Phosphodiesterase III inhibitors constitute a new therapeutic group for congestive cardiac failure. They inhibit the degradation of cyclic adenosine monophosphate and increase the intracellular calcium. They have a double inotropic and vasodilator haemodynamics occurs without any increase in the myocardial effect. The improvement in the consumption of oxygen. The beneficial haemodynamic effect seems to last over a medium period of time, but the survival in the long term treatment is not yet known.