A 34-year-old male motor mechanic was admitted with a 3-day history of severe swelling of the right arm. He had been undertaking physical activity, including weightlifting, training for about 1.5 h four times a week. There was no history of trauma. The patient felt discomfort, but no severe pain in the arm. The superficial veins were distended. The color of the hand and forearm was slightly cyanotic. The pulses in the radial and ulnar arteries were palpable. No bruits could be heard along the brachial, supraclavicular or axillary arteries. The rest of the examination was without remarks. The patient did not use any medication.

Question 1

What further diagnostic investigations would you prefer in this patient?

A.  Pletysmography

B.  Venography C.  Duplex scanning

D.  Magnetic resonance phlebography E.  Computed tomography (CT) scanning F.  X-ray of the chest and thoracic outlet G.  Venous pressure measurements

Venography revealed a thrombosis of the axillary/subclavian veins (Fig. 37.1). The brachiocophalic vein was patent. There were no signs of skeletal deformities.

T. Dahl ( )

Department of Surgery, St. Olavs Hospital, University Hospital of Trondheim, Trondheim,

Norway

A.  10%

B.  25%

C.  40%

D.  60%

E.  80%

Question 5

A control venography revealed a stenosis of the axillary/subclavian vein at the thoracic outlet. There was no residual thrombotic material. At 3 months’ follow-up the patient still had pain and discomfort in the arm when going back to his job as a motor mechanic. Which of the following alternatives of treatment would you recommend at this stage?

A.  Repeated attempt of thrombolytic therapy

B.  Balloon angioplasty and stenting of the subclavian artery C.  Continued oral anticoagulation therapy

D.  Relief of the thoracic outlet by resection of the first rib including venolysis E.  Direct reconstruction of the vein

37.1  Commentary

In patients with acute axillary/subclavian vein thrombosis, it is important to separate so-called primary from secondary thrombosis. Primary thrombosis is also known as Paget–Schroetter’s syndrome, which is induced by strenuous activity of the arm or venous compression at the thoracic outlet predisposing for thrombosis formation.1–4 The term “effort thrombosis” is also used for this condition. Men are affected more often than women, and the incidence is higher in the veins of the dominant arm. Secondary axillary/subclavian vein thrombosis could be caused by venous-access catheters, pacemaker wires, malignancies, radiotherapy or compression from local tumor formation. Secondary thrombosis is also seen as a complication of thrombophiliaandinpatientswithdialysisfistulas.5 [Q2:A,B,C,D,E]Thepreferredtherapy may be different in the two groups, and in general a more conservative attitude is justified in patients with secondary thrombosis. These patients often have a limited life expectancy due to serious comobidities, such as cardiac disease or malignancy, which would also represent a contraindication to thrombolytic therapy. In addition, there is often less need for extensive activity of the upper extremities in this group of patients. There is usually a rich venous collateral network, and therefore phlegmasia coerulea dolens of the arm is extremely rare. It may occasionally be connected with hypercoagulability or malignancies.

Complications following axillary/subclavian vein thrombosis are swelling, pain and discomfort in the arm prohibiting work or daily-life activities. Furthermore, it has been reported that up to ten per cent of the patients with axillary/subclavian vein thrombosis develop pulmonary emboli and that it is more common than usually appreciated.5,6

In patients with primary axillary/subclavian vein thrombosis, duplex scanning can be performed as a supplement to the clinical examination.6 However, duplex scanning is operator

dependent. If the examination is negative, then venography has to be performed anyway. Three-dimensional gadolinium-enhanced magnetic resonance phlebography technique has been applied successfully.7 However, venography, preferably by contrast injection via the basilicvein,isstillthegoldstandardinthesecases.Theguide-wirecouldbeadvancedintothe thrombustoinvestigateifitissoftenoughforlysis.AchestX-rayincludingthethoracicoutlet to investigate the possibility of bony deformation is also indicated. [Q1: B, C, F]

D-dimer levels are usually elevated in patients with thrombus. The patient should also be evaluated thoroughly for thrombophilia and blood tests should include a blood count, tests for decreased levels of anti-thrombin (III), protein C and protein S deficiencies, activated protein C (APC) resistance, antiphospholipid antibodies (lupus anticoagulans) and anticardiolipin antibodies. Contraceptive drugs can cause axillary subclavian vein thrombosis due to a decrease in the anti-thrombin levels.

As soon as the diagnosis has been established, systemic heparinisation is administered.8 This should be followed by local thrombolysis using recombinant tissue plasminogen activator (rt-PA) unless there are contraindications.9–14 [Q3: D, E] At introduction of the guidewire, the resistance will indicate the age of the thrombosis and the possibility of obtaining lysis of the thrombotic occlusion. The catheter for application of the thrombolytic agent should be placed within the thrombosis. Usually, a dose of 5 mg rt-PA is given as a bolus, followed by infusion of 0.01 mg/kg body weight/h for 24–72 h.

Although the most favorable results are obtained in patients with less than 1 week’s durationofsymptoms,10 anattemptatthrombolysiscouldbejustifiedevenifthesymptoms have lasted for 1 month. [Q4: E]

Afterthrombolysis,arepeatvenographyisperformedtoevaluatewhetheranyintrinsicor extrinsic obstructions of the blood flow are present. Often a defect is located close to the costoclavicular ligament. Together with hypertrophic anterior scalene and subclavius muscles, this ligament could cause external compression of the vein. Intrinsic venous stenosis is thought to be due to repetitive trauma damaging venous valves or the endothelium, or producing thickening of the vein wall or intraluminal synechiae, predisposing to thrombosis.

After thrombolysis the patient should be on oral anticoagulation for 1–3 months, depending on the preferred time for thoracic outlet decompression. Some centers proceed with more radical surgery soon after thrombolysis.11,15,16 By allowing a 3 month period of oral anticoagulation,the clinical status could be reevaluated. If the patient is asymptomatic at follow-up, we do not recommend further treatment.13

If the patient is symptomatic and there is a residual stenosis of the subclavian vein caused by either internal or external pathological structures, then the stenosis should not be treated by balloon angioplasty or stenting primarily.11–13,15,17 Whenever these treatment modalities are applied before relief of the thoracic outlet, recurrence of the symptoms will inevitably occur. Furthermore, fracture of the stents has been described because of the “scissors effect” caused bythenarrowthoracicoutlet.18 Decompressionofthethoracicoutletisobtainedbyresectionof the first rib, including the distal part of the anterior and middle scalene muscles and fibrous structures adhering to the first rib. Venolysis is also a part of the procedure. [Q5: D]

The surgical approach for relieving the thoracic outlet is controversial: However, most surgeons prefer a transaxillary approach. In cases where reconstruction of the vein is indicated a paraclavicular approach can be used.3,5,11,15,16,19,20 After thoracic outlet surgery, a venous obstruction can be treated with balloon angioplasty preferably without stenting. Finally, in rare cases, direct reconstruction by endovenectomy and patch angioplasty may be indicated for relief of intravenous obstructions.3