CCL2 and atrial fibrillation: An increased expression then occurs of various inflammatory cytokines and chemokines such as: interleukin-1 and -6, tumour necrosis factor α (TNF-α) or monocyte chemoattractant protein 1 (MCP-1) and, in consequence, a progression of chronic atrial fibrillation and AF recurrences after cardioversion are observed [24].