MMP8 and atrial fibrillation: Proinflammatory neutrophil-derived AF biomarkers (Cascade 1) associated with general inflammatory biomarker CRP in IAI cases though suggesting that activated and degranulating neutrophils are the major source of MMP-8 and MMP-9, MPO (Cascade 1), and HNE (Cascade 2) in the AF affected by MIAC.