Levosimendan benefits critically ill patients with decompensated heart failure assessed with plasma B-type natriuretic peptide (BNP) and LVEF

Background

Levosimendan enhances cardiac contractility and ventricular diastolic function [1], acting as a calcium sensitiser, and producing vasodilation via vascular smooth muscle relaxation by ATP-dependent K⁺-channel activation. Although hemodynamic variables are often used to assess patients, less invasive measures are often preferred. Plasma levels of BNP correlate well with cardiac wall stress and changes in plasma BNP are associated with changes in morbidity and outcomes [2]. We investigated using echocardiographic-determined left ventricular ejection fraction (LVEF) and plasma BNP concentrations as surrogate endpoints to assess the efficacy of levosimendan in decompensated heart failure patients.

Methods

Informed consent was obtained to treat 14 critically ill patients, five with unstable hemodynamic conditions admitted to the ICU and nine with left ventricular ejection fraction (LVEF) < 25%; five with ischemic cardiomyopathy and four with dilated idiopathic cardiomyopathy (all NYHA class IV) were recruited. Levosimendan was infused as a 10-min bolus of 12 μg/kg, followed by 0.1 μg/kg per min for 24 hours. The left ventricular ejection fraction was determined echocardiographically by Simpson's method, before and after (< 1 hour) the infusion. Blood (4 ml) was collected before and immediately after infusion for plasma BNP measurements (Biosite^®, San Diego, CA, USA). P < 0.05 was regarded as significant.

Results

See Table 1.

Conclusion

In this initial study, we have confirmed the improvement in cardiac function after levosimendan infusion in patients with decompensated heart failure. We have demonstrated that levosimendan produces significant improvements in cardiac function as demonstrated by plasma BNP and echocardiographic LVEF measures. Changes in BNP level were more easily obtained and prone to less technical error than LVEF by echocardiography, which requires an experienced operator.

Table 1