Related Experiment Videos
New heparin dosing recommendations for patients with acute coronary syndromes
V Menon1, S D Berkowitz, E M Antman
1Division of Cardiology, St. Luke's-Roosevelt Hospital Center, Columbia University, New York, NY 10025, USA. Vmenon@slrhc.org
Insights
Unfractionated heparin remains crucial for acute coronary syndromes. New guidelines detail dosing for myocardial infarction and unstable angina, aiming for specific activated partial thromboplastin time levels to optimize treatment and minimize bleeding risks.
Area of Science:
- Cardiology
- Pharmacology
- Thrombosis Management
Background:
- Unfractionated heparin is a cornerstone in treating acute coronary syndromes despite advances in other therapies.
- Current American College of Cardiology/American Heart Association guidelines provide updated recommendations for heparin dosing.
Purpose of the Study:
- To review and explain the rationale behind new unfractionated heparin dosing regimens for acute coronary syndromes.
- To discuss the bleeding risks associated with heparin, particularly in combination with other antithrombotic agents.
- To explore the correlation between activated partial thromboplastin time and cardiac events.
Main Methods:
- Review of current American College of Cardiology/American Heart Association guidelines on heparin dosing.
- Analysis of recommended initial bolus and infusion rates for ST-elevation myocardial infarction, non-ST elevation myocardial infarction, and unstable angina.
- Examination of the target activated partial thromboplastin time range (50-70 seconds).
Main Results:
- Specific dosing regimens are recommended: 60 U/kg bolus (max 4000 U) followed by 12 U/kg/h infusion (max 1000 U/h) with alteplase for ST-elevation myocardial infarction.
- For non-ST elevation myocardial infarction and unstable angina, 60-70 U/kg bolus (max 5000 U) followed by 12-15 U/kg/h infusion is advised.
- The goal is to maintain activated partial thromboplastin time between 50 and 70 seconds.
Conclusions:
- Updated heparin dosing strategies aim to optimize efficacy in acute coronary syndromes.
- Understanding and managing bleeding risks, especially with concurrent therapies, is critical.
- Monitoring activated partial thromboplastin time is essential for effective heparin therapy and patient outcomes.
Abstract:
Despite major innovations in antithrombotic and antiplatelet therapy, unfractionated intravenous heparin is widely used to treat acute coronary syndromes. Recommendations for unfractionated heparin dosing in acute myocardial infarction and unstable angina have been issued in two recent American College of Cardiology/American Heart Association guidelines. An initial heparin bolus of 60 U/kg (maximum, 4000 U) followed by a 12-U/kg/h infusion (maximum 1000 U/h) is recommended with alteplase for ST-elevation myocardial infarction. When intravenous heparin is administered for myocardial infarction with non-ST elevation and unstable angina, an initial bolus of 60 to 70 U/kg (maximum, 5000 U) followed by a 12- to 15-U/kg/h infusion is recommended. The goal is to achieve an activated partial thromboplastin time of 50 to 70 seconds. Here, we review these new dosing regimens and explain the rationale for their use. We also review the risk of bleeding with heparin, especially when administered concurrently with aspirin, thrombolytic agents, and glycoprotein IIb/IIIa antagonists, and the relationship between activated partial thromboplastin time and cardiac events.