What is the recommended approach and management for radial Percutaneous Coronary Intervention (PCI) in patients with ST-Elevation Myocardial Infarction (STEMI)?

Radial PCI for STEMI: Recommended Approach

Radial artery access is the preferred approach for primary PCI in STEMI patients, as it significantly reduces mortality, major bleeding, and vascular complications compared to femoral access. 1

Primary Access Site Selection

The radial approach should be used as the default access site for all STEMI patients undergoing primary PCI when performed by operators experienced in this technique. 1

Evidence Supporting Radial Access

• Mortality benefit: Radial access reduces in-hospital mortality by approximately 45% (OR 0.55,95% CI 0.40-0.76) compared to femoral access in STEMI patients 2
• Bleeding reduction: Major bleeding occurs in only 1.4% with radial versus 2.9% with femoral approach (OR 0.51,95% CI 0.31-0.85) 2
• Access site complications: Vascular complications are reduced by 65% (2.1% vs 5.6%) with radial access 2
• Net clinical benefit: The composite of death, MI, stroke, and major bleeding/vascular complications is significantly lower with radial access (4.6% vs 11.0%) 3

Procedural Considerations

Timing and Transfer Protocols

• Direct catheterization laboratory transfer: STEMI patients should bypass the emergency department and proceed directly to the catheterization laboratory when radial PCI is planned 1
• Door-to-balloon time: While radial access may add approximately 1.5-4 minutes to procedure time 2, 4, this minimal delay does not negate the mortality and bleeding benefits 1
• Target time: Primary PCI should still be performed within 90 minutes of first medical contact regardless of access site 1

Operator Experience Requirements

Radial access should only be performed by operators experienced in both radial and femoral techniques to ensure optimal outcomes. 1, 3

• Studies demonstrating radial superiority were conducted in high-volume centers with operators proficient in both approaches 2, 3
• Crossover rates from radial to femoral should be <5% in experienced hands (reported as 3.7% in trials) 3
• Independent operators show greater benefit from radial access compared to trainees 5

Antiplatelet and Anticoagulation Strategy

Pre-PCI Medications

• Aspirin: 162-325 mg orally or IV before PCI 1
• P2Y12 inhibitor loading: Administer as early as possible or at time of PCI 1
  • Prasugrel 60 mg (avoid if prior stroke/TIA) 1
  • Ticagrelor 180 mg 1
  • Clopidogrel 600 mg (only if prasugrel/ticagrelor unavailable or contraindicated) 1

Anticoagulation Options

For radial PCI in STEMI, the following anticoagulation regimens are recommended: 1

• Unfractionated heparin (UFH): Weight-adjusted IV bolus (70-100 U/kg, or 50-60 U/kg if GP IIb/IIIa inhibitor used) with additional boluses to maintain therapeutic ACT 1
• Bivalirudin: 0.75 mg/kg bolus followed by 1.75 mg/kg/h infusion (with or without prior UFH treatment) 1
• Enoxaparin: If already administered, can be continued during PCI 1
• Fondaparinux: NOT recommended for primary PCI 1

GP IIb/IIIa Inhibitors

• Reasonable to administer at time of primary PCI in selected patients receiving UFH 1
• Options include abciximab, high-bolus-dose tirofiban, or double-bolus eptifibatide 1
• Intracoronary abciximab may be considered 1

Stent Selection

Both bare-metal stents (BMS) and drug-eluting stents (DES) are appropriate for primary PCI in STEMI. 1

Stent Choice Algorithm

• DES preferred for most patients to reduce target vessel revascularization 1
• BMS should be used in patients with: 1
  • High bleeding risk
  • Inability to comply with 12 months of dual antiplatelet therapy
  • Anticipated invasive or surgical procedures within the next year
  • Inability to afford prolonged DAPT

Post-PCI Management

Dual Antiplatelet Therapy Duration

Continue DAPT (aspirin plus P2Y12 inhibitor) for 12 months after primary PCI unless contraindicated due to excessive bleeding risk. 1

• Aspirin: 75-100 mg daily indefinitely 1
• P2Y12 inhibitor: Continue for 12 months (ticagrelor or prasugrel preferred over clopidogrel) 1
• Proton pump inhibitor: Add for patients at high risk of GI bleeding 1

Additional Therapies

• Beta-blockers: Initiate within 24 hours in patients with heart failure or LVEF <40% unless contraindicated 1
• ACE inhibitors: Start within 24 hours in all anterior STEMI patients 6
• High-intensity statin: Initiate as early as possible 6

Special Populations and Situations

Cardiogenic Shock

Primary PCI via radial access should still be performed in patients with cardiogenic shock, as the mortality benefit is maintained. 1

• Radial access does not compromise procedural success in shock patients 2
• The bleeding reduction benefit is particularly important in hemodynamically unstable patients 1

Late Presentation (12-24 hours)

Primary PCI is reasonable via radial access if clinical or ECG evidence of ongoing ischemia exists between 12-24 hours after symptom onset. 1

When Radial Access Fails

• Crossover to femoral: Should occur promptly if radial access unsuccessful after reasonable attempts 3
• Acceptable crossover rate is <5% in experienced centers 3
• Do not persist with radial attempts if causing significant delay to reperfusion 1

Common Pitfalls to Avoid

• Inexperienced operators: Do not attempt radial access without adequate training and experience in both radial and femoral techniques 1, 3
• Excessive procedure time: If radial access is taking significantly longer, convert to femoral to avoid delays in reperfusion 4
• Inadequate anticoagulation: Ensure therapeutic ACT levels are maintained throughout the procedure 1
• Premature DAPT discontinuation: This increases stent thrombosis risk, particularly with DES 1
• Using prasugrel in stroke patients: Absolute contraindication due to increased bleeding risk 1