What changes should be made to the patient's current heart failure medication regimen?

Optimizing Heart Failure Medication Regimen

The patient's heart failure medication regimen requires significant optimization, including switching from metoprolol tartrate to metoprolol succinate, adding an ACEI/ARB, adding an SGLT2 inhibitor, and adding a mineralocorticoid receptor antagonist (MRA) to reduce mortality and hospitalizations. 1

Current Regimen Analysis

The patient is currently on:

• Metoprolol tartrate 25 mg BID
• Torsemide 60 mg daily
• Isosorbide dinitrate 10 mg BID
• Amiodarone 400 mg daily

Key Issues with Current Regimen:

1. Beta-blocker: Using metoprolol tartrate instead of the evidence-based metoprolol succinate
2. Missing foundational therapies: No ACEI/ARB, no SGLT2 inhibitor, no MRA
3. Suboptimal dosing: Current beta-blocker dose is below target

Recommended Medication Changes

1. Beta-blocker Optimization

• Change metoprolol tartrate 25 mg BID to metoprolol succinate 50 mg daily
• Metoprolol succinate (extended-release) is the evidence-based beta-blocker studied in heart failure trials with proven mortality benefit 1
• Target dose is 200 mg daily, with gradual uptitration 1
• Metoprolol tartrate should not be used in preference to evidence-based beta-blockers in heart failure 1

2. Add ACEI

• Add lisinopril 5 mg daily
• Starting dose for heart failure is 5 mg daily when used with diuretics 2
• Target dose is 20-40 mg daily 1, 3
• Monitor for hypotension, especially with concurrent nitrate therapy

3. Add SGLT2 Inhibitor

• Add empagliflozin 10 mg daily or dapagliflozin 10 mg daily
• SGLT2 inhibitors reduce mortality by 17% with an NNT of 22 over 36 months 1
• No dose titration needed; start and maintain at 10 mg daily

4. Add Mineralocorticoid Receptor Antagonist

• Add spironolactone 25 mg daily
• MRAs provide the greatest mortality benefit with NNT of 6 over 36 months 1
• Monitor potassium and renal function after 4-6 days 1

5. Evaluate Isosorbide Dinitrate Dosing

• Current dose (10 mg BID) is below the target dose for heart failure
• Consider increasing to 40 mg isosorbide dinitrate TID if tolerated 1
• Particularly beneficial in African American patients 1

6. Review Amiodarone

• Evaluate continued need for amiodarone 400 mg daily
• Consider dose reduction if maintained for rhythm control
• Monitor for thyroid, liver, and pulmonary toxicity

Plan for Next Visit

1. Assess Tolerability:

   • Check blood pressure, heart rate, and symptoms
   • Review electrolytes, renal function, and potassium levels

2. Medication Uptitration Plan:

   • If metoprolol succinate 50 mg daily is tolerated, increase to 100 mg daily
   • If lisinopril 5 mg daily is tolerated, increase to 10 mg daily
   • Maintain SGLT2 inhibitor at 10 mg daily (no titration needed)

3. Monitor for Adverse Effects:

   • Hypotension (particularly with combined ACEI and nitrates)
   • Hyperkalemia (with addition of MRA)
   • Worsening renal function
   • Fluid status and congestion

4. Long-term Goal:

   • Achieve target doses of all four foundational therapies:
     • Metoprolol succinate 200 mg daily
     • ACEI at target dose (lisinopril 20-40 mg)
     • SGLT2 inhibitor 10 mg daily
     • MRA 25-50 mg daily

Important Considerations

• Sex-specific dosing: Some evidence suggests women may achieve optimal outcomes at lower doses (approximately 50% of target doses) of beta-blockers and ACEIs 1

• Common pitfalls to avoid:

  • Failure to switch from non-evidence-based to evidence-based beta-blockers
  • Reluctance to initiate multiple guideline-directed therapies simultaneously
  • Inadequate uptitration of medications to target doses
  • Not adding an SGLT2 inhibitor due to absence of diabetes (benefit is independent of diabetes status)

• Monitoring requirements:

  • Check electrolytes and renal function 1-2 weeks after initiation of ACEI and MRA
  • Monitor weight daily to assess fluid status
  • If hypotension occurs, consider reducing diuretic dose before reducing disease-modifying therapies

The MERIT-HF trial demonstrated a 34% reduction in all-cause mortality with metoprolol succinate, highlighting the importance of using this specific formulation rather than metoprolol tartrate 4. Unfortunately, real-world data shows that most patients receive less than half the target doses of beta-blockers proven effective in clinical trials 5.