What are the recommended long‑term maintenance medications after a myocardial infarction?

Post-MI Maintenance Medications

Every patient discharged after myocardial infarction should receive aspirin 75–162 mg daily indefinitely, dual antiplatelet therapy for 12 months, high-intensity statin therapy targeting LDL-C <70 mg/dL, a beta-blocker, and an ACE inhibitor (or ARB if intolerant). 1

Core Medication Regimen (The "ABCDE" Approach)

Antiplatelet Therapy

Aspirin:

• Loading dose: 162–325 mg non-enteric-coated aspirin on day 1 2
• Maintenance dose: 75–162 mg daily indefinitely (81 mg preferred to minimize bleeding) 2, 1
• If true aspirin allergy exists: substitute clopidogrel 75 mg daily indefinitely 2, 1

Dual Antiplatelet Therapy (DAPT):

• Add a P2Y12 inhibitor to aspirin for exactly 12 months regardless of whether the patient received medical management, fibrinolysis, or PCI 2, 1
• Preferred agents: ticagrelor 90 mg twice daily or prasugrel 10 mg daily over clopidogrel 2
• Clopidogrel 75 mg daily is acceptable if ticagrelor or prasugrel are contraindicated 2, 1
• After 12 months: transition to aspirin monotherapy indefinitely 1

PCI-specific DAPT duration:

• Drug-eluting stent: minimum 12 months 2, 3
• Bare-metal stent: minimum 1 month (ideally 12 months) 2, 3
• Extended DAPT beyond 12 months may be reasonable in high-risk patients with low bleeding risk 1, 3

Critical pitfall: Prasugrel is contraindicated (Class III Harm) in patients with prior stroke or TIA 2

Beta-Blocker Therapy

• Initiate within the first 24 hours in hemodynamically stable patients 2, 1
• Continue indefinitely (minimum 3 years) 2, 1
• Particularly indicated when LVEF <40% or heart failure is present 2, 1
• Mortality benefit: 20–25% reduction in death and recurrent MI 1

Contraindications to avoid:

• Hypotension, acute heart failure, cardiogenic shock 2, 1
• High-grade AV block (PR >0.24 s, second- or third-degree block) 1
• Severe bradycardia (<50 bpm) or active asthma 2, 1

ACE Inhibitor / ARB Therapy

ACE inhibitor indications (Class I):

• Start within 24 hours for all post-MI patients, especially those with: 2, 1
  • Anterior MI
  • LVEF ≤40%
  • Heart failure
  • Diabetes
  • Hypertension
  • Chronic kidney disease
• Continue indefinitely 2, 1
• Begin with low dose (e.g., lisinopril 2.5–5 mg) and titrate upward 1

ARB substitution:

• Use ARB (valsartan or candesartan) if ACE inhibitor intolerance occurs (cough, angioedema) 2, 1
• ARB is indicated when LVEF <40% or clinical/radiological heart failure is present 2

Aldosterone antagonist:

• Add aldosterone blocker when LVEF ≤40% and symptomatic heart failure or diabetes is present 2, 1
• Required safety parameters: 2, 1
  • Creatinine ≤2.5 mg/dL (men) or ≤2.0 mg/dL (women)
  • Potassium ≤5.0 mEq/L

High-Intensity Statin Therapy

• Start as early as possible during index hospitalization 1
• Target LDL-C <70 mg/dL or ≥50% reduction from baseline 1
• Preferred agents: atorvastatin 40–80 mg or rosuvastatin 20–40 mg daily 1
• Continue indefinitely 1

Anticoagulation (When Specifically Indicated)

Warfarin is indicated ONLY for: 2, 1

• Atrial fibrillation or atrial flutter (target INR 2.0–3.0)
• Left ventricular thrombus (minimum 3 months, indefinitely if low bleeding risk)
• Extensive regional wall-motion abnormalities

Triple therapy (warfarin + DAPT):

• Target INR 2.0–2.5 (lower than usual) 2, 1
• Use low-dose aspirin 75–81 mg to reduce bleeding risk 2, 1
• Monitor closely for increased bleeding risk 2

Additional Evidence-Based Therapies

Proton Pump Inhibitor

• Co-prescribe with DAPT in patients at high risk for gastrointestinal bleeding 2, 1

Cardiac Rehabilitation

• Enroll all patients in structured cardiac rehabilitation program 2, 1
• Prescribe ≥30 minutes of aerobic activity daily (or 3–4 sessions per week) 2, 1

Blood Pressure Management

• Target <140/90 mmHg (or <130/80 mmHg with diabetes or chronic kidney disease) 2, 1
• Most patients require ≥2 antihypertensive agents (beta-blocker and ACE inhibitor provide foundation) 2, 1

Diabetes Management

• Target HbA1c <7% with lifestyle and pharmacologic therapy 2, 1

Influenza Vaccination

• Provide annual influenza vaccine to all patients with cardiovascular disease 1

Medications to AVOID (Class III)

Calcium-channel blockers:

• No mortality benefit for long-term secondary prevention 2, 1
• Short-acting dihydropyridines contraindicated for hypertension management post-MI 2

NSAIDs (except aspirin):

• Avoid during and after hospitalization due to increased risk of mortality, reinfarction, hypertension, heart failure, and myocardial rupture 1
• Ibuprofen specifically antagonizes aspirin's antiplatelet effect (Class III Harm) 1

Nitrates:

• Contraindicated in right ventricular infarction due to profound hypotension risk 1
• Exclude RV infarction using right-sided precordial leads (V3R, V4R) before administering 1

Peri-operative Management

Before CABG, discontinue: 2, 1

• Clopidogrel ≥5 days (preferably 7 days)
• Prasugrel ≥7 days
• Ticagrelor 5–7 days
• Exception: urgent revascularization where bleeding risk is acceptable

Summary Table: Core Post-MI Medications

Medication Class	Agent & Dose	Duration	Key Evidence
Aspirin	75–162 mg daily (81 mg preferred)	Indefinite	[2,1]
P2Y12 inhibitor	Ticagrelor 90 mg BID or prasugrel 10 mg daily or clopidogrel 75 mg daily	12 months, then stop	[2,1]
Beta-blocker	Metoprolol, carvedilol, or bisoprolol	Indefinite (minimum 3 years)	[2,1]
ACE inhibitor/ARB	Lisinopril, enalapril, ramipril, or valsartan/candesartan	Indefinite	[2,1]
High-intensity statin	Atorvastatin 40–80 mg or rosuvastatin 20–40 mg	Indefinite	[1]
Aldosterone antagonist	Spironolactone or eplerenone (if LVEF ≤40% + HF or DM)	Indefinite	[2,1]

Common pitfall: Patients often receive suboptimal doses or incomplete regimens—adherence to the full evidence-based regimen is associated with significantly lower mortality, especially in high-risk patients 4, 5. The benefit of complete guideline-directed therapy is greatest in those at highest risk, with a 36% relative risk reduction in major adverse cardiovascular events 4.