Double inferior vena cava with variant hemiazygos vein – a case report

Abstract

The duplication of the inferior vena cava is a rare variation resulting from an alteration in the embryogenesis of the cardinal venous system. Although there are various types of double inferior vena cava and is prevalent in 2-3% of the population, the continuation of left inferior vena cava as hemiazygos vein is a very unusual variant and hence this case is reported for its rarity and clinical significance. During dissection of an eighty-seven-year-old female cadaver, the presence of the double inferior vena cava was noted. A detailed dissection was done of the major veins of the abdomen and traced till their drainage into the thorax. The right and left inferior vena cava were connected by a venous bridge which coursed deep to the abdominal aorta. The right inferior vena cava followed its usual course and drained into the right atrium, while the left inferior vena cava entered the thoracic cavity as the hemiazygos vein and drained into the azygos vein. Anatomical knowledge of the rare variant prevents misdiagnosis and aids in the proper interpretation of radiological images. Also, awareness of this vascular anomaly guides the surgeons during retroperitoneal procedures when encountering intraoperative difficulties.