MiRNA21 and IL-18 levels in left atrial blood in patients with atrial fibrillation undergoing cryoablation and their predictive value for recurrence of atrial fibrillation.

Purpose: The recurrence of atrial fibrillation (AF) after cryoablation still needs to be prioritized, including discriminating predictive indicators.

Methods: Eighty-seven patients aged 43-83 years who underwent cryo-balloon ablation were divided into paroxysmal atrial fibrillation (PAF) and non-paroxysmal atrial fibrillation (non-PAF) groups. Baseline data, intraoperative index, and miRNA21, IL-18, NLRP3, and visfatin levels in peripheral venous blood and left atrial blood were assessed. Follow-up was performed for 6 months to observe the recurrence of AF. A Cox risk ratio model was used to analyze indicators for predicting AF recurrence.

Results: The non-PAF and PAF group recurrence rates of AF were statistically different (p < 0.05) at 9/22 (40.9%) and 11/65 (16.9%), respectively. Biomarker levels in the left atrial blood were higher in the non-PAF group than in the PAF group (p < 0.05). The effects of non-PAF and levels of miRNA21 and IL-18 in left atrial serum on the recurrence of AF after cryoablation statistically differed (p < 0.05).

Conclusion: The levels of miRNA21 and IL-18 were higher in left atrial blood than in peripheral blood, which may be related to the severity of AF and recurrence of AF after cryoablation.