II. Indications
- Refractory NYHA Class 3 to 4 Systolic Dysfunction
III. Mechanism
- Phosphodiesterase (PDE) inhibitor Type 3
- Blocks breakdown of cyclic Adenosine monophosphate (cAMP) in Myocardium and vascular Smooth Muscle
- Sustains Catecholamine activity (even when B-adrenergic Antagonists are present)
- Ineffective when cellular cAMP is depleted
- Activity
- Strong inotropy with increased contractility
- Derived from Amrinone, which is 20-30 times less potent than Milrinone
- Increases Stroke Volume and ejection fraction
- Increases sinus rate
- Decreases Afterload by dilating arterioles
- Decreases Peripheral Vascular Resistance
- Strong inotropy with increased contractility
IV. Dosing: Adults
- Load: 50 mcg/kg IV infused over 10 minutes
- Maintenance
V. Dosing: Children
- Load: 50 mcg/kg IV infused over 10 minutes
- Maintenance: 0.5 to 1 mcg/kg/min titrated to effect
VI. Pharmacokinetics
- Half life: 1.5 hours
VII. Adverse Effects
- Hypotension risk (avoid in Hypovolemia)
- Ventricular Arrhythmias
- Monitor on telemetry during infusion
VIII. Safety
- Pregnancy Category C
- Unknown safety in Lactation
IX. Resources
- Milrinone Injection Solution
X. References
- Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 74-5
- Hamilton (2020) Tarascon Pocket Pharmacopoeia