Arterial TOS is the least common form of TOS. In fact, it is rare. However, when it occurs, it has a dramatic presentation and potentially severe complications. Patients with arterial TOS have bony anomalies more frequently than do patients with other forms of TOS. Usually, doctors diagnose these patients quickly and accurately. When arterial occlusion occurs, surgeons treat these patients urgently.
Causes of Arterial TOS
A single large subclavian artery provides almost all of the blood supply to the arm. Abnormalities of the thoracic outlet cause damage to this artery. Eventually, an aneurysm (widening) or stenosis (narrowing) of the artery may develop. Consequently, blood clot may form in the damaged artery. The blood clot may break off and block a distal artery. In that case, a patient may suffer severe pain and possible gangrene.
Symptoms of Arterial TOS
Patients usually experience sudden onset of symptoms. Specifically, pain, pulselessness, pins and needles, pale color, and coldness of the arm occur suddenly. Before this catastrophic event, patients may note tiny blood clots in the fingers, or a pulsatile painless neck mass.
Diagnosis of Arterial TOS
Arterial TOS presents in a dramatic manner. Overall, doctors make the clinical diagnosis without delay. First, your doctor will look for absent or decreased blood flow to the arm. After your doctor evaluates blood flow, she will examine the thoracic outlet for arterial compression and damage. In the case of significant arterial occlusion, your doctor will order urgent imaging tests to diagnose an arterial blood clot. After treatment of this clot, imaging tests evaluate the thoracic outlet for arterial compression, narrowing, or dilation.
Treatment of Arterial TOS
When imaging tests find arterial occlusion, the surgeon will begin urgent treatment to resolve or remove the clot. After treatment of arterial occlusion, or in cases without occlusion, the surgeon treats arterial compression or damage less urgently. Overall, treatment results are proven to be quite good if treatment begins promptly.