Superior Segmental Artery of the Left Lung

Description

Arising from the left pulmonary artery, the superior segmental artery (A6) courses laterally and posteriorly toward the superior segment of the left lower lobe. Along its upward trajectory it travels close to the left main bronchus and lower lobe bronchus, with the segmental bronchus (B6) typically positioned posterolateral to the corresponding arterial branch. Proximally, the vessel sits inferior to the aortic arch and left pulmonary artery bifurcation, while mediastinal landmarks such as the trachea and main bronchi provide superior orientation. Segmental pulmonary arterial anatomy is the map surgeons and interventionalists use when an operation must stop at a segment boundary rather than a lobe. A6 is a frequent target in left lower lobe superior segmentectomy for small peripheral non small cell lung cancers and in treatment planning for localized bronchiectasis, because controlling this artery early limits bleeding and helps define the intersegmental plane. It is also a vessel radiologists track on CT pulmonary angiography when segmental pulmonary embolus is suspected, since thrombus at the segmental level can produce wedge shaped infarction in the dependent posterior lung. Use this illustration in thoracic surgery teaching files to support stepwise hilar dissection (artery, bronchus, vein) and in radiology or anatomy coursework focused on pulmonary segmental nomenclature and bronchovascular pairing. It also fits cardiopulmonary chapters in medical textbooks where the pulmonary trunk, right and left pulmonary arteries, and their lobar and segmental branches need a clear, labeled reference. Anatomical accuracy verified by SciePro's Medical Advisory Board.