Precise Circumflex Artery

Description

Seen from the left side of the heart, the circumflex artery courses within the left atrioventricular (coronary) sulcus, curving posteriorly between the left atrium superiorly and the left ventricle inferiorly. Proximally, it arises as a branch of the left coronary artery near the aortic root, close to the left auricle, then gives off obtuse marginal branches that descend along the obtuse (left) margin toward the ventricular myocardium. The great cardiac vein commonly parallels the artery in the same groove, and the pericardial surface landmarks frame the epicardial vessels. This lateral perspective matters because the circumflex artery is the dominant blood supply to the lateral and posterolateral left ventricular wall, and in left-dominant circulation it continues to the crux to give the posterior interventricular (posterior descending) artery. A focal stenosis here often presents as lateral wall ischemia with ST changes in leads I, aVL, V5, and V6, and it can be easy to underappreciate on limited views. Small vessel caliber changes. Those arteriole-level branches are where microvascular angina and impaired coronary flow reserve become clinically relevant despite unobstructed epicardial arteries. Use this artwork in cardiology and anatomy teaching to anchor coronary dominance, the relationship of the circumflex artery to the left atrial appendage, and the territories targeted in percutaneous coronary intervention or coronary artery bypass grafting (obtuse marginal grafts). It also fits electrophysiology and cardiac surgery references when discussing atrioventricular groove landmarks, pericardial reflections, and exposure during left atrial appendage procedures. Anatomical accuracy verified by SciePro's Medical Advisory Board.