What is the recommended timing for Percutaneous Coronary Intervention (PCI) in a patient presenting with ST-Elevation Myocardial Infarction (STEMI)?

Timing for PCI in STEMI

Primary PCI should be performed within 90 minutes of first medical contact for patients presenting to a PCI-capable hospital, and within 120 minutes for patients requiring transfer from a non-PCI-capable facility. 1

Time Goals Based on Presentation Location

Direct Presentation to PCI-Capable Hospital

• The target is ≤90 minutes from first medical contact to balloon inflation for patients presenting directly to a facility with PCI capability 1
• For patients presenting within 120 minutes of symptom onset or arriving directly at a PCI-capable hospital, the European Society of Cardiology recommends an even more aggressive goal of ≤60 minutes 1
• The catheterization laboratory must be available 24 hours a day, 7 days a week, and be able to start primary PCI within 60 minutes from the initial call 1

Transfer from Non-PCI-Capable Hospital

• The system goal extends to ≤120 minutes from first medical contact to balloon inflation when patients require interhospital transfer 1
• The door-in-door-out (DIDO) time at the referring hospital should be ≤30 minutes to facilitate achieving the overall 120-minute goal 1
• Patients should bypass the emergency department at the receiving PCI center and transfer directly to the catheterization laboratory 1

Time-Based Treatment Algorithm

Symptom Duration <3 Hours

• Primary PCI is generally preferred if the expected door-to-balloon time minus the expected door-to-needle time is ≤1 hour 1, 2
• If this time differential is >1 hour, fibrinolytic therapy is generally preferred 1, 2

Symptom Duration >3 Hours but <12 Hours

• Primary PCI is generally preferred regardless of the time differential, with the goal of achieving balloon inflation within 90 minutes of first medical contact 1, 2
• This recommendation reflects the superior efficacy of mechanical reperfusion over fibrinolysis when adequate time has elapsed since symptom onset 1

Symptom Duration 12-24 Hours

• Primary PCI is reasonable (Class IIa recommendation) if there is clinical and/or electrocardiographic evidence of ongoing ischemia 1
• For asymptomatic higher-risk patients presenting 12-24 hours after symptom onset, primary PCI might be considered (Class IIb recommendation) 1

Special Clinical Scenarios

Cardiogenic Shock or Severe Heart Failure

• Primary PCI should be performed as soon as possible, irrespective of time delay from symptom onset 1
• For patients <75 years developing cardiogenic shock within 36 hours of MI, revascularization should occur within 18 hours of shock onset 1, 2
• The medical contact-to-balloon time should be as short as possible, ideally within 90 minutes, for patients with severe heart failure (Killip class 3) presenting within 12 hours 1, 2

Contraindications to Fibrinolysis

• Primary PCI should be performed as soon as possible in patients with contraindications to fibrinolytic therapy who have ischemic symptoms for less than 12 hours 1

Failed Fibrinolysis

• Immediate rescue PCI is reasonable (Class IIa recommendation) for patients with evidence of failed fibrinolysis or infarct artery reocclusion 1
• The European guidelines recommend rescue PCI within 45-60 minutes after starting fibrinolytic administration if thrombolysis has failed 1

Successful Fibrinolysis

• Coronary angiography 3-24 hours after fibrinolytic therapy is reasonable (Class IIa recommendation) for hemodynamically stable patients with evidence of successful fibrinolysis 1
• This early invasive strategy after successful fibrinolysis reduces reinfarction and recurrent ischemic events 1

Critical Implementation Factors

Facility and Operator Requirements

• Primary PCI should be performed by operators who perform >75 PCI procedures per year, ideally ≥11 primary PCIs annually for STEMI 1, 2
• The facility should perform >200 PCI procedures per year, of which ≥36 are primary PCI for STEMI, and must have cardiac surgery capability 1, 2
• Hospitals unable to consistently meet the 90-minute (or 120-minute for transfers) time goals should use fibrinolytic therapy as their primary reperfusion strategy 2

Pre-Hospital System Optimization

• First medical contact to first ECG should be ≤10 minutes 1
• Ambulance teams must be trained and equipped to identify STEMI with 12-lead ECG and telemetry as necessary 1
• Pre-hospital diagnosis with field triage directly to catheterization laboratories (bypassing emergency departments) significantly improves door-to-balloon times 3, 4

Common Pitfalls to Avoid

Emergency Department Delays

• Patients who transit through the emergency department rather than going directly to the catheterization laboratory have significantly longer first medical contact to balloon times, even when they live closer to the PCI center 4
• Direct transfer to the catheterization laboratory is strongly recommended to avoid this delay 1, 4

Late Presentation (>24 Hours)

• PCI of a totally occluded infarct artery >24 hours after STEMI should not be performed in asymptomatic, hemodynamically stable patients with 1- or 2-vessel disease who lack evidence of severe ischemia (Class III: No Benefit) 1
• However, PCI of a hemodynamically significant stenosis in a patent infarct artery >24 hours after STEMI may be considered as part of an invasive strategy (Class IIb) 1

Multivessel Disease

• PCI should not be performed in a noninfarct artery at the time of primary PCI in patients without hemodynamic compromise (Class III: Harm) 1
• Delayed PCI of noninfarct arteries can be performed later if clinically indicated 1