ACE Inhibitor is the Most Appropriate Pharmacotherapy for This Patient
An angiotensin-converting enzyme (ACE) inhibitor is the most appropriate pharmacotherapy for this 72-year-old man with heart failure with reduced ejection fraction (HFrEF) who already takes a beta-blocker. 1
Patient Assessment
This patient presents with:
- 72 years of age
- History of myocardial infarction 2 years ago
- Reduced ejection fraction (35%)
- Mild to moderate exertional dyspnea
- S4 gallop on cardiac examination
- Currently on beta-blocker therapy only
- No peripheral edema
- Clear lungs
- Normal laboratory studies
Evidence-Based Treatment Algorithm
Step 1: Confirm Diagnosis
The patient has HFrEF (EF 35%) with NYHA Class II symptoms (mild symptoms with ordinary activity). The S4 gallop is consistent with diastolic dysfunction often seen in HFrEF.
Step 2: Evaluate Current Therapy
The patient is currently only on a beta-blocker, which is appropriate but insufficient as monotherapy for HFrEF.
Step 3: Add Guideline-Directed Medical Therapy
According to the 2016 ESC guidelines, the recommended pharmacological treatment for HFrEF includes:
ACE inhibitor + Beta-blocker as foundation therapy
- "An ACE-I is recommended, in addition to a beta-blocker, for symptomatic patients with HFrEF to reduce the risk of HF hospitalization and death." (Class I, Level A recommendation) 1
Add MRA if symptoms persist
- "An MRA is recommended for patients with HFrEF who remain symptomatic despite treatment with an ACE-I and a beta-blocker." (Class I, Level A) 1
Why ACE Inhibitor is the Best Choice
Evidence-based mortality benefit: ACE inhibitors are specifically recommended for patients with asymptomatic LV systolic dysfunction and a history of myocardial infarction to prevent or delay the onset of HF and prolong life (Class I, Level A) 1
Established combination with beta-blockers: The combination of an ACE inhibitor and beta-blocker is the cornerstone of HFrEF treatment 1
Post-MI benefit: In patients with a history of MI and reduced EF, ACE inhibitors have shown significant mortality reduction 2
Why Other Options Are Not Appropriate
Alpha-adrenergic blocking agent: Not indicated for HFrEF and may cause hypotension without mortality benefit in this setting.
Angiotensin-receptor blocker (ARB): Only recommended as an alternative when ACE inhibitors are not tolerated 1
Nitrates: Not indicated as first-line therapy for chronic HFrEF without specific indications like angina.
Thiazide diuretic: While diuretics help with symptom control in patients with fluid overload, this patient has no peripheral edema or pulmonary congestion, making diuretics less appropriate as the next agent 1
Potential Pitfalls and Considerations
Monitor renal function and potassium: After initiating ACE inhibitor therapy, renal function and electrolytes should be checked within 1-2 weeks.
Start at low dose and titrate: Begin with a low dose (e.g., enalapril 2.5 mg BID or lisinopril 2.5-5 mg daily) and gradually increase to target doses shown to reduce mortality in clinical trials 1
Watch for hypotension: Especially in elderly patients, monitor blood pressure closely during initiation and titration.
Angioedema risk: Though rare, be vigilant for this potentially serious side effect.
Future Treatment Considerations
If the patient remains symptomatic despite optimal doses of beta-blocker and ACE inhibitor:
Add a mineralocorticoid receptor antagonist (MRA) like spironolactone or eplerenone 1
Consider switching from ACE inhibitor to sacubitril/valsartan (ARNI) if symptoms persist 1
Evaluate for ICD placement given the patient's EF ≤35% and history of MI 1
In summary, an ACE inhibitor is clearly the most appropriate next pharmacotherapy for this patient with HFrEF who is already on a beta-blocker, based on strong evidence for mortality reduction and guideline recommendations.