When can home blood pressure medications, such as Angiotensin-Converting Enzyme (ACE) inhibitors or beta-blockers, be restarted after a myocardial infarction (MI)?

Restarting Home Blood Pressure Medications After Myocardial Infarction

Beta blockers and ACE inhibitors should be started within 24 hours of MI stabilization and continued indefinitely in most patients, with specific timing based on hemodynamic stability and risk factors. 1

Timing for Restarting Blood Pressure Medications

Beta Blockers

• Initial timing: Start beta blockers within a few days of MI if not initiated acutely 1
• For patients with hemodynamic stability: Begin treatment as soon as the patient's hemodynamic condition has stabilized 2
• For patients with moderate to severe LV failure: Use a gradual titration scheme 1
• Duration: Continue indefinitely for all patients recovering from MI unless contraindicated 1, 3

ACE Inhibitors/ARBs

• Initial timing: Start ACE inhibitors during the first day after MI after careful observation of hemodynamic and clinical status 4
• For high-risk patients: Begin early in stable high-risk patients (anterior MI, previous MI, heart failure, LVEF <0.40) 1
• Duration: Should be continued indefinitely in patients with:
  • LVEF ≤40%
  • Heart failure
  • Hypertension
  • Diabetes mellitus 1
• For lower-risk patients: May be discontinued at hospital discharge if no clinical symptoms or signs of LV dysfunction 4

Risk Stratification for Medication Management

High Priority for Indefinite Therapy

1. Patients with:
   • LVEF ≤40%
   • Heart failure symptoms
   • Anterior MI
   • Previous MI
   • Diabetes mellitus
   • Hypertension 1

Medication Selection Based on Patient Characteristics

• For all post-MI patients: Beta blockers (Class I, Level A recommendation) 3
• For patients with LV dysfunction: ACE inhibitors (Class I, Level A recommendation) 1
• For ACE inhibitor intolerant patients: ARBs are recommended (Class I, Level A) 1
• For patients with LVEF ≤40% and heart failure/diabetes: Consider aldosterone receptor blockers 1

Contraindications and Precautions

Beta Blocker Contraindications

• Signs of heart failure or risk for cardiogenic shock
• PR interval >0.24 seconds
• Second or third-degree heart block without pacemaker
• Severe bradycardia
• Active bronchospasm
• Systolic BP <120 mmHg with heart rate >110 bpm 3

ACE Inhibitor Contraindications

• History of angioedema
• Pregnancy
• Bilateral renal artery stenosis
• Hyperkalemia
• Severe renal dysfunction 5

Practical Approach to Restarting Home BP Medications

1. First 24 hours post-MI:

   • Temporarily discontinue or reduce premorbid antihypertensive medications 1
   • Assess hemodynamic stability

2. After hemodynamic stabilization (typically within 24 hours):

   • Begin beta blockers if no contraindications 2
   • Start ACE inhibitors in high-risk patients 1

3. Prior to discharge:

   • Reassess contraindications for those initially unable to receive medications 3
   • Ensure all eligible patients are prescribed appropriate therapy

4. Long-term management:

   • Continue beta blockers indefinitely in all patients 3
   • Continue ACE inhibitors indefinitely in high-risk patients 1
   • For patients with normal LV function, beta blockers should be continued for at least 3 years 3

Common Pitfalls to Avoid

1. Failure to reassess contraindications: Many patients with initial contraindications become eligible for therapy after 24 hours 3

2. Premature discontinuation: Benefits continue long-term, so therapy should be maintained unless not tolerated 3

3. Inadequate dosing: Focus on achieving recommended target doses rather than which specific agent is used 6

4. Overlooking combination therapy: Beta blockers, ACE inhibitors, and antiplatelet agents should be used together for optimal outcomes 7

5. Neglecting BP targets: Post-MI blood pressure should be controlled to <140/90 mmHg, and <130/80 mmHg in patients with diabetes or renal insufficiency 7