A 68-year old woman comes to the physician for routine follow-up for a cardiac arrhythmia. She takes metoprolol and feels well. She has no other medical problems. ECG tracing is shown. The patient is started on anticoagulation. One week later, the international normalized ratio is 2.5 (normal is <1.1) and the partial thromboplastin time is 39 sec. Which of the following is the mechanism of action of the anticoagulant this patient was most likely given? • A. Activation of antithrombin IH • B. Enzymatic conversion of plasminogen to plasmin OC. Inhibition of carboxylation of specific clotting factors • D. Inhibition of glycosylation of specific clotting factors • E. Inhibition of platelet activation by receptor binding © F. Inhibition of the adenosine diphosphate pathway
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The most commonly used oral anticoagulant that elevates INR is warfarin. The mechanism of action of warfarin is the inhibition of the carboxylation of specific clotting factors (Factors II, VII, IX, and X, and proteins C and S). Show more…
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