Right top pulmonary vein is a venous anomaly of which surgeons should be aware in subcarinal dissection for thoracoscopic esophagectomy: a case report and literature review

A right top pulmonary vein (RTPV) that crosses behind the right main or intermediate bronchus is a variation of the superior posterior pulmonary vein in the right upper lobe. Damage or ligation of this abnormal vessel can lead to massive intraoperative bleeding and serious complications, such as congestion of the posterior segment of the right upper lobe and cardiac tamponade. Subcarinal lymph node dissection is mandatory in radical thoracoscopic esophagectomy for esophageal cancer, and the RTPV is an anomalous vessel of which thoracic surgeons should be aware. A 70-year-old man underwent thoracoscopic esophagectomy for esophageal cancer (T3N1M0). An anomaly of the superior posterior pulmonary vein in the right lobe was recognized on preoperative computed tomography imaging. With simulation and intraoperative navigation using three-dimensional imaging of the same view as that observed during the operation, radical subcarinal dissection could be performed with preservation of the RTPV. In our review of the relevant literature, the incidence of RTPV ranged from 0.28 to 9.3%, and its mean vascular diameter was 7.0 mm at the maximum and 2.2 ± 0.72 mm at the minimum, with the right superior pulmonary vein being a relatively common inflow site. Our case in which the RTPV ran dorsal to the right main bronchus is very rare. In radical subcarinal dissection of thoracoscopic esophagectomy, it is important to recognize the posterior pericardial plane and release the ventral fixation of these lymph nodes to free space for the back side. This is also true in the case of RTPV, which should be noted to avoid injury. In cases involving an RTPV larger than 4.5 mm, ligation should be avoided, and preoperative recognition of the exact run of this abnormal vessel using three-dimensional imaging can be very useful.