Although most patients in Europe with systolic heart failure (SHF) are treated with I(2)-blocking agents at doses significantly lower than the recommended dose, there is limited information available regarding the hemodynamic effects of dobutamine in this patient population. Therefore, a study was carried out in patients (n=31) admitted to the University Hospital, Larissa, Greece with an acute exacerbation of chronic SHF (25 men and 6 women, mean age 58 years, range 32 â 80 years, left ventricular (LV) ejection fraction <or= 0.35) and a systolic blood pressure between 85 and 110 mmHg. All patients underwent a complete echocardiographic/ Doppler examination before and immediately after a 24-hour intravenous dobutamine infusion (2.5-10 microg/kg/min). Of the patients admitted to the study, 22 (71%) had been treated by practicing physicians and the mean carvedilol dose at admission was 16+/-9 mg daily (6.25-50 mg daily). Dobutamine was associated with a small increase in LV ejection fraction (from 26.3+/-4.3% to 27.8+/-4.3%, p=0.005), a non-significant increase in heart rate (71.4+/-11 vs. 68+/-18 beats/min, p=0.19) and cardiac output (3.52+/-1 l/min vs. 3.74+/-1.06 l/min, p=0.14) and a significant decrease in the E-wave deceleration time (146.2+/-65 msec vs. 142.6+/-58.3 msec, p=0.04). Thus, in patients with SHF, treated with low doses of carvedilol, the favorable hemodynamic effects of dobutamine are blunted and alternative inotropic agents should be used.