Duplication of the Superior Vena Cava - Occasional Finding or Genetic Disorder?

Case report: 17-year-old-male with dysmorphic features (high forehead, hypotelorism, small eye opening, large nose with septal deviation, micrognathia, dysplastic and displaced ears, pectus excavatum, wide interphalangeal joints), phenotypically similar to his father. Regarding the genetic study, the karyotype and array analysis were normal and no TRPS1 gene alterations were found. Currently waiting for the NGS/exome panel.

He was hospitalized for presenting weekly syncope episodes at rest, preceded by dizziness and skin pallor, during the previous two months. These episodes of lost consciousness lasted between 1-2 minutes, were associated with sialorrhea, resolved spontaneously and were followed by chest pain. No sphincter incontinence, posterior hypersolence or constitutional symptoms were present. There were no apparent abnormalities on the x-rays and urine drug screening was negative. Chest computed tomography (CT) angiography showed superior vena cava duplication and left internal jugular vein drainage directly into the left atrium. ECG featured sinus arrhythmia and the echocardiogram revealed no other changes, as did the valve flows Doppler and Holter. Carotid artery ultrasound, EEG and cranial CT were normal. The diagnosis of generalized anxiety disorder was proposed and after treatment with sertraline was initiated there was a decrease in frequency of such episodes.

Discussion: This case report raises several questions: Is there a relationship between the phenotypic changes, the described episodes and/or the superior vena cava duplication? Can we assume that these episodes are related to an anxiety disorder?
Is duplication of the superior vena cava a finding or the cause of the symptoms? Will the study of the father be advantageous? It is the authors purpose to emphasize that pluridisciplinarity and clinical knowledge sharing in this case is crucial given the scarcity of bibliography.