Inferior vena cava aneurysms (IVCAs) are rare yet potentially lethal, especially if they are symptomatic or complicated. Among the IVCAs reported in the literature, only a few are associated with congenital vascular anomalies, including congenital IVC obstruction, tetralogy of Fallot, left-sided IVC, duplicated IVC, Ehlers–Danlos syndrome, blue rubber bleb nevus syndrome, and Klipper-Trenaunay syndrome. We present the case of an 8-cm symptomatic saccular IVCA in a patient with tetralogy of Fallot, treated successfully with surgical repair. Although rare venous pathologies can sometimes be managed with endovascular treatment, open surgical reconstruction remains the mainstay of durable and definitive repair.