Antimicrobial Use in Acute Myocardial Infarction–Related Cardiogenic Shock

Background Antimicrobial use (AMU) in acute myocardial infarction–related cardiogenic shock is common, but its prevalence, drivers, and outcomes are not well described. Methods We analyzed 1095 patients with acute myocardial infarction–related cardiogenic shock from the multicenter Northwell‐Shock Registry (2016–2022). Patients undergoing coronary artery bypass surgery were excluded. AMU was defined as ≥24 hours of continuous therapy. Clinical features and outcomes were compared between AMU+ and AMU− groups. Results Antimicrobials were used in 55% of patients, and 70% of them were initiated within 48 hours of admission. Positivity was low in AMU+ cultures (12.6% blood, 20.4% urine), and resistant organisms were found in only 9.5% of positive blood cultures. In 70% of patients, AMU was prolonged despite negative cultures. Broad‐spectrum agents were used in 84.9%. Anti–methicillin‐resistant Staphylococcus aureus and antipseudomonal agents were used in >70% of patients with AMU. While length of stay was longer in AMU+ patients (11 versus 4 days, P <0.01), the overall mortality rate was similar (35.2% versus 37.2%, P =0.485). Conclusions More than half of patients with acute myocardial infarction–related cardiogenic shock received antimicrobials. Most patients received broad‐spectrum coverage despite low microbial culture yield and the rare isolation of resistant organisms. These findings highlight the need for targeted stewardship strategies to optimize AMU in acute myocardial infarction–related cardiogenic shock.