Left coronary aortic sinus

The left coronary aortic sinus (Left sinus of Vasalva) is one of the three aortic sinuses located at the root of the ascending aorta, just above the left cusp of the aortic valve. It gives rise to the left main coronary artery, which emerges from the left coronary sinus and then bifurcates into the left anterior descending (LAD) and circumflex (LCx) coronary arteries.

The left coronary sinus is bordered by the right and non-coronary aortic sinuses. It is located posteriorly and to the left in relation to the aortic root.

The left coronary sinus should not be confused with the term "coronary sinus", which is a venous structure located in the posterior atrioventricular groove.The right coronary sinus is a component of the aortic root and does not have direct venous drainage or a role in the coronary venous system.