BACKGROUND: Treatment of acute heart failure frequently requires positive-inotropic stimulation. However, there is still no inotropic agent available, which combines a favourable haemodynamic profile with low expenditure for energy metabolism. Pyruvate exhibits positive inotropic effects in vitro and in patients with heart failure. The effect on myocardial energy metabolism however remains unclear, but is meaningful in light of a clinical application. AIMS AND METHODS: We investigated the influence of pyruvate on contractility and oxygen consumption in isolated isometric contracting rabbit myocardium compared to beta-adrenergic stimulation with isoproterenol. RESULTS: Pyruvate (30 mM) increased developed force from 18.7+/-4.1 to 50.8+/-12.1 mN/mm2 (n=10, p
