Cath Lab Digest

Abstract

Spontaneous upper limb deep venous thrombosis (DVT) is associated with exercise and occurs in young healthy individuals. Underlying anatomical abnormalities are often found, causing compression of the subclavian vein. Prompt thrombolysis and consideration of thoracic outlet decompression differentiate it from lower limb DVT. A case illustrating the clinical features of the condition is presented here.

VASCULAR DISEASE MANAGEMENT 2010;7:E175–E177

Key words: Paget-Schröetter syndrome; deep venous thrombosis; exercise

__________________________________________________

Case Report

A 24-year-old right-handed lawyer presented with a 3-day history of painless right upper limb swelling and finger paresthesia. Six days previously, she had spent the morning clay-pigeon shooting during which she had held the stock of the shotgun against her right axilla. On examination, there was edema of the right forearm with prominent superficial veins and plethora of the fingers. There was fullness in the left posterior triangle of the neck. Adson’s test was positive bilaterally. A thrombophilia screen was negative. Thoracic radiography revealed bilateral cervical ribs (Figure 1). A duplex ultrasound confirmed occlusion of the right subclavian vein.

Venography demonstrated a short-segment subclavian occlusion with collateralization (Figure 2). This was treated with catheter-directed thrombolysis using alteplase, resulting in restoration of > 50% luminal diameter (Figure 3). The patient was anticoagulated with warfarin and experienced complete resolution of her symptoms at 3 months. Dynamic duplex imaging revealed compression of the subclavian artery and vein bilaterally. The patient returned to work and has been referred for thoracic outlet decompression. Life-long warfarin therapy was prescribed in view of the sonographic finding of bilateral subclavian vein compression.

Discussion

Spontaneous subclavian or axillary vein thrombosis (Paget-Schröetter syndrome) comprises 2% of all DVTs.1 The mean age is 30, both genders are affected equally and there is a predilection for the dominant arm.² It is often precipitated by sports involving overhead activity such as swimming and climbing, hence its alternative name “effort thrombosis.”³ In this case, there was a clear precipitant of prolonged overhead activity and trauma from elastic recoil during clay-pigeon shooting.

Whereas age and immobility are risk factors for lower limb DVT, upper limb DVT occurs in young, active patients. The mechanism is thought to be extrinsic compression of the subclavian vein within a tunnel comprising the first rib inferiorly, the subclavius muscle superiorly, the costoclavicular ligament medially and the anterior scalene muscle laterally. Abnormalities such as a laterally inserting costoclavicular ligament or cervical rib (10%) can compress the subclavian vein, predisposing to thrombosis.⁴ Complications include post-phlebitic limb syndrome from resultant valvular incompetence, venous gangrene and pulmonary embolism.⁵

Clinically, prominent superficial veins around the shoulder are often noticed (Urschel’s sign). Compressive vascular signs may be elicited with the following stress tests:

• The rowing maneuver: loss of the radial pulse as the shoulders are braced backwards. This is an alternative to Adson’s test, where the head is turned away from the affected limb and a deep inspiration results in loss of the affected radial pulse. Both of these signs have an appreciable false-positive rate.⁶

• Pemberton’s maneuver: the arms are elevated and facial plethora with distended neck veins are seen due to impeded venous return. This test is positive if the thrombus extends into the brachiocephalic vein.⁷

Thoracic radiographs may demonstrate cervical ribs or pulmonary apical lesions. Duplex ultrasound, venography or magnetic resonance imaging (MRI) are useful to detect compression of vascular structures.⁸ Duplex ultrasound has the advantage of allowing dynamic imaging while the arm is stressed, whereas MRI allows assessment of extrinsic compression.

In patients with spontaneous upper limb DVT, treatment strategies include anticoagulation, thrombolysis, venoplasty and surgical decompression. Consensus statements advocate catheter-directed thrombolysis within 5 days of symptoms.⁹ This may reveal underlying stenosis.¹⁰ However, balloon venoplasty and stenting are recognized to render poor results unless the extrinsic compression is surgically corrected.¹¹ Hence, if there is evidence of thoracic outlet compression on imaging or symptomatic venous stenosis, consensus opinion advocates thoracic outlet decompression.⁹

Results of thrombolysis and surgical decompression are encouraging in expert hands. Two large case series report > 90% symptom relief and medium-term patency.^2,12 However, the potential complication of hemorrhage from the great vessels means that first rib resection remains a specialist procedure. A review and treatment algorithm for Paget-Schröetter syndrome has recently been published.¹³ Randomized trials comparing thrombolysis and decompression with thrombolysis alone are awaited to clarify their relative benefits.

Conclusion

Physicians suspecting upper limb DVT should inquire about recent exercise. Thoracic radiography and dynamic duplex imaging are useful first-line investigations. Prompt thrombolysis and surgical decompression differentiate the management of upper limb DVT from lower limb DVT.