Can metoprolol be administered to a patient receiving milrinone (phosphodiesterase inhibitor)?

From the Guidelines

Metoprolol should not be initiated in patients who are on milrinone due to the potential for worsening heart failure, hypotension, or bradycardia, as recommended by guidelines for the diagnosis and treatment of chronic heart failure 1.

Considerations for Beta-Blocker Use

When considering the use of beta-blockers like metoprolol in patients with heart failure, it is crucial to follow established guidelines. According to the European Heart Journal guidelines 1, patients should be on a background therapy with ACE inhibition if not contraindicated, and they should be in a relatively stable condition without the need for intravenous inotropic therapy.

Key Points for Management

• Patients on milrinone require careful assessment before initiating beta-blockers.
• The guidelines suggest starting with a very low dose of beta-blocker and titrating up to maintenance dosages if the patient is stable and not on intravenous inotropic support.
• Monitoring for signs of heart failure worsening, fluid retention, hypotension, and bradycardia is essential.
• If hypotension occurs, reducing the dose of vasodilators is recommended before adjusting the beta-blocker dose.

Specifics on Metoprolol and Milrinone Combination

While metoprolol and milrinone can be used together in certain clinical scenarios, this combination is not straightforward and requires careful consideration of the patient's hemodynamic status. The primary concern is the potential for additive negative effects on heart rate and contractility.

Clinical Decision Making

In real-life clinical practice, the decision to use metoprolol in a patient on milrinone should be made with caution, considering the potential risks and benefits. The patient's clinical status, the reason for milrinone use, and the potential for close monitoring are critical factors in this decision. Given the guidelines and the potential for adverse effects, initiating metoprolol in a patient on milrinone is generally not recommended without careful consideration and monitoring 1.

From the Research

Administration of Metoprolol with Milrinone

• The study 2 investigated the tolerability of beta-blockers in outpatients with refractory heart failure who were receiving continuous milrinone.
• The results showed that 12 patients received concomitant milrinone and beta-blockers, with 5 patients receiving metoprolol tartrate for 17.6 weeks.
• The dosages of beta-blockers were titrated, and the final daily dose of metoprolol was 42.5 mg (95% confidence interval 28.0-57.2).
• One patient discontinued metoprolol due to hypotension and/or worsening heart failure.
• The study suggests that metoprolol can be given to patients on milrinone, but the dosage should be titrated carefully to avoid adverse effects.

Comparison of Metoprolol with Other Beta-Blockers

• The study 3 compared the effects of metoprolol and carvedilol on survival after acute myocardial infarction.
• The results showed that the 3-year survival estimates were 88.2% and 83.5% for metoprolol and carvedilol, respectively.
• The study 4 investigated the influence of heart rate, blood pressure, and beta-blocker dose on outcome in patients with chronic heart failure.
• The results showed that achieving target beta-blocker dose was associated with a better outcome, and carvedilol was superior to metoprolol tartrate.
• The study 5 performed a meta-analysis of carvedilol versus beta 1 selective beta-blockers (atenolol, bisoprolol, metoprolol, and nebivolol).
• The results showed that carvedilol significantly reduced all-cause mortality compared to beta 1 selective beta-blockers in patients with systolic heart failure.

Considerations for Administration

• The study 2 suggests that metoprolol can be given to patients on milrinone, but the dosage should be titrated carefully to avoid adverse effects.
• The studies 3, 4, and 5 provide information on the comparison of metoprolol with other beta-blockers, but do not directly address the administration of metoprolol with milrinone.
• The study 6 discusses the use of calcium channel blockers, which is not directly relevant to the administration of metoprolol with milrinone.