Spontaneous aorto-caval fistulae.

The clinical and radiological presentation of four cases of spontaneous aorto-caval fistula is described. This is an unusual complication of an abdominal aortic aneurysm and presents with abdominal pain, a pulsatile abdominal mass and an abdominal bruit. Our cases illustrate the variable clinical presentation, outline the diagnostic difficulties and confirm the value of aortography. A possible role for the radiologist using a balloon catheter to close the fistula prior to surgery is suggested.