What is the recommended treatment for hypertension in patients with myocardial infarction?

Treatment of Hypertension in Myocardial Infarction

Beta-blockers and ACE inhibitors (or ARBs if ACE inhibitors are not tolerated) form the cornerstone of antihypertensive therapy in patients with myocardial infarction, with beta-blockers initiated within 24 hours in hemodynamically stable patients and ACE inhibitors started early, particularly in those with anterior MI, left ventricular dysfunction, heart failure, or diabetes. 1

Immediate Management (First 24 Hours)

Beta-Blockers: First-Line Therapy

• Initiate oral beta-blockers within the first 24 hours in hemodynamically stable patients without contraindications 1
• Beta-blockers are Class I recommendation (Level of Evidence A) for all post-MI patients, regardless of blood pressure status 1
• Contraindications to avoid: acute heart failure, hemodynamic instability, heart block (second or third-degree AV block), bradycardia, severe COPD, or cardiogenic shock 1, 2
• Preferred agents with proven mortality benefit: carvedilol, metoprolol, and bisoprolol 1
• Do NOT use intravenous beta-blockers initially if the patient shows any signs of hemodynamic instability—wait until stabilization is achieved 1

ACE Inhibitors: Essential Early Therapy

• Start ACE inhibitors early (within 24 hours) in all MI patients with hypertension, especially those with: 1, 3

  • Anterior myocardial infarction
  • Left ventricular ejection fraction <40%
  • Heart failure symptoms
  • Diabetes mellitus
  • Persistent hypertension despite other therapy

• ACE inhibitors reduce mortality by 22% in high-risk patients and are Class I recommendation (Level of Evidence A) 1

• If ACE inhibitors are not tolerated (typically due to cough), substitute an ARB, which has shown non-inferior outcomes 1

• Critical monitoring: Check serum creatinine and potassium within 1-2 weeks of initiation and avoid if baseline creatinine >2.5 mg/dL (men) or >2.0 mg/dL (women), or potassium >5.0 mEq/L 1

Blood Pressure Targets

• Target blood pressure: <130/80 mmHg in most post-MI patients 1
• In elderly patients (>80 years), a less aggressive target of <140/80 mmHg is acceptable 1
• Critical pitfall: Avoid lowering diastolic blood pressure below 60 mmHg, as this increases risk of coronary events due to reduced coronary perfusion pressure 1, 2
• Reduce blood pressure gradually—do not attempt rapid reduction, as this can worsen myocardial ischemia 2

Additional Antihypertensive Agents

Aldosterone Antagonists

• Add eplerenone or spironolactone if LVEF ≤40% and heart failure symptoms are present 1
• This provides a 15% mortality reduction at 16 months, with benefits seen as early as 30 days 1
• Mandatory exclusion criteria: serum creatinine >2.5 mg/dL (men) or >2.0 mg/dL (women), potassium >5.0 mEq/L, or estimated creatinine clearance <50 mL/min 1
• Monitor potassium levels closely due to serious hyperkalemia risk 1

Thiazide Diuretics

• Add a thiazide-type diuretic if blood pressure remains uncontrolled on beta-blocker and ACE inhibitor, or if heart failure with volume overload is present 1
• Diuretics are Class I recommendation (Level of Evidence A) for blood pressure control and heart failure management 1

Calcium Channel Blockers: Use With Caution

• Long-acting dihydropyridine CCBs (amlodipine, felodipine) may be added for refractory hypertension or ongoing ischemic symptoms unresponsive to beta-blockers 1
• Absolutely avoid: 1, 2
  • Rapid-release nifedipine (increases mortality)
  • Non-dihydropyridine CCBs (diltiazem, verapamil) in patients with heart failure or bradyarrhythmias
  • Any CCB in the acute STEMI setting

Agents to Avoid

Never use the following in acute MI with hypertension: 1, 2

• Sodium nitroprusside: Decreases regional coronary blood flow and increases myocardial damage 2
• Hydralazine (without nitrate): Associated with adverse outcomes 1, 2
• Immediate-release nifedipine: Causes severe hemodynamic instability and increased mortality 1, 2
• Alpha-blockers (doxazosin): Only use if all other agents fail at maximum doses 1
• Clonidine and moxonidine: Harmful in heart failure with reduced ejection fraction 1

Hypertensive Emergency in Acute MI

If severe hypertension (typically >180/120 mmHg) with ongoing ischemia: 2

• First-line intravenous agents: nitroglycerin, labetalol (if no contraindications), or esmolol 2
• Alternative options: nicardipine or urapidil 2
• Target: Reduce systolic BP to <140 mmHg gradually over hours, not minutes 2
• Add beta-blockade when using nitroglycerin to prevent reflex tachycardia that increases myocardial oxygen demand 2

Long-Term Management Algorithm

1. Continue beta-blocker indefinitely unless contraindications develop—this is standard of care for all post-MI patients 1
2. Continue ACE inhibitor (or ARB) indefinitely, particularly if LVEF <40%, hypertension, diabetes, or chronic kidney disease 1
3. Add aldosterone antagonist if LVEF ≤40% with heart failure symptoms 1
4. Add thiazide diuretic if BP remains ≥130/80 mmHg 1
5. Consider long-acting dihydropyridine CCB only if BP still uncontrolled after the above agents 1

Monitoring Requirements

• Check blood pressure at monthly intervals until target is achieved, then every 3-6 months 1
• Monitor serum potassium and creatinine at least 1-2 times per year, more frequently if on ACE inhibitor/ARB plus aldosterone antagonist 1
• Assess for orthostatic hypotension in elderly patients, especially octogenarians 1
• Watch for signs of myocardial ischemia if diastolic BP drops below 60 mmHg 1