Spontaneous aorto-caval fistulas from ruptured abdominal aortic aneurysms.

Thirty-six cases of abdominal aortic aneurysms rupturing into the vena cava and two iliac aneurysms rupturing into iliac veins are reported. This group represents 10% of the total number of observed ruptured abdominal aortic aneurysms (388). Such a condition is therefore quite rare but should be considered positively because the reported mortality rate is less than with ruptured aneurysms in general. Nevertheless, a spontaneous aorto-caval fistula is responsible for a critical haemodynamic deterioration and sudden worsening of the general condition of the patient and therefore prompt surgical repair is mandatory. The overall mortality rate in our series was 21% (8 cases).