Drug Category: PDE inhibitor
Mechanism: Causes direct stimulation of myocardial contractility and acceleration of myocardial relaxation. In addition, it causes balanced arterial and venous dilation with a consequent fall in systemic and pulmonary vascular resistances, and left and right heart filling pressures. Cardiac output increases due to the stimulation of myocardial contractility and the decrease in left ventricular afterload.
As a result of this dual mechanism of action, the increase in cardiac output with milrinone is greater than that seen with nitroprusside at doses that produce comparable reductions of systemic resistance. Conversely, the arterial and venous dilator effects of milrinone are greater than those of dobutamine at doses that produce comparable increases in cardiac output.
- Jerrold H Levy, James M Bailey, G Michael Deeb Intravenous milrinone in cardiac surgery. Ann. Thorac. Surg.: 2002, 73(1);325-30