Anomalous mediastinal left lower lobe anterior segmental artery (A8) accidentally divided during left VATS upper lobectomy: a case report

Bronchovascular anatomical variations can pose technical challenges during lobectomy and especially segmentectomy where these structures are embedded deep in the lung parenchyma. Familiarity with these anatomical variations helps avoid intraoperative injury and accidental division. Mediastinal origin of left upper lobe apicoposterior (truncus superior) and lingula arterial branches (A4+5) is common. However mediastinal origin of left lower lobe segmental pulmonary branches is very rare and has not been reported in the literature. An anomalous mediastinal origin of left lower lobe anterior segmental artery (A8) noted during a left video -assisted thoracic surgery (VATS) upper lobectomy in a 69 years old male with stage 1 lung cancer is described. The artery was mistaken for a mediastinal lingula branch (A4+5) during surgery and was divided accidentally. The injury was recognised intraoperatively and primary end to end vascular repair was done by VATS, with the patient making an uneventful recovery. Awareness of this rare anatomical variant can help prevent intraoperative vascular injury or accidental ligation during left VATS lobectomy. Injuries due to anomalous bronchovascular anatomical variations can be prevented by preoperative planning by 3 -dimensional contrast enhanced computer tomography and by careful intraoperative dissection and identification of mediastinal and interlobar vessels distally into the respective segments before ligation.