Question

A 60-year-old patient experienced a sudden onset of chest pain and shortness of breath and was subsequently diagnosed with a pulmonary embolism in the emergency department. The patient has been started on an intravenous heparin infusion. How does this drug achieve therapeutic effect?

a) By inhibiting platelet aggregation on vessel walls and promoting fibrinolysis
b) By promoting the rapid excretion of vitamin K by the gastrointestinal mucosa
C) By inhibiting the action of vitamin K at its sites of action
D) By inactivating clotting factors and thus stopping the coagulation cascade

Answer 1

The answer is letter D.

Step-by-step explanation:

By inactivating clotting factors and thus stopping the coagulation cascade.

Heparin, alomg with antithrombin, rapidly promotes the incativation of factor X, which, in turn, prevents the conversion of prothrombin to thrombin. Heparin does not achieve its therapeutic effect through the excretion or inhibition of vitamin K or by inhibiting platelet aggregation.