Correction of Anomalous Origin of Right Subclavian Artery from Distal Thoracic Aorta
A fifteen-year-old girl (BMI 16.4 kg/m) with a two-year history of dysphagia, periprandial angina, and anorexia was referred to pediatric general surgery. A contrast swallow demonstrated a luminal obstruction to the esophagus, but the cause was not visible with this modality. Therefore, the patient underwent a CT scan of the thorax and abdomen, which revealed a right subclavian artery (RSA) of anomalous origin from the distal thoracic aorta (DTA). The patient was referred to pediatric cardiac surgery and consented for correction.
To begin, an anterolateral thoracotomy in the fourth intercostal space was performed. Then, the mesenchyme was dissected and the viscera mobilized until the RSA was identified and mobilized with diathermy to the surrounding connective tissue, and until the anomalous origin could be visualized at the DTA. A right-angle clamp was used to introduce a vessel loop around the RSA, which allowed for control and subsequent identification.
Next, the right jugular vein was identified in the correct anatomical position. This signified an anatomical landmark for the right carotid artery (RCA). The mesenchyme was then carefully dissected before the RCA could be visualized and mobilized. A vessel loop was introduced as previously described. A c-clamp was used to temporarily divide a sagittal section of the RCA wall; this is the anastomotic site. The site was then tested for robustness and durability and the clamp was removed.
After this, the RSA was clamped using a right-angle at the anomalous origin. A transecting incision was made to the RSA distal to the clamp, and the remaining stump at the origin was oversewn using 6-0 Prolene. Before removing the clamp, the surgeon had to ensure that any anastomotic leak had been addressed and that full hemostasis had been achieved. This is because the stump moves medially upon declamping, and any subsequent bleeding would be difficulty to localize and control. The arterial pressure of the right upper limb significantly deteriorated upon clamping of the RSA, suggesting anastomosis of the RSA to the RCA was indicated.
Finally, a c-clamp was reapplied to the anastomotic site of the RCA. The free RSA was then grafted onto the RCA in end-to-side anastomosis using a 6-0 Prolene. After checking for anastomotic leak and achieving hemostasis, the c-clamp was removed and the anastomosis was functional. The arterial pressure in the right upper limb normalized.
The patient was then closed and transferred to ICU before being discharged following convalescence. They remain asymptomatic.