Case Presentation:
A 17‐year‐old white female presented to the ER with a 5‐day history of right upper extremity swelling. The patient reported that she carried a heavy book bag on her right shoulder all day, followed by 1 hour of using her arms over her head while styling her hair. The next morning, she developed pain and swelling in her right arm. Physical examination revealed right upper extremity swelling with mild erythema. Duplex ultrasound demonstrated no obvious filling defect; however, there was an absence of flow in the subclavian and axillary veins, suggesting upstream thrombus. MRI of the chest and right upper extremity found an occluded right subclavian vein by thrombus. The patient was subsequently treated with mechanical thrombectomy and catheter‐directed thrombolysis with tPA. A hypercoagulable workup was unremarkable. She was continued on warfarin anticoagulation for 6 months without sequelae.
Discussion:
Primary (ie, not catheter‐related) upper extremity deep venous thrombosis (UEDVT) is an uncommon disorder with an incidence of 2 per 100,000 yearly. Primary UEDVT can be divided into effort thrombosis (Paget‐Schroetter syndrome), hypercoagulable, and idiopathic. Effort thrombosis is typically seen in a patient's dominant arm after particularly strenuous activity. The underlying pathophysiology of effort thrombosis is related to microtrauma in the vessel and mechanical obstruction/compression by thoracic outlet syndrome, muscle hypertrophy, cervical ribs, clavicular or first rib abnormalities, or a long transverse process of the cervical vertebrae. Many cases that were once relegated to “idiopathic” status are commonly associated with a hypercoagulable state. In 1 study evaluating patients with a primary UEDVT, 61% were noted to have at least 1 coagulation abnormality; the most common abnormalities were anti‐phospholipid antibodies (44%), factor V Leiden (13%), prothrombin G20210A (20%), elevated homocysteine (16%), and protein S deficiency (5%). Duplex ultrasound is the initial test of choice, but it must be remembered that false‐negatives can occur because of shadows from the clavicle. Studies of duplex ultrasound report a sensitivity ranging from 56% to 100% and a specificity of 94%‐100% in the upper extremities. The current therapeutic standard is warfarin anticoagulation for 6 months. For younger or more active patients, thrombolysis to reduce the long‐term risk of postthrombotic syndrome may be considered. If radiographic anatomic anomalies exist, most vascular surgeons are in favor of early correction of the abnormality.
Conclusions:
Although an uncommon disorder, UEDVT requires a thorough evaluation by hospitalists. If duplex ultrasound is nondiagnostic, further imaging should be performed. Care should be taken to rule out any skeletal anomalies with radiographs. Patients should undergo a thorough hypercoagulable workup. Finally, thrombolysis in younger, active patients should be considered to prevent postthrombotic syndrome.
Author Disclosure:
S. R. Sommers, none; B. A. Khan, none.