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Platelet-based Detection of Nitric Oxide in Blood by Measuring VASP Phosphorylation
Published on: January 7, 2019
Does nitroglycerin induce heparin resistance?
N E Lepor1, D K Amin, L Berberian
1Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048.
Clinical Cardiology
|August 1, 1989
Summary
Intravenous nitroglycerin does not cause heparin resistance. Studies showed no significant changes in activated partial thromboplastin time in vitro or in patients receiving nitroglycerin during heparin therapy.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Heparin is a critical anticoagulant in cardiovascular procedures.
- Nitroglycerin is frequently used in patients undergoing percutaneous coronary interventions.
Purpose of the Study:
- To investigate whether intravenous nitroglycerin induces heparin resistance.
- To assess the impact of nitroglycerin on anticoagulation efficacy.
Main Methods:
- In vitro assays using activated partial thromboplastin time (aPTT) and thrombin time (TT).
- Prospective study of 10 patients undergoing coronary angioplasty, measuring aPTT before, during, and after nitroglycerin infusion while on continuous heparin.
- Standard heparin dosing was maintained throughout the patient study.
Main Results:
- Nitroglycerin did not alter aPTT or TT in vitro at concentrations up to 250 micrograms/ml.
- The maximum reduction in aPTT in vitro was 7%.
- In patients, aPTT values remained statistically similar (p=0.61) when on heparin alone, with nitroglycerin, and after nitroglycerin cessation.
Conclusions:
- Intravenous nitroglycerin does not induce heparin resistance.
- Short-term administration of nitroglycerin does not interfere with heparin's anticoagulant effect in patients undergoing coronary angioplasty.
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