A 68-year-old man with a right common iliac artery aneurysm perforating the inferior vena cava showed cardiomegaly and pulmonary congestion with left leg edema and dyspnea on exertion. The patient demonstrated a hyperdynamic circulation characterized by increased filling pressure, low systemic resistance, and high cardiac output (9.81l/min/m²) before surgery with a pulmonary-to-systemic blood flow ratio of 1.36. At operation, the right iliac artery to the inferior vena cava fistula, 5×10mm across, was closed along with resection and replacement of the aneurysm with a woven dacron graft of 10mm in diameter. The procedure caused acute and dramatic changes both in pre- and after-loads associated with aortic clamping as well as with elimination of A-V shunt through the fistula. Diligent attention was required both by surgeons and anesthesiologists to cope with these rather dramatic hemodynamic shifts during and after surgery. The patient did well and was discharged with normal hemodynamic parameters.