Levosimendan improves renal function in acute decompensated heart failure: possible underlying mechanisms

Aims The cardio-renal syndrome plays a critical role in acute heart failure (HF). Levosimendan, an inodilator drug, has a positive but controversial effect on kidney. Our aim was to evaluate its effects on both renal and systemic haemodynamic parameters as well as on renal function, explaining the possible mechanisms involved. Methods and results Patients with acute decompensated HF, moderate renal impairment, wedge pressure >20 mmHg and EF <40% were eligible. Twenty-one patients were randomized to infusion of levosimendan or placebo, on top of standard therapy. Systemic haemodynamic parameters (wedge and cardiac output) were evaluated at baseline and at 8, 16, 24, 48, and 72 h. An intravascular renal artery Doppler exam was performed at baseline, after levosimendan bolus, and 1 h thereafter. Renal blood flow, glomerular filtration rate (GFR), cystatin C, blood urea nitrogen (BUN), urinary output, sodium excretion, and plasma sodium were measured. The effect of levosimendan was beneficial and significantly different from placebo on several renal and cardiac parameters. Specifically, the levosimendan and placebo group exhibited significantly different changes over time in GFR (P = 0.037), renal blood flow (P = 0.037), and renal artery diameter (P = 0.033), with ensuing improvements in serum levels of BUN (P = 0.014), creatinine (P = 0.042), and cystatin C (P = 0.05). Concomitantly, levosimendan provided a significant increase in urine output up to 72 h (P = 0.02). These beneficial results on renal parameters were accompanied by similarly significant and favourable changes in cardiac index (P = 0.029) and PCWP (P < 0.001). Conclusion Levosimendan, in acute decompensated HF, has an immediate renoprotective effect, mediated by an increase in renal blood flow, due to a selective renal arterial and venous vasodilating action. Trial registration NCT00527059.