Collagen volume, activity of nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB, a crucial inflammatory signaling transcription factor) (Qu et al., 2009) and serum levels of fibro-inflammatory biomarkers are all elevated in persistent-AF (Sonmez et al., 2014) and post-ablation AF recurrence (Okumura et al., 2011). This evidence concerns the gene NFKB1 and atrial fibrillation.