A. Fibrinolytic therapy has its greatest efficacy within 3 hours of symptom onset
B. Fibrinolytic therapy should not be used to treat STEMI if symptom onset was greater than 12 hours
C. Simultaneous anticoagulation therapy during fibrinolytic therapy is optional
D. Fibrinolytic therapy is indicated for high risk non-ST elevation myocardial infarction patients at facilities not capable of percutaneous coronary intervention
Fibrinolytic therapy must be instituted within 24 hours of symptom onset. After this time frame, fibrinolytic therapy is contraindicated and likely will not be effective since intracoronary thrombus will be older and more organized. Fresh thrombus breaks down the best with fibrinolytic therapy. Note that fibrinolytic therapy is always given simultaneously with anticoagulation using unfractionated heparin or low molecular weight heparin. Fibrinolytic therapy is not indicated for non-ST segment elevation myocardial infarction in any situation.