Both levosimendan and dobutamine treatments result in significant reduction of NT-proBNP levels, but levosimendan has better and prolonged neurohormonal effects than dobutamine

Serum concentrations of levosimendan and its metabolites OR-1855 and OR-1896 in cardiac surgery patients with cardiopulmonary bypass

Background

The inotropic drug levosimendan is often used as an individualized therapeutic approach perioperatively in cardiac surgery patients with cardiopulmonary bypass (CPB). Data regarding serum concentrations of levosimendan and its metabolites within this context is lacking.

Methods

In this retrospective descriptive proof-of-concept study, total serum concentrations (TSC) and unbound fractions (UF) of levosimendan and its metabolites OR-1896 and OR-1855 in cardiac surgery patients with CPB were measured using LC-ESI-MS/MS. Simulation of expected levosimendan TSC was performed using Pharkin 4.0. Serum NT-proBNP was assessed with ELISA.

Results

After levosimendan infusion (1.25 mg or 2.5 mg, respectively) after anaesthesia induction, a median TSC of 1.9 ng/ml and 10.4 ng/ml was determined in samples taken directly after surgery (T1). Median TSC of 7.6 ng/ml and 22.0 ng/ml, respectively, were simulated at T1. Whereas 1.1 ng/ml and 1.6 ng/ml TSC of OR-1896, respectively, was quantified the day after surgery (T2), TSC of the intermediate metabolite OR-1855 was mostly below the lower limit of quantification (LLOQ). The UF was 0.5% and 1.1% for levosimendan and 64.1% and 52.1% for OR-1896, respectively, with over half the samples being below LLOQ. NT-proBNP concentrations before surgery and T2 did not differ.

Discussion

The low TSC, UF and unchanged NT-proBNP levels in combination with high variation of serum levels between patients suggest a need for optimized dosing regimen of levosimendan combined with therapeutic drug monitoring for such an individualized approach. In addition, the differences between the measured and estimated concentrations may suggest a possible influence of CPB on levosimendan serum concentrations.

Exploratory Assessment of Levosimendan in Infants With Congenital Diaphragmatic Hernia

OBJECTIVES

Infants with congenital diaphragmatic hernia frequently suffer from cardiac dysfunction and pulmonary hypertension during the postnatal course. With the use of the inodilator levosimendan, a therapeutic approach is available in situations with catecholamine-refractory low-cardiac-output failure and severe pulmonary hypertension.

DESIGN

Retrospective single-center cohort study.

SETTING

University-based, tertiary-care children's hospital neonatal ICU.

PATIENTS

Cohort of 24 infants with congenital diaphragmatic hernia and levosimendan therapy, without underlying major cardiac defect, treated at the University Children´s Hospital Bonn, Germany, between January 2017 and December 2018.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Twenty-four infants with congenital diaphragmatic hernia were treated with levosimendan (41% of hospitalized congenital diaphragmatic hernia infants in the study period). In 88%, the congenital diaphragmatic hernia was left-sided. The median observed-to-expected lung-to-head ratio was 36%. About 60% of the infants were supported with venovenous extracorporeal membrane oxygenation and the mortality was 38% (9/24 infants). Levosimendan administration was associated with improvement of pulmonary hypertension severity (p = 0.013 and p = 0.000) and right ventricular dysfunction (p = 0.011 and p = 0.000) at 24 hours and 7 days after treatment. Similarly, the prevalence of left ventricular dysfunction decreased from 50% at baseline to 10% after 7 days (p = 0.026). A significant reduction in the peak inspiratory pressure was observed after drug application (p = 0.038) and a significant decrease of the Vasoactive-Inotropic Score was apparent (p = 0.022). A relevant arterial hypotension as a drug-related adverse event occurred in one patient.

CONCLUSIONS

This is the first study exploring clinical and hemodynamic changes after levosimendan treatment in a cohort of infants with congenital diaphragmatic hernia. An association of levosimendan application and an improvement in pulmonary hypertension, right ventricular, and left ventricular dysfunction were observed within 7 days after drug infusion. However, due to the retrospective design of this study, the results should be interpreted carefully.