Background: Myeloperoxidase (MPO) has been associated with the development of atrial fibrillation (AF), but its impact on the recurrence of AF after catheter ablation has not been explored. This study investigated the effect of plasma MPO on recurrence after catheter ablation of paroxysmal AF.
Methods and Results: Two hundred eighty-eight consecutive patients with paroxysmal AF and who underwent circumferential pulmonary vein isolation were prospectively enrolled. After a mean ± SD follow-up of 516 ± 204 (91–910) days, the recurrence rates were 16.9%, 25.7%, 29.7%, and 38.0% from the lowest MPO quartile to the highest MPO quartile, respectively (P = 0.023). After adjustment for age, sex, left atrial diameter, high-sensitivity C-reactive protein, and pulmonary vein isolation, there was an increased risk of recurrence in the subjects with the highest MPO quartile compared with those with the lowest quartile (hazard ratio, 3.18; 95% confidence interval, 2.12–5.23; P = 0.024). As a continuous variable, MPO was also an independent predictor of recurrence (hazard ratio, 2.12; 95% confidence interval, 1.71–3.27; P = 0.032).
Conclusions: Patients with high MPO levels were at an increased risk of AF recurrence after catheter ablation.