Dobutamine versus milrinone use in acute myocardial infarction related cardiogenic shock
Authors: Ten Berg S , Peters E J , Bogerd M , Timmermans M J C , Otterspoor L C , Vlaar A P J , Henriques J P S 
Published: November 2023

Abstract

Introduction
Even though dobutamine and milrinone are both commonly used in the treatment of cardiogenic shock (CS), there is little evidence guiding the selection of inotrope. Even in the randomized DOREMI trial, in which both drugs were compared in the setting of cardiogenic shock, no significant differences were found in any of the outcomes. As a result, the choice of inotrope is left to the discretion of the treating physician.

Purpose
In this real world data study, we aimed to retrospectively identify patient-, treatment- and outcome characteristics of patients treated with either dobutamine or milrinone in the context of acute myocardial infarction (AMI) complicated by CS.

Methods
In the Netherlands, baseline, procedural and outcome data on patients undergoing PCI are prospectively registered within the Netherlands Heart Registration (NHR). Additionally, all patients with CS undergoing PCI were included in a CS registry by fourteen Dutch hospitals between 2017 and 2021. Patients were classified into groups based on the administration of either dobutamine or milrinone, initiated in the first 24 hours after PCI. Patients who received both were excluded from further analyses.

Results
A total of 2328 consecutive CS patients were included of whom 503 (22%) and 267 (12%) patients received dobutamine and milrinone respectively. At baseline, patients in the dobutamine group had higher eGFR (60.7 vs. 56.7 ml/min, p=0.016) and had a lower BMI (26.7 vs. 27.7 kg/m2, p=0.009). At presentation, the dobutamine group had a significantly lower heart rate (82.7 vs. 96.1 beats/minute, p&lt;0.001) and presented more frequently with STEMI (86.1% vs. 73.4%). After PCI, administration of dobutamine was less often accompanied by noradrenaline (79.8% vs. 91.0%, p&lt;0.001). Notably, the milrinone group had an increase in lactate after PCI more often (19.3% vs. 36.7%, &lt;0.001), however it cannot be determined if the choice of drug was either influenced by the increase in lactate or if the lactate increased as a result of the initiation of the drug. Also, patients in the dobutamine group were less often intubated (53.3% vs. 64.4%, p=0.004) and less frequently supported by mechanical circulatory devices (32.8% vs. 41.2%, p=0.025). Lastly, 30-day mortality was significantly lower in the dobutamine group (41.7% vs. 50.8%, unadjusted p=0.020).

Conclusions
In this Dutch cohort of CS patients undergoing PCI, treatment and outcomes differed greatly between patient categories receiving either dobutamine or milrinone, most possibly due to differences in baseline characteristics. Importantly, patients treated with milrinone were sicker as was reflected by increase of lactate, higher heart rates at admission and higher rates of support by noradrenaline and mechanical devices. Therefore, in current practice, physicians seem to choose milrinone in more severe stages of shock. The results of this study demonstrate the need for implementation studies of available evidence.Kaplan Meier dobutamine vs. milrinoneTable dobutamine vs. milrinone