44 - Coronary sinus

*The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the myocardium of the heart.
*It is present in humans and other animals.
*The coronary sinus opens into the auricle, between the inferior vena cava and the auriculo-ventricular opening.
*It returns the blood from the substance of the heart, and is protected by a