Tholén M, et al. - Acute kidney injury (AKI) after cardiac surgery occurs frequently and has serious impacts, and current strategies to manage AKI have proven ineffective. Researchers herein aimed at testing their hypothesis that levosimendan through its specific effects on renal vasculature, a preferential vasodilating effect on preglomerular resistance vessels, could improve renal function in AKI-patients with who did not have clinical indication for inotropic support. They conducted a single-center, double-blind, randomized controlled study including adult patients with postoperative AKI within 2 days after cardiac surgery, who were hemodynamically stable with a central venous oxygen saturation (ScvO2) ≥ 60% without inotropic support. Twenty-nine patients completed the study. Findings revealed that levosimendan through renal vasodilatation resulted in an increase in renal blood flow; however, it had no significant impact on GFR, while filtration fraction decreased. These findings indicate that in AKI, levosimendan causes a dilation of both pre- and post glomerular resistance vessels.