Clinical trials investigating traditional inotropic agents in patients with heart failure demonstrated an increased mortality rate (odds ratio 1.50; IC=0.51-3.92), high incidence of discontinuation of infusion therapy (odds ratio 0.46; IC=0.083-2.29) due to major side effects and, most of all, a limited clinical benefit (odds ratio 0.75; IC=1.42-0.08). On this background a new class of inotropic drugs, the calcium-sensitisers, have been developed. The safety and efficacy of levosimendan (Simdax) has been recently demonstrated in trials (LIDO e RUSSLAN) in patients with heart failure due to ischemic and not ischemic disease. Twenty-six patients with decompensated heart failure of different etiology have been treated with 24 hour infusion of levosimendan. In this experience the levosimendan improved the clinical status and the left ventricular ejection fraction.