A 70-year-old man with HFrEF (EF 28%) remains NYHA class III despite optimized lisinopril and carvedilol plus chronic furosemide. His potassium is 4.2 mEq/L, creatinine 1.1 mg/dL, and eGFR 62. Which of the following additions to his regimen provides additional mortality benefit and completes the guideline-directed foundation of HFrEF therapy?

Question

Accepted Answer

✅ B. Spironolactone (Aldactone) 25 mg daily
In HFrEF, mineralocorticoid receptor antagonists (MRAs) such as spironolactone are a cornerstone of guideline-directed medical therapy. The RALES trial showed a 30% reduction in all-cause mortality when spironolactone was added to ACE inhibitor and loop diuretic therapy in NYHA III–IV HFrEF. Initiation requires potassium <5.0 and eGFR ≥30; this patient meets both criteria. Monitor K+ and creatinine at 1 week, 1 month, then periodically.

❌ A. Amlodipine (Norvasc) 5 mg daily
Amlodipine is neutral in HFrEF — it neither helps nor harms — and is not part of guideline-directed medical therapy for HFrEF. It may be used for refractory angina or hypertension not controlled by the HFrEF foundation, but it offers no mortality benefit in this setting.

❌ C. Digoxin (Lanoxin) 0.125 mg daily
Digoxin reduces HF hospitalizations but does not reduce mortality. It is a later-line agent for symptomatic relief in patients still symptomatic on optimized foundational therapy, not the next step before an MRA has been added.

❌ D. Hydralazine plus isosorbide dinitrate
This combination has mortality benefit specifically in self-identified Black patients with HFrEF (A-HeFT trial) or in those intolerant of ACE/ARB/ARNI. It is not the preferred next step in a patient already tolerating an ACE inhibitor who has not yet received an MRA.

:::important
HFrEF mortality-reducing foundation: ACE/ARB/ARNI + evidence-based beta-blocker + MRA + SGLT2 inhibitor. Spironolactone is the MRA step in the classic "triple therapy" mandate.
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