Causes of the fistula:
(1) rupture of an aortic or iliac aneurysm
(1a) atherosclerotic aortic aneurysm
(1b) mycotic aneurysm
(1c) aneurysm in a patient with a connective tissue disorder (Ehlers- Danlos, Marfan's)
(2) iatrogenic
(2a) after lumbar disc surgery
(2b) after repair of an abdominal aortic aneurysm
(3) penetrating wound
(3a) gunshot wound
(3b) knife wound
(4) rarely associated with a malignant tumor
(5) rarely blunt trauma
Signs and symptoms:
(1) high output heart failure with dyspnea
(2) wide pulse pressure
(3) edema of legs
(4) distention of leg veins which may be pulsatile
(5) decreased pulses in the lower extremities
(6) abdominal or back pain
(7) bruit over the abdomen
(8) pulsatile abdominal mass
(9) hematuria and rectal bleeding
(10) oliguric renal failure
(11) pulmonary emboli
(12) hypotension
(13) tachycardia (bradycardia rare)
Imaging studies will usually show the fistula unless it is occluded by thrombus.