Tolga Aksu, Erkan Baysal, Tümer Erdem Guler, Sukriye Ebru Golcuk, İsmail Erden, Kazim Serhan Ozcan

Cryoballoon ablation (CA) is a safe and efficient method for pulmonary vein isolation in the treatment of paroxysmal atrial fibrillation (AF). There are conflicting results about the predictors of AF recurrence. The aim of this study is to evaluate the role of hematological indices to predict AF recurrence after CA. A total of 49 patients (mean age 58.3±12.2 years, 51.02% female) with symptomatic paroxysmal AF underwent CA procedure. One hundred and sixty-eight pulmonary veins were used for pulmonary vein isolation with the second-generation cryoballoon. The hematological samples were obtained before and 24 hours after ablation. At a mean follow-up of 10.2±2.4 months, the probability of being arrhythmia-free after a single procedure was 86%. Patients with AF recurrence had higher red cell distribution width levels (16.10%±1.44% vs 14.87%±0.48%, P=0.035). The neutrophil/lymphocyte ratio, erythrocyte sedimentation rate, and C-reactive protein levels were detected in the patients with or without recurrence. Left atrial diameter (46.28±4.30 mm vs 41.02±4.10 mm, P=0.002), duration of AF (6.71±4.57 years vs 3.59±1.72 years, P=0.003), and age (65.01±15.39 years vs 54.29±11.32 years, P=0.033) were the other independent predictors of clinical recurrence after CA. Multiple regression analysis revealed that left atrial diameter was the only independent predictor for AF recurrence (P=0.012). In this study of patients with paroxysmal AF undergoing cryoablation, increased preablation red cell distribution width levels, and not C-reactive protein or erythrocyte sedimentation rate, was associated with a higher rate of AF recurrence. Our results support the role of a preablation, proinflammatory, and pro-oxidant environment in the development of AF recurrence after ablation therapy but suggest that other factors are also important.