Skip to content
evident
Original paper
1999LancetCardiology

MERIT-HF

Effect of metoprolol CR/XL in chronic heart failure: Metoprolol CR/XL Randomised Intervention Trial in Congestive Heart Failure

RCTHFrEF

On this page

Overview

Metoprolol succinate reduced mortality in stable symptomatic HFrEF.

Clinical takeaway

MERIT-HF helped establish evidence-based beta blockade as disease-modifying therapy in chronic HFrEF, not merely rate or blood-pressure control.

Key result

All-cause mortality was reduced by about 34% with metoprolol CR/XL.

Practice impact

Evidence-based beta blockers became a core pillar of HFrEF guideline-directed medical therapy.

Evidence

Study design

Randomized, double-blind, placebo-controlled trial stopped early for benefit.

Enrollment

3,991

Follow-up

Mean about 1 year.

Geography

Europe, United States

Clinical question

Does metoprolol CR/XL improve survival in patients with chronic symptomatic HFrEF?

Population

  • Patients with chronic heart failure, NYHA class II-IV symptoms, and reduced ejection fraction on standard therapy.

Intervention

Metoprolol CR/XL titrated to target dose.

Comparator

Placebo added to standard therapy.

Primary outcome

All-cause mortality.

Metoprolol CR/XL reduced all-cause mortality in chronic symptomatic HFrEF.

Relative risk / 0.66 / 95% CI 0.53-0.81 / p=0.0062

Key results

  • All-cause mortality: 145 vs 217 deaths (7.2% vs 11.0% per patient-year of follow-up); relative risk 0.66 (95% CI 0.53-0.81), a 34% reduction; p=0.00009, or p=0.0062 adjusted for interim analyses.
  • Sudden death: 79 vs 132 (RR 0.59; 95% CI 0.45-0.78; p=0.0002). Death from worsening heart failure: 30 vs 58 (RR 0.51; 95% CI 0.33-0.79; p=0.0023).
  • Hospitalizations for worsening heart failure were reduced.

Harms

  • Beta-blocker initiation can transiently worsen congestion if started during decompensated heart failure.
  • Bradycardia and hypotension require titration and monitoring.

Clinical Use

Practice impact

  • Established metoprolol succinate as one of the mortality-benefit beta blockers for HFrEF.

Applicability

  • Stable patients with chronic HFrEF who can tolerate careful beta-blocker initiation and titration.

Limitations

  • Pre-ARNI and pre-SGLT2 era.
  • Does not support starting beta blockers in unstable cardiogenic shock or severe acute decompensation.

Common misinterpretations

  • Do not treat all beta blockers as interchangeable for HFrEF mortality benefit; use evidence-based agents and formulations.

Related evidence

RALES - Same DiseasePARADIGM-HF - Later Trial

Citation

Effect of metoprolol CR/XL in chronic heart failure: Metoprolol CR/XL Randomised Intervention Trial in Congestive Heart Failure (MERIT-HF). Lancet. 1999;353(9169):2001-2007.

Metoprolol CR/XL once daily in addition to optimum standard therapy improved survival.