What is the recommended management for a patient who suffers a myocardial infarction during the peri‑operative period (from intra‑operative time to 30 days post‑surgery)?

Management of Perioperative Myocardial Infarction

Immediate Recognition and Diagnosis

Patients who develop myocardial infarction during the perioperative period require immediate identification of the MI mechanism (Type 1 vs Type 2) to guide management, with Type 1 MI requiring consideration for invasive coronary angiography and Type 2 MI requiring correction of the underlying supply-demand mismatch. 1

Diagnostic Approach

• Obtain troponin measurement immediately in patients with ECG changes or chest pain, as troponin elevation with appropriate clinical context is more diagnostic than isolated ECG changes 2, 3
• Perform continuous cardiac monitoring and serial ECGs to detect ST-segment elevation, new Q waves, or evolving ischemic changes 2, 4
• Obtain urgent echocardiography to assess ventricular function and detect mechanical complications such as ventricular septal defect or acute mitral regurgitation 2, 3, 4

Critical Decision Point: Distinguish MI Type

• Type 1 MI (acute plaque rupture with thrombotic occlusion) presents with ST-segment elevation, new Q waves, or regional wall motion abnormalities and requires consideration for emergency revascularization 2, 4
• Type 2 MI (supply-demand mismatch) is more common in the perioperative setting, caused by tachycardia, hypertension, hypotension, anemia, or hypoxemia—management focuses on correcting the underlying cause rather than invasive intervention 1, 2, 4

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Management of STEMI

Patients who develop STEMI after noncardiac surgery should be considered for guideline-directed medical therapy (GDMT), including consideration of invasive coronary angiography (ICA), balancing bleeding and thrombotic risks with the severity of the clinical presentation. 1

Immediate Medical Therapy

• Aspirin 162-325 mg should be administered immediately (loading dose) and continued indefinitely unless bleeding risk is prohibitive 1, 2, 3, 4
• Beta-blockers should be started immediately to reduce myocardial oxygen demand, targeting heart rate 60-70 bpm and systolic BP >100 mmHg 1, 2, 3, 4
• Intravenous anticoagulation with heparin should be initiated to prevent further thrombosis 2, 4
• ACE inhibitors are particularly beneficial in patients with low ejection fractions or anterior infarctions 1, 2, 3, 4
• High-intensity statin therapy should be initiated immediately 1

Revascularization Strategy for STEMI

• Emergency cardiac catheterization and PCI should be performed within 60 minutes from symptom onset if the patient can tolerate anticoagulation and antiplatelet therapy, particularly for hemodynamically unstable patients or those with large area of myocardium at risk 2, 4
• Weigh benefits of revascularization against bleeding risk from the surgical site—this decision must be individualized based on surgical bleeding risk, extent of myocardium at risk, and hemodynamic stability 2, 4
• Time to reperfusion is critical; any benefit requires angiography and revascularization within 12 hours of symptom onset 1, 2

Critical Contraindication

Fibrinolytic therapy is absolutely contraindicated in the perioperative period due to prohibitive bleeding risk at the surgical site. 1, 2, 4

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Management of NSTEMI

Patients with perioperative NSTEMI should receive GDMT as recommended for nonsurgical patients with spontaneous MI, with medical therapy including at least one antiplatelet (provided benefits outweigh bleeding risks), high-intensity statin, and in hemodynamically stable patients, beta-blockers, ACE inhibitors, and nitrates. 1

Medical Therapy for NSTEMI

• At least one antiplatelet agent (aspirin preferred) should be initiated, provided the benefits outweigh the bleeding risks 1
• High-intensity statin therapy should be started immediately 1
• Beta-blockers for symptomatic relief from angina and long-term cardiovascular risk reduction 1
• ACE inhibitors in patients whose hemodynamic status permits 1
• Nitrates may be considered for both symptomatic relief and risk reduction 1

Revascularization Strategy for NSTEMI

• Patients who develop NSTEMI after noncardiac surgery can be considered for ICA, balancing bleeding and thrombotic risks with the severity of clinical presentation 1
• Optimize medical therapy first, and reserve catheterization for patients with recurrent instability, ongoing ischemia, or heart failure 1, 5
• For hemodynamically stable patients, coronary angiography should be performed within 60 minutes from onset of recurrent discomfort 3

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Management of Myocardial Injury After Noncardiac Surgery (MINS)

Recognition and Cardiology Consultation

• Elevated postoperative troponin concentrations consistently identify surgical patients at increased risk for short- and long-term mortality 1
• Patients with MINS who receive cardiology consultation or transfer to a cardiology department have lower 30-day mortality—early referral for cardiology consultation is associated with significant reduction in early death 1
• Patients should be made aware of the MINS diagnosis during their surgical encounter 1

Medical Therapy for MINS

• Intensification of cardiovascular medical therapy (antiplatelets and statins) is associated with lower major adverse cardiovascular events at 1 year 1
• Among patients with perioperative MI, the use of aspirin and statins was associated with reduced 30-day mortality 1
• Postoperative statin use was associated with lower mortality at 1 year 1

Anticoagulation for MINS

• Dabigatran 110 mg twice daily initiated within 35 days of MINS significantly decreased the composite of major vascular events without increasing major bleeding in the MANAGE trial 1, 5
• Dabigatran was associated with excess minor and gastrointestinal bleeding 1
• Antiplatelet therapy at hospital discharge was associated with reduced risk of 1-year mortality in propensity-matched analysis 1

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Management of Mechanical Complications

Sudden hemodynamic deterioration with low cardiac output or pulmonary edema requires immediate consideration of mechanical defects (ventricular septal defect, acute mitral regurgitation, free wall rupture). 2, 3, 4

Diagnostic Approach

• New systolic murmur indicates possible ventricular septal rupture or acute mitral regurgitation 2, 4
• Perform urgent transesophageal echocardiography to establish precise diagnosis 2, 3

Surgical Intervention

• Emergency surgical repair (with or without CABG) is indicated for most mechanical complications including ventricular septal defect, mitral valve insufficiency, and free wall rupture 2, 4

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Pre-Discharge Requirements and Long-Term Management

Evaluation Before Discharge

• Left ventricular function should be evaluated with echocardiography before hospital discharge 1, 2, 3, 4
• Risk stratification with exercise testing or pharmacological stress testing should be performed after surgical recovery to assess risk of further cardiovascular events 1, 2, 3, 4

Standard Post-Infarction Medical Therapy

• Aspirin should be continued indefinitely 1, 2, 3, 4
• Beta-blockers for long-term cardiovascular risk reduction 1, 2, 3, 4
• ACE inhibitors, particularly for patients with low ejection fractions or anterior infarctions 1, 2, 3, 4
• High-intensity statin therapy should be prescribed 1, 2, 3, 4

Cardiovascular Risk Factor Modification

• Blood pressure control targeting <140/90 mmHg 3, 4
• LDL cholesterol <100 mg/dL 4
• Smoking cessation 1, 3, 4
• Management of diabetes and hyperlipidemia 1, 3

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Common Pitfalls and Caveats

• Do not routinely use fibrinolytic therapy in the perioperative period due to high bleeding risk at surgical sites—direct angioplasty is preferred if revascularization is needed 1, 2, 4
• Do not perform emergency revascularization routinely in postoperative patients when MI is not related to acute coronary occlusion—in cases of increased myocardial demand (postoperative tachycardia or hypertension), lowering heart rate or blood pressure is of greater benefit and carries less risk 1
• Recognize that most perioperative MI occurs in the postoperative period, not intraoperatively, and is often painless—serial cardiac enzymes and ECGs improve diagnostic yield 6

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Prognostic Context

• Perioperative MI carries extremely high mortality risk (40-70% for symptomatic MI) and substantially increases risk of future cardiac events dominated by cardiovascular death 1, 2, 4
• Patients presenting with perioperative MI have nearly one-third mortality or readmission rate at 30 days 1, 2