Background: The significance of the inducibility of atrial fibrillation (AF) after pulmonary vein isolation (PVI) in patients with AF remains disputable and polarizing. Therefore, we investigated the prognostic value of the inducibility of AF on long-term outcome after PVI in patients without low-voltage left atrial (LA) substrate.
Methods: Two hundred forty-five patients (mean age 59+/-9years, 72% male) without LA low-voltage areas (defined as electrogram amplitudes <0.5 mV) undergoing first PVI procedure were included in the study. Following successful PVI, inducibility was assessed by burst pacing from coronary sinus with a cycle length (CL) of 300, 250, and 200 ms or the shortest CL resulting in 1:1 atrial capture. During the follow-up period of up to 3 years, the rhythm outcome was monitored by serial 7-days Holter electrocardiogram.
Results: AF was induced in 38 patients (16%). Atypical atrial flutter was observed in six patients (2%), while typical flutter in three cases (1%). Within the first 3 months, early recurrence was diagnosed in 39 patients (16%), while late recurrence was detected in 58 patients (24%) after a mean AF free survival of 28 ± 1 months. While there was no impact on early recurrence, AF inducibility affected long-term recurrence (31 ± 1 vs 23 ± 3 months; P = .001). In multivariate analysis, AF inducibility (hazard ratio [HR] 2.14; 95% confidence interval [CI], 1.03-4.45; P = .041) and persistent type of AF (HR 2.17; 95%CI, 1.06-4.47; P = .034) were associated with late AF recurrence.
Conclusion: In patients without low-voltage substrate undergoing PVI, AF inducibility is a significant predictor of long-term outcome. The pathomechanisms of this phenomenon must be further studied to be addressed by additional treatment.
Keywords: ablation; atrial fibrillation; atrial flutter; inducibility; outcome; pulmonary vein isolation.
© 2019 Wiley Periodicals, Inc.