Coronary sinus

The coronary sinus (CS) is a venous channel in the posterior atrioventricular groove, draining most of the cardiac veins into the right atrium, with important anatomical relationships to the mitral valve annulus, left atrium, and adjacent coronary arteries, and is frequently guarded by the valve of Thebesius.

It is located in the posterior part of the coronary sulcus, between the left atrium and left ventricle. It opens into the right atrium between the inferior vena cava and the tricuspid valve, often guarded by the Thebesian valve.

The tributaries of the coronary sinus are great cardiac vein (GCV), inferior vein of left ventricle, oblique vein of left atrium, middle cardiac vein (MCV), and small cardiac vein (SCV).

The great cardiac vein transitions into the coronary sinus as it curves to the left, forms the base of the triangle of "Brocq and Mouchet" with the branches of the left coronary artery.

The coronary sinus typically measures around 39.73 ± 16.9 mm in length and has an average diameter of 9.81 ± 9.3 mm.