[Myocardial contractility during limited haemodilution (author's transl)]

The direct cardiac effects of limited isovolaemic haemodilution by low molecular dextran was investigated in the cat heart-lung preparation. This type of preparation does not allow evaluation of the significance of nervous or humoral influences. All haemodynamic and contractile parameters remain unchanged as does myocardial adaptability to acute changes in pressure or volume load. However, cardiac function curves and the estimation of contractility by means of force-velocity-relations reveal a slight increase of the inotropic state.