Dobutamine: A New Agent for the Management of Cardiac Decompensation

Dobutamine is a new inotropic agent being promoted for short-term, parenteral treatment of adults with “cardiac decompensation due to depressed contractility resulting either from organic heart disease or from cardiac surgical procedures.” Pharmacologically, it most resembles the effects of low-dose epinephrine, but with fewer beta-2 adrenergic effects. The reported advantage of dobutamine over other currently available inotropic catecholamines is that, with dobutamine, cardiac output is increased with less concurrent heart rate increase or arrhythmia potential. Dobutamine has been compared to three other drugs in congestive heart failure: isoproterenol, nitroprusside, and dopamine. Isoproterenol appears to produce a greater increase in heart rate than dobutamine; nitroprusside produces a greater decrease in capillary wedge pressure and mean arterial pressure than dobutamine, but produces the same increase in cardiac index. Except for differences in effects on pulmonary capillary wedge pressure, dobutamine and dopamine demonstrate parallel effects up to a dose of 5 μg/kg/min of dopamine. Above this dose, changes in heart rate, arrhythmias (PVCs), and peripheral resistance differentiate the two drugs. Based on available data, dobutamine appears to have hemodynamic advantages over dopamine in congestive heart failure, but these advantages are not seen in postsurgical cardiac depression. At this time, dobutamine cannot be recommended over other agents for use in the acute MI patient.