Small cardiac vein
# Small cardiac vein

The small cardiac vein, also known as the right coronary vein, is a coronary vein that drains parts of the right atrium and right ventricle of the heart. Despite its size, it is one of the major drainage vessels for the heart.

## Anatomy

### Course

The small cardiac vein runs in the coronary sulcus between the right atrium and right ventricle, and opens into the right extremity of the coronary sinus.

### Territory

The small cardiac vein receives blood from the posterior portion of the right atrium and ventricle.

### Variation

The small cardiac vein may empty into the coronary sinus, right atrium, or middle cardiac vein. It may be absent.

