SELECTION CRITERIA

Acute chest discomfort characteristic of myocardial infarction
ECG criteria for ST-elevation MI (a, b, or c):

ST elevation 0.1 mV (1 mm) in at least 2 leads of either:


Inferior group: II, III, aVF
Lateral group: I, aVL, V₅, V₆


ST elevation 0.2 mV (1 mm) in at least 2 contiguous anterior leads (V₁-V₄)
New LBBB

Primary PCI not available, or delay to PCI from first medical contact would be >120 min.

ST elevation 0.1 mV (1 mm) in at least 2 leads of either:


Inferior group: II, III, aVF
Lateral group: I, aVL, V₅, V₆


ST elevation 0.2 mV (1 mm) in at least 2 contiguous anterior leads (V₁-V₄)
New LBBB

Inferior group: II, III, aVF
Lateral group: I, aVL, V₅, V₆

ASSESS FOR CONTRAINDICATIONS

Prior intracranial bleeding
Intracranial malignancy or vascular malformation
Ischemic stroke or head trauma in previous 3 months
Aortic dissection
Active bleeding (with exception of menses)
Internal bleeding in previous 4 weeks
Severe hypertension (systolic >180 or diastolic >110)
Prolonged (>10 min) CPR chest compressions
INR 2.0 on warfarin, or known bleeding diathesis
Pregnancy

FIBRINOLYTIC DRUG : INTRAVENOUS DOSAGE
Streptokinase : 1.5 million U over 60 min
Alteplase : 15-mg bolus, then 0.75 mg/kg (up to 50 mg) over 30 min, then 0.5 mg/kg (up to 35 mg) over 60 min
Reteplase : 10 U over 2 min; repeat same dose 30 min later
Tenecteplase : Single bolus of 0.53 mg/kg over 10 s

Also administer IV heparin 60-U/kg bolus (maximum 4000 U) followed by 12 (U/kg)/h (maximum 1000 U/h), then adjusted to maintain aPTT at 1.5-2 control (~50-70 s) for 48 h (evidence for heparin benefit with streptokinase is weak)

SUBSEQUENT CORONARY ANGIOGRAPHY RESERVED FOR

Failure of reperfusion (persistent chest pain or ST elevation after 90 min)
Spontaneous recurrent ischemia during hospitalization
High risk features: e.g., extensive ST elevation, heart failure, hypotension

End