To the Editor: In the Pulmonary Embolism Thrombolysis (PEITHO) study (April 10 issue),1 a bolus of unfractionated heparin was withheld from 303 patients because they had just received subcutaneous low-molecular-weight heparin or fondaparinux. Low-molecular-weight heparin in particular has a slow onset of action, taking 4 to 6 hours to reach full effect.2 This delay in the effect of treatment ma...

BACKGROUND Despite its limitations, unfractionated heparin has been the standard anticoagulant used during percutaneous coronary intervention (PCI). Several small studies have suggested that intravenous enoxaparin may be a safe and effective alternative. Our primary aim was to assess the safety of enoxaparin as compared with that of unfractionated heparin in elective PCI. METHODS In this pros...

Introduction: We report a patient with history of red meat allergy, or alpha-gal syndrome, who had an urticarial rash after exposure to unfractionated heparin at dose typically used for prophylaxis deep venous thrombosis. Although anaphylactic reactions have been reported systemic intravenous heparin, we believe this case is the first immunoglobulin E–mediated reaction subcutaneous prophylactic...

BACKGROUND Unfractionated heparin has been used extensively for the treatment of unstable angina/non-Q wave myocardial infarction but it has several disadvantages. Low-molecular weight heparins are now recommended although they are 3-5 times costlier than unfractionated heparin since they are convinient to administer and do not require activated thromboplastin time monitoring. Whereas enoxapari...

Unfractionated heparin and low molecular weight heparin are the most commonly used antithrombotic and thromboprophylactic agents in hospital practice. Extended out-of-hospital treatment is inconvenient in that these agents must be administered parenterally. Current research is directed at development of a safe and effective oral antithrombotic agent as an alternative for the effective, yet diff...

The adhesion of sickle erythrocytes to vascular endothelium is important to the generation of vascular occlusion. Interactions between sickle cells and the endothelium use several cell adhesion molecules. We have reported that sickle cell adhesion to endothelial cells under static conditions involves P-selectin. Others have shown that sickle cell adhesion is decreased by unfractionated heparin,...

i t n ercutaneous coronary intervention (PCI) is frequently erformed in patients who received fibrinolytic therapy for cute myocardial infarction (MI). Currently, unfractionated eparin is the most commonly used antithrombin therapy in his situation. However, unfractionated heparin has certain imitations. It has a narrow therapeutic range, monitoring of he activated clotting time is required, an...

BACKGROUND The standard initial treatment of hemodynamically stable patients with pulmonary embolism is intravenous unfractionated heparin, requiring laboratory monitoring and hospitalization. METHODS We conducted a randomized, open-label trial involving 2213 patients with acute symptomatic pulmonary embolism to compare the efficacy and safety of the synthetic antithrombotic agent fondaparinu...

BACKGROUND AND PURPOSE There is no consensus whether to use unfractionated heparin or low-molecular weight heparin for the treatment of cerebral venous thrombosis. We examined the effect on clinical outcome of each type of heparin. METHODS A nonrandomized comparison of a prospective cohort study (the International Study on Cerebral Vein and Dural Sinus Thrombosis) of 624 patients with cerebra...