Spontaneous idiopathic subclavian arteriovenous fistula: a case report.

Systemic arteriovenous (AV) fistulas are a rare but correctable cause of hyperkinetic circulation and congestive heart failure. They are generally due to catheterization procedures, surgery, trauma, or aneurysms. A case of truly spontaneous AV fistula between left subclavian artery and left innominate vein is described. This patient presented with symptoms that might clinically be mistaken for a carpal tunnel syndrome. The discovery of a continuous to-and-fro murmur on her left upper sternal border led to the correct diagnosis. Surgical ligature of the fistula provided complete relief of the woman's symptoms.