Unique Medley of Cardinal Veins: Duplicated Superior and Inferior Venae Cavae With Left Renal Agenesis and Hemiazygos Continuation of Left Inferior Vena Cava With Drainage Into Left Atrium

Congenital anomalies of the superior and inferior vena cava result from abnormal embryogenesis of cardinal veins. Duplication of superior vena cava (SVC) occurs in 0.3% of the general population of which only 8% drain into the left atrium. The prevalence of double inferior vena cava (IVC) is around 0.2–3%. The reported incidence of unilateral renal agenesis ranges from 1:1100 to 1:5000, and the association of double IVC with renal agenesis has been reported in only 11 cases in the literature. The conglomeration of such rare anomalies incidentally noted in a single patient is reported in this study. A 32-year-old man was referred to our department for Computed Tomography (CT) scan of the thorax. The patient was found to have dorsal kyphoscoliosis with hemivertebrae. The SVC was duplicated with the right SVC draining into the right atrium and the left SVC draining into the left atrium. The left kidney was not visualized in the abdomen. There was dual IVC with no intercommunicating interiliac vein. The right IVC maintained its normal course, while the left IVC continued as hemiazygos vein and joined left SVC in the thorax. Also noted was the aberrant origin of the right subclavian artery. This is the first reported case of combined superior and inferior vena caval anomalies along with left renal agenesis in a single patient in the literature. A review on the embryological basis is also described in this article.