From the Guidelines
Milrinone should be used with caution in patients with acute decompensated heart failure and cardiogenic shock, with a typical dosing of 50 mcg/kg loading dose administered intravenously over 10 minutes, followed by a continuous infusion of 0.375-0.75 mcg/kg/minute, as recommended by the most recent study 1.
Key Considerations
- The dose should be adjusted based on hemodynamic response and reduced in patients with renal impairment.
- Milrinone works by increasing cardiac contractility and causing vasodilation, which improves cardiac output without significantly increasing myocardial oxygen demand.
- Unlike catecholamines, it doesn't act through beta-adrenergic receptors, making it useful when beta-receptor downregulation occurs in chronic heart failure.
- Common side effects include hypotension, arrhythmias, and headache.
- Continuous hemodynamic monitoring is essential during administration, and patients should be monitored for electrolyte abnormalities, particularly potassium and magnesium, as deficiencies can potentiate arrhythmias.
Important Precautions
- Milrinone should be used cautiously in patients with severe aortic or pulmonary valvular disease and avoided in those with severe obstructive coronary artery disease.
- The use of milrinone may increase the risk of atrial fibrillation, as reported in a recent study 1.
- The optimal use of inotropes or vasopressors in the perioperative period of cardiac surgery is still controversial and needs further large multinational studies, as noted in a clinical review 1.
From the FDA Drug Label
INDICATIONS AND USAGE Milrinone Lactate Injection is indicated for the short-term intravenous treatment of patients with acute decompensated heart failure. The main use of Milrinone is for the short-term intravenous treatment of patients with acute decompensated heart failure 2.
- Key points:
- Indication: Acute decompensated heart failure
- Administration: Short-term intravenous treatment
- Monitoring: Close observation with electrocardiographic equipment is required.
From the Research
Milrinone Overview
- Milrinone is a valuable agent in treating end-stage heart failure patients who do not respond to optimal medical therapy 3
- It can be used as a home infusion therapy or a bridge to cardiac transplant 3
- Milrinone is also employed in the treatment of acute decompensated heart failure, particularly in patients with significant pulmonary venous hypertension 4
Clinical Use and Efficacy
- The choice of milrinone versus other inotropes, such as dobutamine, depends on patient characteristics, including the presence of ischemia, degree of congestion, and renal function 4
- Studies have compared the efficacy of milrinone and dobutamine in acute decompensated heart failure, with some indicating a marginal benefit of milrinone over dobutamine in terms of mortality 5
- However, other studies have found no significant differences in outcomes between milrinone and dobutamine, except for longer intensive care unit length of stay in the milrinone group 6
Safety and Adverse Effects
- Concerns about milrinone's adverse effects, such as increased risk of arrhythmias and hypotension, often limit its use in clinical practice 3
- Milrinone is primarily cleared by renal excretion, making it less suitable for patients with acute renal failure or end-stage renal disease 3
- Studies have reported varying rates of adverse effects, including arrhythmias, symptomatic hypotension, and acute kidney injury, with no significant differences between milrinone and dobutamine in most cases 5, 6
Comparison with Other Therapies
- Nesiritide has been compared to milrinone and dobutamine in the treatment of acute decompensated heart failure, with some studies suggesting a lower in-hospital mortality rate and shorter length of stay with nesiritide 7
- However, these findings need to be validated by randomized controlled trials to confirm the optimal choice of therapy for acute decompensated heart failure 7