What is the main vein that drains blood from the heart?

The coronary sinus is the principal and largest vein of the heart. It lies in the posterior atrioventricular groove and drains most venous blood from the myocardium into the right atrium.

Which veins drain directly into the right atrium without going through the coronary sinus?

The anterior cardiac veins and venae cordis minimae (Thebesian veins) bypass the coronary sinus. Anterior cardiac veins drain the anterior right ventricle, while Thebesian veins are minute veins that open directly into all heart chambers.

What are the tributaries of the coronary sinus?

The coronary sinus receives blood from tributaries such as the great cardiac vein, middle cardiac vein, small cardiac vein, posterior vein of the left ventricle, oblique vein of the left atrium (vein of Marshall), and right and left marginal veins.

Where is the coronary sinus located in the heart?

The coronary sinus is located in the posterior part of the atrioventricular groove (also called the left posterior coronary sulcus). This position allows it to collect venous blood efficiently before draining into the right atrium.

What is the function of the venae cordis minimae (Thebesian veins)?

The venae cordis minimae (Thebesian veins) are minute veins that drain blood directly from the myocardium into the heart chambers. They are found in all four chambers, with the greatest number in the right atrium, providing an alternative drainage pathway.

How does the venous drainage of the heart relate to its arterial supply?

Venous drainage and arterial supply are complementary systems. Many cardiac veins, like the great cardiac vein and middle cardiac vein, accompany corresponding arteries (e.g., anterior interventricular and posterior interventricular arteries) to efficiently remove deoxygenated blood after myocardial perfusion.

Heart Venous Drainage – Coronary Sinus & Tributaries