The sub-renal abnormalities of the lower vena cava (LVC) (left LVC, double LVC) are determined by a deterioration of the alteration process of supra-cardinal veins. Though they are rare, it is necessary to look for them during surgery of abdominal aorta in order to lower the risk of iatrogenic venous injuries. You will find below the description of six cases of sub-renal lower vena cava abnormality (3 double LVC, 3 left LVC) associated with an abdominal aorta aneurism (4 non specific aneurisms, 2 inflammations ones) as well as the diagnostic aspects and the technical issues they cause during the reconstruction of a non specific and inflammation aneurism of the abdominal aorta.