Which is better, Angiotensin-Converting Enzyme (ACE) inhibitors or Angiotensin Receptor Blockers (ARBs) for treating hypertension or heart failure?

ACE Inhibitors vs ARBs for Hypertension and Heart Failure

ACE inhibitors should be considered first-line therapy for hypertension and heart failure, with ARBs recommended as alternatives when ACE inhibitors are not tolerated due to side effects such as cough or angioedema. 1

Efficacy Comparison

• Both ACE inhibitors and ARBs effectively reduce blood pressure and have comparable effects on cardiovascular outcomes including mortality, myocardial infarction, heart failure, and stroke 2
• ACE inhibitors have been extensively studied and shown to reduce morbidity and mortality in patients with heart failure with reduced ejection fraction (HFrEF), with or without coronary artery disease 3
• ARBs produce similar hemodynamic, neurohormonal, and clinical effects to ACE inhibitors and are effective alternatives when ACE inhibitors cannot be tolerated 3, 1
• The American College of Cardiology recommends ACE inhibitors as first-line therapy for heart failure with reduced ejection fraction, post-myocardial infarction patients, and patients with diabetic nephropathy 1

Side Effect Profile Comparison

• ACE inhibitors commonly cause dry cough (in up to 20% of patients) due to their inhibition of kininase and increased levels of bradykinin 3, 1
• Angioedema occurs in <1% of patients taking ACE inhibitors but is more frequent in Black patients and women 3
• ARBs have a more favorable side effect profile with significantly lower incidence of cough and angioedema 1, 4
• Both medication classes require monitoring of renal function, serum potassium, and blood pressure, especially when initiating therapy 1

Specific Clinical Scenarios

Hypertension

• For initial treatment of hypertension, ACE inhibitors, ARBs, thiazide diuretics, and calcium channel blockers all have comparable effects on overall mortality and cardiovascular outcomes 3
• In patients with diabetes and hypertension, ACE inhibitors are recommended as first-line therapy 3
• For patients with albuminuria (UACR ≥30 mg/g), initial treatment should include an ACE inhibitor or ARB to reduce the risk of progressive kidney disease 3

Heart Failure

• In heart failure with reduced ejection fraction (HFrEF), ACE inhibitors are recommended first-line therapy to reduce morbidity and mortality 3
• ARBs are recommended for patients with HFrEF who are intolerant to ACE inhibitors due to cough or angioedema 3
• For patients with structural cardiac abnormalities or left ventricular hypertrophy, blood pressure should be controlled according to clinical practice guidelines to prevent symptomatic heart failure 3

Clinical Decision Algorithm

1. Initial therapy selection:

   • For most patients with hypertension or heart failure, start with an ACE inhibitor 1, 5
   • Consider ARB as initial therapy when the patient has a history of ACE inhibitor-induced cough or angioedema 1

2. Monitoring and follow-up:

   • Monitor renal function, serum potassium, and blood pressure when initiating either medication class 1
   • For patients treated with an ACE inhibitor, ARB, or diuretic, serum creatinine/eGFR and serum potassium levels should be monitored at least annually 3

3. Management of side effects:

   • If patient develops persistent dry cough on ACE inhibitor, switch to an ARB 1, 4
   • If angioedema occurs with an ACE inhibitor, discontinue immediately and switch to an ARB 3, 1

Important Clinical Considerations

• Combination therapy with both ACE inhibitor and ARB is generally not recommended due to increased adverse effects without significant additional benefit 1
• ARBs should not be initiated within 36 hours of discontinuing an ACE inhibitor due to the risk of overlapping effects 1
• Multiple-drug therapy is generally required to achieve blood pressure targets in patients with hypertension 3
• In resistant hypertension, consider adding a mineralocorticoid receptor antagonist to the regimen 3

Conclusion

While both ACE inhibitors and ARBs are effective for treating hypertension and heart failure, ACE inhibitors remain the first-line recommendation based on extensive clinical evidence. ARBs provide an excellent alternative for patients who cannot tolerate ACE inhibitors due to side effects, particularly cough or angioedema.