What are the American Heart Association (AHA) guidelines for primary percutaneous coronary intervention (PCI)?

AHA Guidelines for Primary Percutaneous Coronary Intervention (PCI)

Primary PCI should be performed in patients with STEMI within 12 hours of symptom onset, with a goal door-to-balloon time of 90 minutes for PCI-capable hospitals and 120 minutes for patients requiring transfer from non-PCI capable facilities. 1

Primary PCI Indications (Class I Recommendations)

Primary PCI is strongly recommended in the following scenarios:

• STEMI symptoms within 12 hours of onset (Level of Evidence: A) 1
• Severe heart failure or cardiogenic shock, regardless of time delay from MI onset (Level of Evidence: B) 1
• Contraindications to fibrinolytic therapy with ischemic symptoms <12 hours (Level of Evidence: B) 1
• PCI-capable hospital: door-to-balloon time goal within 90 minutes of first medical contact (Level of Evidence: B) 1
• Non-PCI capable hospital: door-to-balloon time goal within 120 minutes of first medical contact (Level of Evidence: B) 1

Reasonable Primary PCI Indications (Class IIa Recommendations)

PCI is reasonable in these situations:

• Clinical/electrocardiographic evidence of ongoing ischemia between 12-24 hours after symptom onset (Level of Evidence: B) 1
• Patients ≥75 years with ST elevation or LBBB who develop shock within 36 hours of MI and can receive revascularization within 18 hours of shock (Level of Evidence: B) 1
• Failed fibrinolysis with moderate to large area of myocardium at risk (Level of Evidence: B) 1
• Successful fibrinolysis: coronary angiography 3-24 hours after fibrinolytic therapy in hemodynamically stable patients (Level of Evidence: A) 1

Potential Primary PCI Indications (Class IIb Recommendations)

PCI might be considered in:

• Asymptomatic higher-risk patients presenting between 12-24 hours after symptom onset (Level of Evidence: C) 1
• Stable patients who did not undergo cardiac catheterization within 24 hours of STEMI onset (pre-discharge angiography) (Level of Evidence: C) 1

Contraindications to Primary PCI (Class III Recommendations)

PCI should NOT be performed in:

• Non-infarct artery during primary PCI in patients without hemodynamic compromise (Level of Evidence: B) 1
• Asymptomatic patients >12 hours after STEMI onset who are hemodynamically and electrically stable (Level of Evidence: C) 1
• Patients where risks of revascularization likely outweigh benefits (Level of Evidence: C) 1
• Patients who decline invasive care (Level of Evidence: C) 1

Operator and Institutional Requirements

For optimal outcomes, primary PCI should be performed by:

• Experienced operators performing >75 PCI procedures/year (ideally at least 11 PCIs for STEMI/year) 1
• Centers performing >200 PCI procedures/year (at least 36 primary PCIs for STEMI) with cardiac surgery capability 1

Timing Considerations and Systems of Care

• The mortality benefit of primary PCI over fibrinolysis diminishes with increasing time delays 2
• Pre-hospital ECG interpretation and direct transport to PCI centers significantly reduces door-to-balloon times 3
• Integrated regional STEMI networks improve timely access to primary PCI 3, 4

Adjunctive Pharmacotherapy

• Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is essential 5
• Preferred P2Y12 inhibitors include ticagrelor or prasugrel, with clopidogrel as an alternative 5
• Anticoagulation options include unfractionated heparin, bivalirudin, or enoxaparin 5, 4

Special Considerations

• For cardiogenic shock: Primary PCI should be performed regardless of time delay from MI onset 1
• For elderly patients (≥75 years): Consider primary PCI for those with good functional status who are suitable for revascularization 1
• For fibrinolytic-ineligible patients: Primary PCI is recommended within 12 hours of symptom onset 1

Common Pitfalls to Avoid

• Delaying primary PCI beyond recommended timeframes
• Performing PCI on non-infarct arteries during primary PCI in hemodynamically stable patients
• Neglecting to establish systems for rapid transfer from non-PCI capable hospitals
• Underutilizing pre-hospital ECG and direct transport protocols
• Failing to consider reperfusion injury as a complication of primary PCI 6

Primary PCI remains the preferred reperfusion strategy for STEMI when performed in a timely manner by experienced operators at high-volume centers. Time to reperfusion is critical, and healthcare systems should be organized to minimize delays in delivering this life-saving therapy.