Management of Oral Anticoagulant Treatment in Patients with Venous Thromboembolism

ABSTRACT

Oral anticoagulants (OAs) are the drugs of choice for the prevention of recurrence and death in patients with venous thromboembolism (VTE). Oral anticoagulant treatment (OAT) aims to retard blood coagulation to obtain maximum protection against thromboembolic events with the lowest risk of bleeding. The intensity of OAT is ascertained by measuring the prothrombin time (PT), which is expressed as the international normalized ratio (INR). The efficacy and safety of these drugs depends on the ability to maintain the level of anticoagulation as close as possible to the therapeutic target (INR = 2.5) or inside the therapeutic range (INR = 2.0 to 3.0). Given that dosage of oral anticoagulants varies from patient to patient and within the single patient, clinical and laboratory (biological effect of the drug) check-ups must be performed periodically. The management of patients with VTE, as well as that of other patients receiving OAT, includes medical controls and expertise that are better available in specialized centers (anticoagulation clinics).

KEYWORDS

Venous thromboembolism - oral anticoagulants - warfarin - management - laboratory control

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