Differential Effects of Levosimendan and Dobutamine on Glomerular Filtration Rate in Patients With Heart Failure and Renal Impairment: A Randomized Double-Blind Controlled Trial

Background-The management of the cardiorenal syndrome in advanced heart failure is challenging, and the role of inotropic drugs has not been fully defined. Our aim was to compare the renal effects of levosimendan versus dobutamine in patients with heart failure and renal impairment. Methods and Results-In a randomized double-blind study, we assigned patients with chronic heart failure (left ventricular ejection fraction<40%) and impaired renal function (glomerular filtration rate <80 mL/min per 1.73 m(2)) to receive either levosimendan (loading dose 12 mu g/kg+0.1 mu g/kg per minute) or dobutamine (7.5 mu g/kg per minute) for 75 minutes. A pulmonary artery catheter was used for measurements of systemic hemodynamics, and a renal vein catheter was used to measure renal plasma flow by the infusion clearance technique for PAH (para-aminohippurate) corrected by renal extraction of PAH. Filtration fraction was measured by renal extraction of chromium ethylenediamine tetraacetic acid. A total of 32 patients completed the study. Following treatment, the levosimendan and dobutamine groups displayed similar increases in renal blood flow (22% and 26%, respectively) with no significant differences between groups. Glomerular filtration rate increased by 22% in the levosimendan group but remained unchanged in the dobutamine group (P=0.012). Filtration fraction was not affected by levosimendan but decreased by 17% with dobutamine (P=0.045). Conclusions-In patients with chronic heart failure and renal impairment, levosimendan increases glomerular filtration rate to a greater extent than dobutamine and thus may be the preferred inotropic agent for treating patients with the cardiorenal syndrome.