At what left ventricular ejection fraction (LVEF) are beta blockers contraindicated?

Beta Blockers Are Not Contraindicated Based on Ejection Fraction Alone

Beta blockers are not contraindicated at any specific left ventricular ejection fraction (LVEF) value, but rather should be used cautiously in patients with decompensated heart failure regardless of LVEF. 1

Beta Blocker Indications Based on LVEF

LVEF ≤40% (HFrEF)

• Beta blockers are strongly recommended (Class I recommendation) for all patients with LVEF ≤40% with heart failure or prior myocardial infarction, unless contraindicated 1
• Specific beta blockers with mortality benefit include carvedilol, metoprolol succinate, and bisoprolol 1
• Beta blockers should be used in combination with ACE inhibitors and aldosterone antagonists in patients with LVEF <40% to reduce mortality and hospitalization 1

LVEF 40-49% (HFmrEF)

• Beta blockers are reasonable for patients with LVEF 40-49% as they show similar mortality benefits as in HFrEF 2
• A recent individual patient-level analysis showed that for patients with LVEF 40-49%, beta blockers reduced cardiovascular death with an adjusted hazard ratio of 0.48 (95% CI 0.24-0.97) 2

LVEF ≥50% (HFpEF)

• Beta blockers may be considered for patients with preserved ejection fraction, though evidence for mortality benefit is less robust 3
• Recent research suggests potential increased risk of heart failure hospitalization in patients with LVEF >60% who are on beta blockers without other compelling indications 3

Contraindications and Cautions

Beta blockers are not contraindicated based on LVEF alone, but should be used with caution in the following situations:

• Decompensated heart failure with fluid overload (temporary contraindication until stabilized) 4
• Cardiogenic shock 1
• Severe bradycardia or heart block without pacemaker 1
• Severe reactive airway disease 5

Initiation and Titration

• Start at low doses in stable patients and gradually uptitrate to target doses 5
• For patients hospitalized with acute decompensated heart failure, beta blockers should be:
  • Continued if patient was previously on them and is hemodynamically stable 4
  • Temporarily reduced or held if patient has signs of poor perfusion or hypotension 4
  • Initiated prior to discharge once patient is euvolemic and hemodynamically stable 4

Special Considerations

• Beta blockers improve left ventricular function across different etiologies of heart failure, with slightly better response in non-ischemic cardiomyopathy (8.5 EF unit improvement vs 6.0 EF units in ischemic cardiomyopathy) 6
• Patients in atrial fibrillation may experience improvement in LVEF with beta blockers when baseline LVEF is <50%, but without the same mortality benefit seen in sinus rhythm 2
• The benefit of beta blockers appears to be independent of baseline LVEF in patients with sinus rhythm, except possibly in the small subgroup with LVEF ≥50% 2

Common Pitfalls

• Discontinuing beta blockers during heart failure hospitalization when they should be continued 4
• Failing to initiate beta blockers in eligible patients prior to hospital discharge 4
• Starting with too high a dose, leading to hemodynamic compromise 5
• Not allowing adequate time (2-3 months) for clinical benefits to become apparent 5

Remember that beta blockers are not contraindicated at any specific LVEF threshold, but rather their use should be guided by clinical status, heart rhythm, and hemodynamic stability.