Milrinone is a medication used to assist people who are experiencing sudden heart failure. Heart failure occurs when the heart is unable to pump blood throughout the rest of the body. Milrinone can be taken orally, injected or administered through an intravenous line (IV). It is the most widely used phosphodiesterase-III inhibitor, a type of drug that helps the heart contract while also relaxing and widening the blood vessels.
This medication typically is administered in a doctor's office or hospital setting, and it is not recommended to be used for a period longer than 48 hours. A patient on milrinone should receive lab tests to measure organ function, electrolyte level and blood pressure. He or she should also receive continuous monitoring through an electrocardiogram. The drug should not be used in patients who have severe blockage of the arteries or certain heart valve problems or who have recently experienced a heart attack. It should be used with extreme caution in children and avoided in women who are pregnant or breastfeeding.
Milrinone has been shown to increase a patient's chances of developing ventricular arrhythmia, or an irregular heartbeat, and tachycardia, a condition during which the heart beats too fast. Other severe side effects requiring immediate attention include severe allergic reaction, chest pain, severe dizziness, bronchospasm and low potassium levels. Common side effects include dizziness, headache, tremors and easy bruising or bleeding.
The use of milrinone has created controversy in the medical world. There has been shown to be an increased mortality rate among patients who receive high amounts of milrinone in its oral form. Milrinone is not typically recommended for long-term use among those with congestive heart failure. In IV form, milrinone can be combined with beta-blocker therapy, another treatment used to improve the heart's ability to pump. Such a combination has a synergistic effect and offers an option for people with advanced congestive heart failure who have no other treatment options.