Deep venous thrombosis (DVT) is often associated with intrinsic coagulopathy, impaired fibrinolysis, recent surgery, trauma, immobilization, increased estrogen (pregnancy, oral contraceptives) with smoking, malignancy, prior DVT, inflammatory disease processes, or coronary artery disease. Intravenous catheters are also a major cause of DVT, particularly in the upper extremity. Unilateral swelling and tenderness, classically in the calf and thigh, are characteristic. Doppler ultrasonography is the screening test of choice in most institutions. In selected low-risk patients, a quantitative D-dimer study may be used to rule out DVT. Cellulitis, lymphedema, heart failure, compartment syndrome, myositis, arthritis, and superficial phlebitis should also be considered.
Management and Disposition
Classic treatment is heparin anticoagulation and admission for warfarin loading. However, low-molecular-weight heparin (LMWH) and direct oral anticoagulants (DOACs) have allowed outpatient management in selected patients. In cases of large DVT, consultation with interventional radiology or vascular surgery may be indicated for endovascular thrombectomy. Although DVTs in the calf and superficial veins of the lower extremity do not typically embolize, they can propagate into the deep venous system and may eventually lead to pulmonary emboli. Serial diagnostic studies are performed to follow the course.
Deep Venous Thrombosis. This patient has some classic findings of left lower extremity DVT: swelling, erythema, pain, and tenderness. (Photo contributor: Kevin J. Knoop, MD, MS.)
Ruptured Baker Cyst. Comparison of this patient’s ankles reveals circumferential swelling around the right side. MRI revealed a ruptured Baker cyst in the right popliteal fossa. Such a presentation may mimic acute lower extremity DVT. (Photo contributor: Lawrence B. Stack, MD.)
A Baker cyst, herniation of the synovial membrane through the posterior knee capsule, may rupture, causing unilateral calf swelling like DVT.
Patients with unexplained DVT should be screened for occult malignancy.
Homan sign (calf pain during passive dorsiflexion) is unreliable in the diagnosis.
Patients with an unclear diagnosis of cellulitis should have an objective study to rule out DVT.
The superficial femoral vein is, despite the name, a part of the deep venous system; thrombosis there requires systemic anticoagulation.
Upper Extremity DVT. Left-sided arm swelling consistent with DVT. (Photo contributor: Lawrence B. Stack, MD.)