Atrial fibrillation recurrence after catheter ablation is associated with RAD51 and p63 proteins

Catheter ablation has been demonstrated to reduce atrial fibrillation (AF) recurrence. The mechanisms of AF recurrence after catheter ablation are unknown, and the present study aimed to identify serum proteins associated with AF recurrence. The present prospective study comprised a cohort of patients with AF, which was divided into two groups after one-year follow-up: group 1 included patients with compensated AF after catheter ablation and group 2 included patients with AF recurrence after catheter ablation. Initial microarray profiling of the serum proteins was performed in small subgroups M1 and M2 recruited from groups 1 and 2, respectively, by an antibody microarray to evaluate potentially relevant proteins. The data of initial proteomic profiling identified candidate proteins in groups 1 and 2, and their levels were then measured by ELISA. The data of profiling suggested an overall increase in the levels of RAD51 and p63 proteins in the M2 subgroup versus that in the M1 subgroup, indicating potential relevance of these two proteins to AF recurrence. The results of ELISA of the levels of RAD51 and p63 in the groups 1 and 2 demonstrated an increase in the levels of RAD51 (11.11 ± 4.36 vs 8.45 ± 4.85 ng/mL; P = 0.009) and p63 (165.73 ± 113.75 vs 100.05 ± 37.56 units of normalized optical density; P = 0.0007) in the group 2 (with AF recurrence or substrate AF) compared with that in the group 1 (compensated AF). Thus, RAD51 and p63 were associated with AF recurrence after catheter ablation and may represent possible etiological factors for subsequent outcomes.