Impact of Atrial Fibrillation and Sinus Rhythm Restoration on Reticulated Platelets

Objective: To assess the impact of nonvalvular atrial fibrillation (NVAF) and sinus rhythm restoration on the distribution of reticulated platelets (RPs), which are known to be associated with thrombotic propensity and have a greater predilection for thrombus participation. Participants and Methods: The RP content was assessed by flow cytometry (thiazole orange/CD61) in 110 consecutive patients with NVAF before and 3 to 4 months after catheter ablation of the pulmonary veins. Results were compared with those of 55 age-and sex-matched controls with normal sinus rhythm. Results: The mean +/- SD percentage of RPs was higher in patients with NVAF compared with controls (28.5%+/- 7.3% vs 6.4%+/- 5.3%; P<.001). The RP content did not vary by CHA(2)DS(2)-VASc score. After catheter ablation of the pulmonary veins, 63 patients were available for follow-up assessment. A significant reduction of RPs was observed compared with preintervention values (29.85%+/- 7.1% vs 20.79%+/- 7.6%; P<.001). During follow-up, 19% of patients (12 of 63) had confirmed AF recurrence. The mean +/- SD percentage of RPs was higher in this group than in those without a recurrence (24.7%+/- 6.5% vs 18.9%+/- 7.5%; P=.01). Conclusion: Nonvalvular atrial fibrillation affects the percentage of RPs, independent of the CHA(2)DS(2)-VASc score. After ablation, RP content dropped significantly. High RP content in patients with NVAF may explain the potential mechanism of thromboembolic complications and the lack of efficacy of currently available antiplatelet therapy for stroke prevention in this dysrhythmia. (C) 2015 Mayo Foundation for Medical Education and Research