NPPB and respiratory failure: In summary, the present study reveals that several independent factors, including d-dimer, B-type Natriuretic Peptide (BNP), Systolic Blood Pressure (SBP), White Blood Cell Count (WBC), and postoperative respiratory failure, significantly impact in-hospital mortality in patients undergoing emergency Percutaneous Coronary Intervention (PCI) for Acute Myocardial Infarction (AMI).