Related Experiment Videos
Antithrombotic therapy in acute coronary syndromes: key notes from ESSENCE and TIMI 11B
1Department of Medical and Radiological Sciences, Cardiology, The Royal Infirmary, Edinburgh, Scotland, UK.
Insights
Enoxaparin, a low-molecular-weight heparin, significantly reduces ischemic events in acute coronary syndromes compared to unfractionated heparin. This finding offers improved treatment options for patients unresponsive to current therapies.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Platelet activation and thrombus formation are central to acute coronary syndromes (ACS).
- Current ACS management relies on antithrombotic and antiplatelet therapies, including heparin and aspirin.
- These standard treatments are ineffective for a substantial number of patients.
Purpose of the Study:
- To evaluate the efficacy of low-molecular-weight heparin (LMWH) enoxaparin in managing ACS.
- To compare enoxaparin's effectiveness against unfractionated heparin in reducing ischemic events.
Main Methods:
- Analysis of two large clinical studies: ESSENCE and TIMI 11B.
- Comparison of enoxaparin treatment versus unfractionated heparin in ACS patients.
- Meta-analysis of pooled data from ESSENCE and TIMI 11B studies.
Main Results:
- Enoxaparin significantly reduced the risk of death, myocardial infarction, or recurrent angina by 20% at 14 days in the ESSENCE study.
- Enoxaparin demonstrated a significant reduction in death, myocardial infarction, or urgent revascularization within 48 hours, with sustained benefits in TIMI 11B.
- A meta-analysis confirmed a consistent 20% lower risk of death or myocardial infarction with enoxaparin compared to unfractionated heparin.
Conclusions:
- Enoxaparin offers a significant therapeutic advantage over unfractionated heparin for patients with acute coronary syndromes.
- The consistent superiority of enoxaparin suggests its potential as a preferred antithrombotic agent in ACS.
- Pharmacologic heterogeneity among LMWHs may explain variable results with agents other than enoxaparin.
Abstract:
Platelet activation and thrombus formation are key events in the pathogenesis of acute coronary syndromes (unstable angina and non-Q-wave myocardial infarction). Therefore, current management of these conditions consists of antithrombotic and antiplatelet therapy, principally heparin and oral aspirin. However, such treatment is unsuccessful in a significant proportion of patients. Two recent large studies with the low-molecular-weight heparin (LMWH) enoxaparin have shown that this agent significantly reduces the risk of major ischemic events compared with unfractionated heparin. In the Efficacy and Safety of Subcutaneous Enoxaparin in Non-Q-Wave Coronary Events (ESSENCE) study, treatment with enoxaparin for 2 to 8 days reduced the risk of death, myocardial infarction, or recurrent angina by 20% at 14 days compared with treatment with unfractionated heparin. In the Thrombolysis in Myocardial Infarction (TIMI) 11B study, enoxaparin was associated with a significant reduction in the risk of death, myocardial infarction, or urgent revascularization compared with unfractionated heparin, which became apparent within 48 hours; this benefit was maintained during outpatient treatment for 5 weeks. A meta-analysis of these two studies showed that the risk of death or myocardial infarction was consistently approximately 20% lower in enoxaparin-treated patients than in heparin-treated patients. In contrast, studies with other LMWHs have not shown consistent superiority over unfractionated heparin. This may reflect the pharmacologic heterogeneity of LMWH and/or differences in trial design.