What is the recommended dosing for metoprolol (beta-blocker) in the management of Heart Failure (HF)?

Metoprolol Dosing for Heart Failure

Use metoprolol succinate extended-release (CR/XL) starting at 12.5-25 mg once daily and titrate every 2 weeks to a target dose of 200 mg once daily for all patients with heart failure with reduced ejection fraction (HFrEF). 1

Specific Formulation Required

• Only metoprolol succinate extended-release (CR/XL) is recommended for heart failure—metoprolol tartrate (immediate-release) has NOT demonstrated mortality reduction and should not be used 1
• The three evidence-based beta-blockers proven to reduce mortality in HFrEF are bisoprolol, carvedilol, and sustained-release metoprolol succinate 1

Initial Dosing Strategy

Starting dose:

• 12.5 mg once daily for NYHA class III-IV (more severe symptoms) 2, 3
• 25 mg once daily for NYHA class II (mild-moderate symptoms) 2, 3

Target dose: 200 mg once daily 1, 4

Titration Schedule

Double the dose every 2 weeks if the previous dose is well tolerated 4, 2:

• 12.5 mg → 25 mg → 50 mg → 100 mg → 200 mg once daily 4
• Titration period typically spans 6-8 weeks to reach target dose 3, 5

Mortality Benefits

The MERIT-HF trial demonstrated that metoprolol CR/XL at target dose achieved 6, 5:

• 34% reduction in all-cause mortality 2, 6
• 38% reduction in cardiovascular mortality 4
• 41% reduction in sudden death 4, 6
• 49% reduction in death from progressive heart failure 4
• 35% reduction in heart failure hospitalizations 4
• Number needed to treat: 27 patients for 1 year to prevent 1 death 4

When Target Dose Cannot Be Achieved

Aim for at least 50% of target dose (100 mg daily minimum) if full target cannot be tolerated—dose-response relationships exist for mortality benefit 1, 4. Even lower doses provide benefit: a post-hoc analysis showed patients on mean dose of 76 mg daily still achieved 38% mortality reduction compared to placebo 7. Some metoprolol is better than no metoprolol 4.

Monitoring During Titration

At each dose escalation, assess for 4:

• Heart rate: Target reduction but avoid <50 bpm with symptoms
• Blood pressure: Monitor for symptomatic hypotension
• Signs of congestion: Daily weights (increase diuretic if weight rises 1.5-2.0 kg over 2 days) 4
• Symptoms of worsening heart failure: Dyspnea, fatigue, peripheral edema

Managing Adverse Effects During Titration

For worsening congestion:

• First: Double the diuretic dose 1, 4
• Second: Halve the metoprolol dose only if increasing diuretic fails 1, 4

For marked fatigue or bradycardia:

• Halve the metoprolol dose 1, 4
• Review need for other heart rate-slowing drugs (digoxin, amiodarone, diltiazem, verapamil) 1

For heart rate <50 bpm with worsening symptoms:

• Halve the dose or stop if severe deterioration (rarely necessary) 1, 4
• Arrange ECG to exclude heart block 1

For symptomatic hypotension:

• First: Reduce/eliminate nitrates, calcium-channel blockers, other vasodilators 1, 4
• Second: Reduce diuretic dose if no signs of congestion 1, 4
• Last resort: Seek specialist advice before adjusting metoprolol 1

Critical Contraindications

Absolute contraindications 4:

• PR interval >0.24 seconds
• Second or third-degree heart block without pacemaker
• Active asthma or reactive airways disease
• Current or recent (within 4 weeks) heart failure exacerbation requiring hospitalization

Risk factors for cardiogenic shock (use caution) 4:

• Age >70 years
• Systolic BP <120 mmHg
• Heart rate >110 bpm or <60 bpm

Essential Clinical Pearls

• Never abruptly discontinue metoprolol—risk of rebound myocardial ischemia, infarction, and arrhythmias 1, 4
• Metoprolol CR/XL is effective in both ischemic and non-ischemic cardiomyopathy 2, 6
• At study conclusion in MERIT-HF, 64% of patients achieved the target dose of 200 mg daily 4
• Background ACE inhibitor or ARB therapy should be established before initiating beta-blocker 1
• Calcium-channel blockers (especially diltiazem and verapamil) should be discontinued due to negative inotropic effects 1