50 year old man has suffered a recurrent venous thrombosis, most likely from suboptimal prophylactic anticoagulation. The target INR for warfarin anticoagulation to prevent recurrent thromboembolism is 2.0-3.0. When a new thrombosis is diagnosed, therapeutic doses of heparin must be initiated. Simply increasing the warfarin dose to bring the INR into therapeutic range is inadequate, because warfarin is used for prophylaxis only, rather than for the treatment of acute thrombosis. For the same reason, switching to a different anticoagulant like dicumarol would be ineffective. After starting up heparin he should be restarted at a higher dose of warfarin.
of the inferior vena cava with a filter is primarily indicated only for patients in whom anticoagulation is contraindicated or in whom thrombosis has recurred despite adequate prophylactic anticoagulation. Neither of these considerations applies to this patient.
therapy is not necessary in most case of DVT of the leg. This mode of therapy can be considered in patients with extensive venous thrombosis, particularly involving extension into the inferior vena cava, in order to prevent long-term postphlebetic complications.
Of note, Low Molecular Weight Heparins (LMWH) will be of major therapoutic thrust soon. Recent studies have shown the LMWH to be of possible benefit in the treatment of D.V.T.'s (4,5,7,8 ) and in documented pulmonary embolism (6).
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