PCSK9 and acute myocardial infarction: This study examined the anti-inflammatory and endothelial function-enhancing effects of proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitor therapy in the early phase after acute myocardial infarction (AMI) by assessing changes in tumor necrosis factor-α (TNF-α) levels and the l-arginine/asymmetric-dimethylarginine (ADMA) ratio.