Incidence of late recurrence of AF following PVI
MUNCHEN, GERMANY. Data regarding long-term success for pulmonary vein isolation (PVI) procedures are sparse. Most clinical trials only report success rates for 6 to 12 months post-procedure. A group of German electrophysiologists now reports on the long-term (up to 5 years) AF status of 356 paroxysmal afibbers who underwent a segmental PVI during the period 1998 – 2008.

Early recurrence (after a 90-day blanking period) was observed in 57% of the patients. However, only 6.7% experienced long-term recurrence if they had experienced normal sinus rhythm for a year after the initial PVI. The time to recurrence in this group of 24 patients ranged from 18 to 69 months following the initial PVI. Fourteen of the 24 patients underwent a repeat PVI with 8 patients receiving additional lesions as required. It is interesting that the electrophysiology study performed in the 14 patients showed reconnection between the left atrium and 43 of 48 initially isolated pulmonary veins.

After a further follow-up of 15 months, 71% of the re-ablated patients were in normal sinus rhythm. The authors conclude that very late recurrence (after a year or longer following the initial procedure) is relatively rare and that the success rate of a repeat procedure in this group is high.

Fichtner, S, et al. Very late relapse of atrial fibrillation after pulmonary vein isolation: incidence and results of repeat ablation. PACE, Vol. 33, October 2010, pp. 1258-63

Editor's comment: The 2009 Ablation/Maze Survey dealt with the long-term recurrence rate of AF episodes following an initially successful PVI procedure. Twenty-seven ablatees did not experience any arrhythmias during the first year following their procedure. At the end of year 4 recurrence rate in this group was 7% - very close to the 6.7% reported by the German group. Thus, it is clear that being arrhythmia-free during the first year post-procedure is an excellent indicator of long-term success. Being arrhythmia-free during the first year is, in turn, almost entirely dependent on the skill and experience of the EP performing the final ablation (p=0.036 in the 2009 Ablation/Maze Survey).