Antimicrobial use was common in acute myocardial infarction (AMI)–related cardiogenic shock, despite low microbiological yield and limited detection of resistant organisms. In this multicenter registry analysis published in Journal of the American Heart Association, 1,095 patients from the Northwell-Shock Registry (2016-2022) were evaluated, excluding those undergoing coronary artery bypass grafting (CABG).

Antimicrobial use (AMU) was defined as ≥24 hours of continuous therapy, and patients were categorized into AMU-positive (AMU+) and AMU-negative (AMU−) groups. AMU was administered in 55% of patients, with 70% initiated within 48 hours of admission.
Microbiological yield remained low, with positive cultures identified in 12.6% of blood samples and 20.4% of urine samples.

Resistant organisms were detected in 9.5% of positive blood cultures. Despite negative cultures, AMU was prolonged in 70% of patients. Broad-spectrum agents were used in 84.9% of AMU+ patients, with more than 70% receiving anti–methicillin-resistant Staphylococcus aureus and antipseudomonal agents.

Length of stay was longer in AMU+ patients compared with AMU− patients (11 vs 4 days; P<0.01), while mortality was similar between groups (35.2% vs 37.2%; P=0.485). These findings highlight the need for targeted antimicrobial stewardship strategies to optimize AMU in AMI-related cardiogenic shock.