential procedure with total fluoroscopy times of 64 and 46 minutes respectively.

Early afib recurrence (within 48 hours) was observed in 37% of the segmental group patients versus 46% in the circumferential group. After an average (median) follow-up of 12.7 months, 35% of study participants were free of afib without the use of antiarrhythmics, 23% were free of afib while on antiarrhythmics that had previously failed, and the remaining 42% still experienced episodes. Among paroxysmal afibbers, 64% were free of afib (with or without antiarrhythmics) at the end of the follow-up as compared to only 45% of persistent afibbers.

Early recurrence was a significant predictor of failure. Among paroxysmal afibbers, the long-term success rate (with and without antiarrhythmics) was 70% for those without early recurrence and 53% for those with early recurrence. Corresponding numbers for persistent afibbers were 59% and 32%. Early recurrence was a predictor of failure in both the segmental PVI group and in the circumferential group. Overall, ablated afibbers who experienced early recurrence experienced twice the risk of failure, as did those not experiencing early recurrence. However, the researchers emphasize that, despite this, 46% of those who experienced early recurrence still were free of afib at the end of the study period.

Richter, B, et al. Frequency of recurrence of atrial fibrillation within 48 hours after ablation and its impact on long-term outcome. American Journal of Cardiology, Vol. 101, 2008, pp. 843-47

Editor's comment: The success rates in this study are certainly not impressive (complete success rate of 35% after one procedure); however, there was no significant difference between the outcome of segmental (Haissaguerre) and circumferential (Pappone) procedures. It is of interest that the characteristics of the Vienna group – age at ablation: 57 years, male: 72%, and paroxysmal: 71% – are quite similar to those of the 516 afibbers responding to the 2007 ablation/maze survey. Here the average age at ablation was 56 years with 78% being male, and 78% being paroxysmal. The complete success rate achieved by the Austrian group (35%) is also very close to the average success rate (34%) found in the 2007 survey.