Red blood cell distribution width predicts outcome of cryoballoon-based atrial fibrillation ablation

Elevated red blood cell distribution width (RDW) has been associated with atrial fibrillation (AF) in cross-sectional and prospective studies. In this study, we aim to evaluate the relation of preablation RDW levels to late AF recurrence following cryoablation.

A total of 299 patients with symptomatic paroxysmal or persistent AF despite ≥ 1 antiarrhythmic drug(s) who were scheduled for cryoballoon-based AF ablation were enrolled in this prospective study.

A total of 299 patients (55.40 ± 10.60 years, 49.20 % male) were involved and followed up at a median time of 24 (6-44) months. Patients with late AF recurrence had higher RDW levels (14.30 ± 0.93 vs. 13.52 ± 0.93 %, p < 0.001). Multivariate Cox proportional hazard regression analysis showed that RDW level was an independent predictor for late AF recurrence (HR 1.88, 95 % CI 1.41-2.50, p < 0.001) along with left atrial (LA) diameter (HR 3.09, 95 % CI 1.81-5.27, p < 0.001), duration of AF (HR 1.04, 95 % CI 1.01-1.07, p = 0.02), and early AF recurrence (HR 6.39, 95 % CI 3.41-11.97, p < 0.001). A cut-off level of 13.75 % for RDW predicted late AF recurrence following cryoballoon-based pulmonary vein isolation (PVI) with a sensitivity and specificity of 78.00 and 70.00 %, respectively.

These findings suggest that elevated RDW may be a predictor of late recurrence following cryoballoon-based AF ablation. Further studies are needed to establish its exact pathophysiologic and prognostic roles.