[Treatment of the low-output-syndrome with urapidil and dobutamine (author's transl)].

12 patients suffering from a low cardiac output syndrome following aorto-coronary bypass-graft surgery were treated with a combined therapy. The left ventricular afterload was decreased by Urapidil, and a low dose positive inotropic agent, dobutamine, was added. The right and left ventricular filling pressures were kept constant by simultaneous volume replacement. Decreasing the mean arterial pressure by Urapidil alone from 122 +/-5 mm Hg to 90 +/-3mm Hg raised the cardiac index from 1.8 1/m2 x min to 2.71 1/m2 x min. By addition od dobutamine 5 mu/kg BW x min the cardiac index was further increased to 3.4 1/m2 x min. The heart-rate was unchanged. The pressure-rate-product was decreased by 25% with Urapidil alone (p 7E 0.01) and was only slightly increased after addition of dobutamine. It is concluded that in the patients studied, reduction of the mechanical load on the heart by Urapidil in combination with positive inotropic stimulation of the myocardium by dobutamine improved cardiac haemodynamics without a significant detrimental effect on the myocardial oxygen balance.