Usefulness of atrial fibrillation burden as a predictor for success of pulmonary vein isolation.

Background: The definition of symptomatic improvement after pulmonary vein isolation (PVI) is controversial. We assessed primarily the usefulness and predictive accuracy (PA) of AF (atrial fibrillation) burden (AFB) within the first 3 months after the procedure as an early predictor for curative success as well as reduction of symptoms.
Methods: We studied 100 pts (62 men, mean age: 54 +/- 9 years, LVEF: 57 +/- 9%, paroxysmal AF, 85, persistent AF, 15) who underwent PVI. RF ablation was used in 63 patients. The combination of cryoablation and RF (Hybrid therapy) was used in the remaining 37 patients, in 19 patients of whom additionally linear lesions were performed. All patients were followed up 3 months after PVI (the blanking period) and every 3 months thereafter. The significance of early recurrence of AF (ERAF) was separately analyzed for RF and for hybrid therapy arm. Quality of life (QoL) was assessed using the physical composite summary score (PCS) and mental composite summary score (MCS). AFB was dichotomized at: 0, 0.5, 1, 6, 12, and 24 hours.
Results: ANOVA revealed significant differences between PCS at baseline and after PVI in patients without recurrence and with those with postablation AFB <12 hours. There was no difference between PCS in patients with AFB > or =12 hours within a 3 months interval and PCS at baseline. ERAF occurred in 35% of patients (16 patients, AFB > or =12 hours). Symptomatic ERAF occurred in 29 patients (17 patients AFB > or =12 hours). After the blanking period, documented AF recurrence was found in 50 patients (17 patients, AFB > or =12 hour). Symptomatic late recurrence was found in 47 patients (31 patients with AFB > or =12 hours). Absence of ERAF was revealed to be predictive for long-term success and symptomatic ERAF was found to be predictive for symptomatic AF recurrence (P <0.0001).
Conclusion: AF recurrence with AFB > or =12 hours within 3 months is associated with a missed improvement of QoL. Symptomatic ERAF predicts recurrence independently of therapy.