The percentages of 1+ cells of GFRA2 in the AF and NP in the advanced stage (AF: 40.6 ± 6.2%; NP: 40.2 ± 3.5%) were significantly higher than those in the AF and NP in the early stage of degeneration (AF: 19.1 ± 3.2%; NP: 14.2 ± 1.9%, p < 0.01, Figure 11b). Here, GFRA2 is linked to atrial fibrillation.