Indications for reperfusion therapy for STEMI

Reperfusion therapy aims to reopen the occluded artery and re-establish blood flow as soon as possible. Reperfusion can be achieved with mechanical therapy (percutaneous coronary intervention) or drug therapy (thrombolytic therapy)—see Choice of reperfusion therapy for STEMI.

For a patient with significant ST elevation or left bundle branch block (that is presumed to be new), use reperfusion therapy if symptoms consistent with myocardial infarction (eg chest pain, chest discomfort or pressure, shortness of breath, pulmonary oedema, sweating, dizziness, light-headedness) started within the 12 hours preceding presentation.

For patients presenting more than 12 hours after the onset of symptoms, myocardial infarction may already be complete, but reperfusion therapy may be considered if there are signs of:

• ongoing ischaemia (eg persistent pain and dynamic electrocardiogram [ECG] changes)
• viable myocardium (preservation of R waves in infarct-related ECG leads)
• major complications (eg cardiogenic shock, heart failure, malignant arrhythmias).

Advanced age, frailty and comorbidities influence a patient’s overall survival, and should be considered when deciding to intervene with reperfusion therapy.