- Question
- To determine whether three fibrinolytic agents (streptokinase, tPA and anistreplase) differ in mortality in suspected acute myocardial infarction, and whether adding subcutaneous heparin to aspirin improves survival.
- Design
- Randomised factorial trial of 41299 patients in 914 hospitals; patients were enrolled up to 24 hours (median 4 hours) after symptom onset.
- Population
- Patients with suspected acute myocardial infarction presenting within 24 hours of onset. A pre-specified subset comprised those presenting within 6 hours with ST elevation on the electrocardiogram.
- Intervention
- Randomisation to streptokinase (1.5 MU over about 1 hour), tPA (duteplase, 0.60 MU/kg over about 4 hours) or anistreplase (30 U over about 3 minutes). All received aspirin (162 mg/day) and half also received subcutaneous calcium heparin (12500 IU twice daily for 7 days or until discharge).
- Control
- For the heparin comparison: aspirin alone. For the fibrinolytics, each agent was compared with the others, with streptokinase as the reference in the reported data.
- Primary outcome
- 35-day mortality.
- Results
- Aspirin plus heparin vs aspirin alone: 35-day mortality of 10.3% vs 10.6%, not significantly different. Streptokinase vs anistreplase: 35-day mortality of 10.6% vs 10.5%, not significantly different, nor in the early-presenting ST-elevation subset (10.0% vs 9.9%).
- Safety
- Heparin was associated with more major non-cerebral bleeds (1.0% vs 0.8%) and more cerebral haemorrhage (0.56% vs 0.40%). Anistreplase caused more cerebral haemorrhage than streptokinase (0.55% vs 0.24%) and more persistent allergic reactions.
- Conclusion
- There were no short-term mortality differences among the compared fibrinolytics and no significant benefit from adding subcutaneous heparin to aspirin, at the cost of more bleeding.
- Why it matters
- It showed that the choice among these fibrinolytic agents did not change short-term survival and that routine subcutaneous heparin on top of aspirin offered limited benefit relative to its bleeding risk.
Card generated automatically with AI from the abstract of the original publication and the trial registry; every figure was checked against those sources. It may contain errors: verify the data at the source before using it for clinical decisions.
Generated on October 10, 2026