Ruptured Abdominal Aortic Aneurysm with a Duplicated Inferior Vena Cava

We report a very rare case of a ruptured abdominal aortic aneurysm (AAA) with an anomaly of the inferior vena cava (IVC). The AAA was covered with a large hematoma and an expanded vein was on its left side. It was not until we could not locate the IVC on the right side of AAA that we recognized the anomaly during the operation. Although we reviewed the findings on enhanced computed tomography, we were confused whether the case was a duplicated or left-sided IVC. Subsequently, a bifurcated vascular prosthesis was implanted without ligation of the left renal vein to join the left-sided IVC.