A Cadaveric Study of Double Superior Vena Cava with Paired Azygos Vein & its Clinical Implications

Author: Sabita Singh , Parineeta Suman , A.David Ebenezer

Category: Anatomy

Abstract:

Introduction: Double superior vena cava with a Persistent Left Superior Vena Cava (PLSVC) is an uncommon abnormality but is the most common thoracic venous anomaly in the setting of SVC. It is estimated to occur in 0.3- 0.5% of the general population and 3-10% of patients with other forms of congenital heart disease. The present study aimed to find the frequency of double superior vena cava, its embryological basis and to correlate its clinical significance.

Materials and methods: The present study, a descriptive study includes sixty cadavers allotted for first year MBBS students in Department of Anatomy at Velammal Medical College, Madurai during year 2013-2018. Superior vena cava along with other veins had been traced and studied in detail.

Results : Double superior vena cava was found in 2 cadavers out of 60 cadavers (3.33%). Persistent left superior vena cava opened into an enlarged coronary sinus that further drained into the right atrium in both the cases. Left brachiocephalic vein was present in one of them and left azygos vein ran upward along the left side of vertebral column and drained into PLSVC in the cadaver. There was no anastomosis between azygos and hemiazygos vein.

Conclusion : Persistent left superior vena cava (PLSVC) occurs as a result of failure of regression of left anterior cardinal and left common cardinal veins. The precise knowledge of double superior vena cava by surgeons, sonographers and interventional radiologists can prevent possible complications in routine clinical practice and during cardiopulmonary bypass.

Keywords: Double superior vena cava, Persistent left superior vena cava, Left azygos vein, Anterior cardinal vein, Coronary sinus