Background—We determined the short-term hemodynamic and clinical effects of levosimendan, a novel calcium-sensitizing agent, in patients with decompensated heart failure.

Methods and Results—One hundred forty-six patients with New York Heart Association functional class III or IV heart failure (mean left ventricular ejection fraction 21±1%) who had a pulmonary capillary wedge pressure ≥15 mm Hg and a cardiac index ≤2.5 L · min⁻¹ · m⁻² were enrolled in a multicenter, double-blind, placebo-controlled study and randomized 2:1 to intravenous infusion of levosimendan or placebo. Drug infusions were uptitrated over 4 hours from an initial infusion rate of 0.1 μg · kg⁻¹ · min⁻¹ to a maximum rate of 0.4 μg · kg⁻¹ · min⁻¹ and maintained at the maximal tolerated infusion rate for an additional 2 hours. Levosimendan caused dose-dependent increases in stroke volume and cardiac index beginning with the lowest infusion rate and achieving maximal increases in stroke volume and cardiac index of 28% and 39%, respectively. Heart rate increased modestly (8%) at the maximal infusion rate and was not increased at the 2 lowest infusion rates. Levosimendan caused dose-dependent decreases in pulmonary capillary wedge, right atrial, pulmonary arterial, and mean arterial pressures. Levosimendan appeared to improve dyspnea and fatigue, as assessed by the patient and physician, and was not associated with a significant increase in adverse events.

Conclusions—Levosimendan caused rapid dose-dependent improvement in hemodynamic function in patients with decompensated heart failure. These hemodynamic effects appeared to be accompanied by symptom improvement and were not associated with a significant increase in the number of adverse events. Levosimendan may be of value in the short-term management of patients with decompensated heart failure.