Atlas of Human Anatomy by Netter

The coronary sinus is a wide vein that runs transversely across the posterior surface of the heart in the coronary groove.

The coronary sinus receives blood from

The great cardiac vein that ascends in the anterior interventricular groove and enters the coronary sinus at its left end

The middle cardiac vein (posterior interventricular vein) that ascends in the posterior interventricular groove and enters the coronary

sinus at its right end

Small cardiac veins

Left marginal vein

Left posterior ventricular vein(s)

Anterior cardiac veins that enter the right atrium directly

Venae cordial minimae (smallest cardiac veins) that open directly into the chambers of the heart

Innervation and Conducting System of the Heart

[Plate 216, Valves and Fibrous Skeleton of Heart]