Characterization of Neutrophil Extracellular Traps in Acute Myocardial Infarction: A Translational Study.

Neutrophil extracellular traps (NETs) are implicated in thrombosis and inflammation during acute myocardial infarction (AMI), but their kinetics, local distribution, and clinical relevance remain unclear. We conducted a prospective study in 144 patients with ST-segment elevation (STEMI) and non-ST-segment elevation AMI (NSTEMI) undergoing coronary angioplasty (PCI), quantifying double-stranded DNA (dsDNA), myeloperoxidase (MPO), and neutrophil elastase (NE) in the infarct-related artery (IRA), contralateral coronary artery (CCA), and peripheral blood. Coronary thrombi and DNASE1 Q222R were also analysed. NET markers were elevated in the IRA, and NE and dsDNA increased peripherally after PCI. IRA NE levels independently predicted cardiovascular events (HR, 1.76; 95%CI: 1.24 - 2.51). Thrombi with higher NE and citrullinated histone H3 content were associated with suboptimal PCI results. dsDNA levels were significantly higher in patients with the GG DNASE1 genotype. These findings indicate a compartmentalized NET response in AMI and support a potential prognostic impact of NETs.