The LION-HEART study was a multicentre, double-blind, randomised, parallel-group, placebo-controlled trial evaluating the efficacy and safety of intravenous administration of intermittent doses of levosimendan in outpatients with advanced chronic heart failure.
Sixty-nine patients from 12 centres were randomly assigned at a 2:1 ratio to levosimendan or placebo groups, receiving treatment by a 6-hour intravenous infusion (0.2 μg/kg/min without bolus) every 2 weeks for 12 weeks. The primary endpoint was the effect on serum concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) throughout the treatment period in comparison with placebo. Secondary endpoints included evaluation of safety, clinical events and health-related quality of life (HRQoL). The area under the curve (AUC, pg.day/mL) of the levels of NT-proBNP over time for patients who received levosimendan was significantly lower than for the placebo group (344 × 103 [95% Confidence Interval (CI) 283 × 103 -404 × 103 ] vs. 535 × 103 [443 × 103 -626 × 103 ], p = 0.003). In comparison with the placebo group, the patients on levosimendan experienced a reduction in the rate of heart failure hospitalisation (hazard ratio 0.25; 95% CI 0.11-0.56; P = 0.001). Patients on levosimendan were less likely to experience a clinically significant decline in HRQoL over time (P = 0.022). Adverse event rates were similar in the two treatment groups.
In this small pilot study, intermittent administration of levosimendan to ambulatory patients with advanced systolic heart failure reduced plasma concentrations of NT-proBNP, worsening of HRQoL and hospitalisation for heart failure. The efficacy and safety of this intervention should be confirmed in larger trials.

OBJECTIVE: The aim of this study was to determine whether intermittent ambulatory treatment with levosimendan would improve functional capacity, quality of life, and event-free survival in patients with advanced heart failure.
RESULTS: This was a prospective, randomized, double-blind, placebo-controlled, multicentre, parallel-group trial of pulsed infusions of levosimendan in 120 outpatients with advanced heart failure (EF ≤35%, NYHA class III or IV). The study was conducted at 11 centres in Austria, Greece, and Germany. Levosimendan (0.2 µg/kg/min) or placebo was administered for 6 h at 2-week intervals over 6 weeks, in addition to standard care therapy. The primary outcome was the proportion of patients with a ≥20% improvement in the 6 min walk test and a ≥15% score increase on the Kansas City Cardiomyopathy Questionnaire at the end of the 24-week study period. Secondary outcomes included event-free survival after 24 weeks. Analyses were performed on an intention-to-treat basis. The primary endpoint was reached in 19% of patients receiving levosimendan and 15.8% of patients receiving placebo (odds ratio 1.25; 95% confidence interval 0.44-3.59; P = 0.810). Cardiac death (four vs. one), heart transplants (two vs. one), and acute heart failure (14 vs. nine) were more frequent with placebo as compared with levosimendan. The incidence of side effects was comparable between groups.
CONCLUSIONS: Intermittent ambulatory treatment with levosimendan in patients with advanced heart failure did not improve significantly functional capacity or quality of life as compared with placebo. An adequately powered, event-driven trial is warranted to enlarge on our findings.
BACKGROUND: NCT01065194.