Haemodynamic dose-efficacy of levosimendan in healthy volunteers

Levosimendan is a new calcium-sensitiser intended for the treatment of congestive heart failure. The results of preclinical studies indicate it has positive inotropic and vasodilator effects. In the open study reported here up to 5 mg levosimendan and vehicle were administered to 8 healthy male volunteers at one- to 2-week intervals. Efficacy was evaluated using M-mode echocardiography, and by measuring systolic time intervals, recording ECG and measuring blood pressure. For almost all haemodynamic parameters except heart rate (HR) the maximum effect was seen 10 or 20 min after drug infusion. Effects 10 min after infusion of drug and vehicle were compared. HR was significantly increased 10 min only after infusion of 5 mg: significant increases were seen 60 min after infusions of 2, 3 and 5 mg (4, 8 and 17 beats.min-1, respectively). Diastolic blood pressure was significantly lower after doses of 1 mg or more. The decrease after 5 mg was 17 mmHg. Systolic blood pressure tended to increase. Fractional shortening (FS) and ejection fraction (EF) increased significantly after doses of 1 mg and higher. EF 10 min after infusion of vehicle was 54%. It increased to 73% after 5 mg. Decreases in electromechanical systole (QS2i) 10 min after 2, 3 and 5 mg were significant. There were no clinically significant adverse events or changes in laboratory safety values. The changes in QS2i, FS, EF and blood pressure indicate that levosimendan has positive inotropic and vasodilator effects in healthy subjects.