Deep Venous Thrombosis in a Patient with a Complex Medication Regimen


Venous thromboembolism (VTE) includes both deep vein thrombosis (DVT) and pulmonary embolism (PE). In the United States, up to 1 million individuals are affected annually by either DVT or PE, and each year between 100,000 and 296,000 VTE-related deaths occur in the US, and approximately 370,000 occur in Europe.1 As a result, VTE places a considerable economic and clinical morbidity and mortality burden on the health care system.

When approaching VTE, it is important to first identify whether the VTE is a provoked versus an unprovoked or idiopathic VTE. A provoked VTE is one that occurs secondary to a provocative factor, such as surgery or trauma, whereas an unprovoked VTE is characterized by failure to establish an identifiable provocative factor at diagnosis.2 Unprovoked VTEs frequently lead to investigations of thrombophilias or "hypercoagulable states" to help understand why the patient developed a VTE. According to the most recent American College of Chest Physicians (CHEST) evidence-based clinical practice guidelines, provoked VTE should be treated for three months, and unprovoked VTE requires indefinite treatment as long as the benefit of anticoagulation outweighs the risk of bleeding.

Case Presentation

A 47-year-old male with a history of depression, hypertension, and human immunodeficiency virus sustains a left ankle fracture after a skiing injury. A cast worn for four weeks was transitioned to a splint last week. The patient presents to your office with cramping pain in the left calf and swelling for the past day and a half. His medications include citalopram, amlodipine, combination emtricitabine, tenofovir, and efavirenz, and a multivitamin. The patient states his schedule has limited flexibility for frequent blood checks and inquires if he can take one of the "new pills" for treatment. Recent bloodwork taken about two weeks ago demonstrates a creatinine clearance of 140 mL/min, white blood cell count of 7.2 thou/uL, hemoglobin 14.3 g/dL, platelet count 200 thou/uL and liver function panel is within normal limits.

An ultrasound of the lower extremities is obtained to assess for DVT. The images are shown below.

Figure 1

Figure 1
In Figure 1, the ultrasound demonstrates an acute left popliteal vein DVT, hallmarked by dilation and non-compressibility (arrow) of the left popliteal vein (arrow).

Figure 2

Figure 2
Figure 2 shows a longitudinal view of the popliteal vein demonstrating no flow in the vein by color Doppler.

Which of the following describes is the best course of action for this patient?

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