What is the recommended treatment for a patient with a reduced ejection fraction (EF) of 46%?

Treatment for Heart Failure with Mildly Reduced Ejection Fraction (EF 46%)

For a patient with an ejection fraction of 46%, SGLT2 inhibitors should be the primary treatment to decrease heart failure hospitalizations and cardiovascular mortality.

Classification and Understanding EF 46%

An ejection fraction of 46% falls into the category of Heart Failure with Mildly Reduced Ejection Fraction (HFmrEF), which is defined as LVEF 41-49% according to the 2022 AHA/ACC/HFSA guidelines 1. This classification is important as it guides specific treatment approaches.

Evidence-Based Treatment Algorithm for HFmrEF (EF 46%)

First-Line Therapy (Strongest Recommendation):

• SGLT2 inhibitors (Class 2a recommendation with Level B-R evidence) 1
  • Demonstrated significant benefit in decreasing HF hospitalizations and cardiovascular mortality
  • Based on EMPEROR-Preserved trial showing 21% reduction in primary endpoints 1

Additional Therapies to Consider (Class 2b recommendations):

• Beta-blockers (particularly evidence-based ones like carvedilol, metoprolol succinate, or bisoprolol)
• ARNi (Angiotensin Receptor-Neprilysin Inhibitor)
• ACEi (Angiotensin-Converting Enzyme inhibitors) or ARBs (Angiotensin Receptor Blockers)
• MRAs (Mineralocorticoid Receptor Antagonists)

Implementation Strategy

1. Start with SGLT2 inhibitor as the cornerstone therapy
2. Add additional agents from the above classes based on:
   • Blood pressure (if hypertensive, prioritize ACEi/ARB/ARNi)
   • Presence of other comorbidities (diabetes, renal function)
   • Tolerance to therapy
   • Prior history of HF hospitalization

Important Clinical Considerations

• Medication titration: Aim for the highest tolerated doses of each medication class
• Regular monitoring: Assess renal function, electrolytes, and blood pressure
• Repeat LVEF assessment: Important to track trajectory of cardiac function
• Continue therapy even if symptoms improve: The guidelines emphasize that patients who improve their LVEF should continue their HF treatment 1

Special Considerations

• If the patient previously had HFrEF (EF <40%) and improved to current EF of 46%, they would be classified as having HFimpEF (Heart Failure with improved Ejection Fraction) and should continue full HFrEF therapy 1
• If this is a new diagnosis with EF 46%, follow the HFmrEF treatment approach outlined above

Common Pitfalls to Avoid

1. Undertreating HFmrEF: Studies show significant gaps in medication use and dosing in HF patients 2, 3
2. Failure to titrate medications: Only a small percentage of patients receive target doses of guideline-directed medical therapy 3
3. Discontinuing therapy when symptoms improve: Continued therapy is essential even if LVEF improves 1
4. Not reassessing LVEF: Regular monitoring of EF trajectory is important for treatment adjustments

Economic Value Considerations

The 2022 guidelines note that SGLT2i therapy provides intermediate economic value in patients with symptomatic chronic HF 1, supporting its use as first-line therapy.

By following this evidence-based approach to treating a patient with HFmrEF (EF 46%), you can optimize outcomes related to morbidity, mortality, and quality of life.