Background: Silent cerebral events (SCE) have been identified on cerebral diffusion-weighted cerebral magnetic resonance imaging (DE-MRI) after catheter ablation (CA) of atrial fibrillation (AF). The purpose of this study was to investigate the impact of atrial remodeling on the incidence of SCE after AF CA.
Methods: Forty patients (67.8 ± 10 years, 47.5 % women) with symptomatic paroxysmal (n = 11, 27.5 %) or persistent AF undergoing AF CA were prospectively enrolled. LA fibrosis was estimated by intraprocedural bipolar voltage mapping in sinus rhythm. Apoptosis-stimulating fragment (Fas-Ligand) and amino terminal peptide from collagen III (PIIINP) concentrations were analyzed of LA and femoral vein blood. Cerebral DE-MRI was performed 1 to 2 days after CA of AF for detection of SCE. In nine patients (22.5 %), new SCE were detected on DE-MRI after AF CA.
Results: Patients with SCE had higher CHA2DS2-VASc score, larger left atrial diameter (LADmax), and higher surface area of left atrial low-voltage (24 ± 11.2 vs 3.5 ± 4.2 %, p < 0.0001). Concentrations of peripheral PIIINP (103.7 ± 25.9 vs 81.8 ± 16.7 pg/ml, p < 0.01) and Fas-Ligand (124.1 ± 22.4 vs 87.6 ± 19.4 pg/ml, p < 0.01) were significantly higher in patients with SCE and correlated to low-voltage surface area (p < 0.01). Multivariable logistic regression analysis revealed peripheral Fas-Ligand, LADmax, CHA2DS2-Vasc score, and LA low-voltage area proportion to be independent predictors for the development of SCE.
Conclusions: LA remodeling, estimated by LADmax and LA low-voltage area, has significant relationship with the risk of SCE after AF ablation. Moreover, Fas-Ligand may act as an independent predictor for SCE in the context of AF CA.
Keywords: Atrial fibrillation; Atrial fibrosis; Catheter ablation; Silent cerebral events; Thromboembolic risk.