Timing of inopressor initiation in patients with acute myocardial infarction complicated by cardiogenic shock

Abstract Introduction Inotropes and vasopressors (inopressors) are commonly used in the treatment of acute myocardial infarction complicated by cardiogenic shock (AMICS). The characteristics of patients subjected to early or late initiation of inopressors are not yet described, and the impact of timing on outcomes remains uncertain. Purpose This retrospective real-world data study aims to identify patient-, treatment-, and outcome characteristics of AMICS patients treated with early- or late initiated inopressors. Methods The Netherlands Heart Registration (NHR) prospectively records baseline, procedural, and outcome data for PCI patients. Between 2017-2021, additional retrospective data on CS patients were collected by fourteen Dutch hospitals. Patients were categorized based on the timing of inopressor initiation, either early (pre PCI) or solely late (at the cathlab or within 24 hours after PCI). Patients presenting with an out of hospital cardiac arrest were excluded. Missing data were imputed through multiple imputation (30x). Multivariable logistic regression analysis was performed to evaluate the association between the timing of inopressor initiation and 30-day mortality, adjusting for univariate significant confounders among variables known at admission. Results A total of 956 consecutive CS patients were included of whom 418 (43.7%) and 538 (57.3%) patients were subjected to early and late initiation of inopressors respectively. The most frequently used drug in both groups was noradrenaline. At baseline, patients in the early initiation group were younger (67.4 vs. 70.0 years, p <0.001), presented with a lower mean arterial pressure (MAP) (72.5 vs. 76.3, p = 0.048) and higher lactate (4.2 vs. 3.6, p = 0.012), and presented with a NSTEMI more often (36.0% vs. 14.2%, p <0.001). They also had a higher prevalence of previous myocardial infarction (33.9% vs. 22.9%, p <0.001) and previous CABG (14.3% vs. 6.2%, p <0.001). Moreover, 30-day mortality rates were higher in the early initiated group (48.6% vs. 37.6%, pLogrank <0.001). After multivariate adjustment for age, admission MAP and lactate, early inopressor initiation remained independently associated with 30-day mortality (OR 1.44, 95%-CI 1.08-1.98) compared to late initiation. Conclusion In this Dutch cohort of CS patients undergoing PCI, baseline- treatment- and outcome characteristics differed between patient categories receiving either early or late initiated inopressors. Patients who were subjected to early initiated inopressors were younger, presented with worse hemodynamics, had a more extensive cardiovascular medical history and higher 30-day mortality rates. The results of this study reemphasize the importance of identifying patients who benefit from inopressors.30-day mortality late vs. earlyTable patient characteristics