Iliocaval fistula with high output cardiac failure.

Fistulous communications between the common iliac arteries and inferior vena cava are very uncommon and usually occur as a result of trauma, aneurysmal rupture, or endovascular repair. They can present with signs of high output cardiac failure including hypotension, venous congestion, and pulmonary hypertension. This case outlines the utility of CTA in diagnosing iliocaval fistulas and the importance of considering this diagnosis in a patient with signs of right heart strain and high output cardiac failure.