Prognostic implication of Vasoactive Inotropic Score in adult patients with cardiogenic shock on veno-arterial extracorporeal membrane oxygenation.

BACKGROUND: Vasopressors and inotropes are crucial in managing cardiogenic shock (CS) as they enhance microcirculation in patients. Numerous studies have demonstrated the adverse outcomes associated with excessive use of vasoactive drugs and the vasoactive drug scoring system has emerged as a valuable prognostic tool, particularly in pediatric patients. This study aimed to examine the prognostic significance of the Vasoactive Inotropic Score (VIS) in adult patients with CS receiving veno-arterial extracorporeal membrane oxygenation (VA-ECMO) treatment.

METHODS: This retrospective multi-center study involved 2,453 adult patients who underwent VA-ECMO in China between 2015 and 2021. Among them, 1,742 adult patients with CS following VA-ECMO were finally included. The maximum VIS (VISmax) was determined by considering the highest doses of vasoactive and inotropic drugs administered within the first 6 hours before ECMO initiation. Based on the VISmax, patients were classified into two groups: 0-20 and >20. The primary outcome of this study was in-hospital mortality.

RESULTS: A total of 1,146 patients were included in the high VISmax group, while 596 patients were assigned to the low VISmax group. Overall, 882 (50.6%) patients experienced in-hospital mortality, with significantly higher rates observed among those with higher VISmax scores (41.4% for VIS ≤20 versus 68.3% for VIS >20; P<0.001). Similar trends were observed for 30-day mortality (40.7% for VIS ≤20 versus 64.9% for VIS >20; P<0.001). Multivariable regression analysis demonstrated that a VIS score exceeding 20 independently predicted in-hospital mortality [odds ratio (OR) 2.64; 95% confidence interval (CI): 2.10-3.33; P<0.001]. The receiver operating characteristic (ROC) analysis revealed that VIS had an area under the curve (AUC) of 0.65 (95% CI: 0.63-0.68; P<0.001) as a predictor of in-hospital mortality, with an optimal cutoff value of 20.1. Moreover, the VIS exhibited good predictive ability for in-hospital mortality in patients with acute myocarditis (AUC 0.70; 95% CI: 0.63-0.78; P<0.001).

CONCLUSIONS: Firstly, higher maximum level of VIS within the first 6 hours before ECMO initiation independently predicted poorer clinical outcomes in patients supported with ECMO for CS. Secondly, VIS exceeding 20 was significantly associated with increased risks of in-hospital mortality and 30-day mortality. Thirdly, when categorized by the cause of CS, a high VIS exhibited good predictive ability in patients with acute myocardial infarction, heart failure, and acute myocarditis.