Detection of rare variant of “circumaortic venous collar” during infrarenal abdominal aortic aneurysm repair: case report and literature review

Abstract

Congenital retroperitoneal veins anomalies (RVAs) are very infrequent, but have a relevant clinical importance in abdominal aortic surgery. We hereby present a unique case of a man with infrarenal abdominal aortic aneurysm associated with a rare anatomical variation of the left renal vein (LRV) consisting of a small ventral suprarenal and a large retroaortic vein, both draining directly into the inferior vena cava. Starting from this case we carried out an extensive literature review on clinical and surgical implications of RVAs. The retroaortic renal vein was detected preoperatively by computed tomography angiography (CTA), but the suprarenal vein was unexpected. Both infrarenal aortic clamping and aneurysm resection resulted demanding and required careful exposure of the anomalous suprarenal vein and identification of both renal arteries origin. No intraoperative bleeding or other complications occurred. The awareness and recognition of RVAs is mandatory to avoid injuries during abdominal aortic surgery.