NPPB and acute myocardial infarction: A relevant study indicated that lyophilized recombinant human brain natriuretic peptide had a significant effect in improving cardiac function and flow-mediated dilatation (FMD).9 Based on the above studies, this study aimed to analyze the influence of lyophilized recombinant human brain natriuretic peptide on the basis of the conventional treatment on the vascular endothelial function of patients with acute myocardial infarction.