Catheter Ablation of Atrial Fibrillation Raises the Plasma Level of NGF-β Which Is Associated with Sympathetic Nerve Activity.

PURPOSE

The expression of nerve growth factor-β (NGF-β) is related to cardiac nerve sprouting and sympathetic hyper innervation. We investigated the changes of plasma levels of NGF-β and the relationship to follow-up heart rate variability (HRV) after radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF).

MATERIALS AND METHODS

This study included 147 patients with AF (117 men, 55.8±11.5 years, 106 paroxysmal AF) who underwent RFCA. The plasma levels of NGF-β were quantified using double sandwich enzyme linked immunosorbent assay method before (NGF-βpre) and 1 hour after RFCA (NGF-βpost-1 hr). HRV at pre-procedure (HRVpre), 3 months (HRVpost-3 mo), and 1 year post-procedure (HRVpost-1 yr) were analyzed and compared with plasma levels of NGF-β.

RESULTS

1. The plasma levels of NGF-β significantly increased after RFCA (20.05±11.09 pg/mL vs. 29.60±19.43 pg/mL, p<0.001). The patients who did not show increased NGF-βpost-1 hr were older (p=0.023) and had greater left atrial volume index (p=0.028) than those with increased NGF-βpost-1 hr. 2) In patients with NGF-βpre>18 pg/mL, low frequency components (LF)/high-frequency components (HF) (p=0.003) and the number of atrial premature contractions (APCs, p=0.045) in HRVpost-3 mo were significantly higher than those with ≤18 pg/mL. 3) The LF/HF at HRVpost-3 mo was linearly associated with the NGF-βpre (B=4.240, 95% CI 1.114-7.336, p=0.008) and the NGF-βpost-1 hr (B=7.617, 95% CI 2.106-13.127, p=0.007). 4) Both NGF-βpre (OR=1.159, 95% CI 1.045-1.286, p=0.005) and NGF-βpost-1 hr (OR=1.098, 95% CI 1.030-1.170, p=0.004) were independent predictors for the increase of LF/HF at HRVpost-3 mo.

CONCLUSION

AF catheter ablation increases plasma level of NGF-β, and high plasma levels of NGF-βpre was associated with higher sympathetic nerve activity and higher frequency of APCs in HRVpost-3 mo.