An unusual pulmonary vascular connection encountered during right upper lobectomy

Pulmonary vascular variations may complicate thoracic surgery, particularly video-assisted procedures where such anomalies increase the risk of bleeding. We report a 77-year-old female undergoing right upper lobectomy for invasive mucinous adenocarcinoma. Imaging revealed a 2 cm posterior right upper lobe nodule with low FDG uptake. Histology showed mixed adenocarcinoma and large-cell neuroendocrine carcinoma (Stage IA). Intraoperatively, a vascular connection consistent with an arteriovenous fistula between the superior pulmonary vein and interlobar pulmonary artery was identified and ligated.