Milrinone versus dobutamine in acute myocardial infarction-related cardiogenic shock; a propensity score matched analysis

Background: Vasopressors and inotropes remain the cornerstone in treatment of acute myocardial infarction-related cardiogenic shock (AMI-CS). Milrinone and dobutamine are both commonly used, yet the optimal inotrope remains unclear. We aimed to identify factors associated with milrinone and dobutamine treatment and assess their effects on 30-day mortality in a large real-world cohort of AMI-CS patients. The Netherlands Heart Registration prospectively records data for percutaneous coronary intervention patients. Between 2017 and 2021, additional retrospective data on CS patients were collected by fourteen Dutch hospitals. Patients who were treated with either milrinone or dobutamine were selected; those treated with both were excluded. Missing data were imputed (30 ×) using multiple imputation, and propensity matched score analysis (PSM) was performed to evaluate the association between milrinone or dobutamine treatment and 30-day mortality. Results: In total, 739 patients were included (milrinone n = 247, dobutamine n = 492). Prior to matching, milrinone-treated patients exhibited more severely ill baseline and treatment characteristics, and higher 30-day mortality (50.6% vs. 41.5%, p = 0.018). After PSM, 198 patients remained in each group for analysis. Baseline characteristics were well balanced and 30-day mortality rates were similar (46.5% vs. 41.9%, p = 0.362). Conclusion: In this real-world propensity-matched cohort of AMI-CS patients, no significant difference in 30-day mortality was observed between patients treated with milrinone and dobutamine. Importantly, milrinone patients were more severely ill at baseline, indicating that the choice of inotrope may be influenced by illness severity. This comprehensive study suggests that the selection of inotrope may continue to be guided by individual patient characteristics.