Heparin, consider Warfarin

In present times, because of early mobilization and shorter stays in hospital, venous thrombosis in the legs and resulting pulmonary embolism has declined to a large degree. In persons with acute myocardial infarction, prophylactic low-dose heparin has reduced the incidence of venous thrombosis in the legs. It is considered as a reasonable alternative to warfarin in selected patients. Preventive anlicoagulalion may be indicated in some cases to prevent strokes due to left ventricular mitral thrombi embolizing in tire brain. 

Caution should be used when considering neuraxial techniques in patients who have recently discontinued warfarin therapy, and prothrombin time (PT/INR) should be assessed prior to needle placement. Therapy should be withheld 4-5 days prior to the operation. It is important to note that concomitant use of other medications that affect the clotting mechanism, such as aspirin or heparin, may interact synergistically with warfarin without any demonstrated prolongation of the PT/INR. Other medications that may potentiate... 

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