title: A rare variant between the left superior vena cava and the azygos vein.
abstract: During the educational dissection of a 68-year-old Chinese male cadaver, an azygos vein (AV) coursing on the left side with double superior vena cava was observed. The left superior vena cava (LSVC) began from the confluence of the left internal jugular and left subclavian veins, and extended downwards medially into the left edge of the dilated coronary sinus. The right superior vena cava was formed by the union of the right internal jugular and right subclavian veins, and drained into the right atrium from the above. The AV was formed by the union of the right and left ascending lumbar veins at the level of the tenth thoracic vertebra. It ascended along the left margin of the thoracic vertebra, receiving almost the bilateral posterior intercostal veins and then extended into the LSVC on the left wall via the azygos arch. Better understanding of these variations will reduce unnecessary and potential harmful testing, and unneeded patient anxiety.
authors.affiliation: Department of Anatomy, Academy of Basic Medicine, Jining Medical University, Jining, 272067, Shandong, China. alexlijing800912@yahoo.com.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Neonatal Intensive Care Unit, First People's Hospital, Jining, 272000, Shandong, China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Mao
authors.affiliation: Department of Medical Image, Affiliated Hospital of Jining Medical University, Jining, 272000, Shandong, China.
authors.forename: Zhanguo
authors.initials: Z
authors.lastname: Sun
authors.affiliation: Department of Cardiac Surgery, Affiliated Hospital of Jining Medical University, Jining, 272000, Shandong, China.
authors.forename: Qingchen
authors.initials: Q
authors.lastname: Li
mesh_terms: D000368:Aged; D063405:Anatomic Variation; D001401:Azygos Vein / Q000002:abnormalities* / Q000033:anatomy & histology; D002102:Cadaver; D004210:Dissection; D006801:Humans; D007601:Jugular Veins / Q000002:abnormalities* / Q000033:anatomy & histology; D008297:Male; D008482:Mediastinum / Q000098:blood supply; D013350:Subclavian Vein / Q000002:abnormalities* / Q000033:anatomy & histology; D014683:Vena Cava, Superior / Q000002:abnormalities* / Q000033:anatomy & histology
keywords: Anatomical variation; Azygos vein; Double superior vena cava