Surgical risk of vessel injury: an unusual anatomical variant of the right medial basal segmental pulmonary artery.

Video-assisted right basal segmentectomy was successfully performed on a 72-year-old man with an anomalous pulmonary artery. Multidetector row angiography showed the A7 branch arising from the right main pulmonary artery proximal to the branches of the superior trunks, lying under the middle bronchus, and reaching segment S7. Metastatic tumor (diameter 7 mm) was identified in the periphery of this vessel. This anomaly appears to be rare but seems also to be easily overlooked and could cause serious vessel injury even for video-assisted thoracoscopic right lower lobectomy.