Posterior view of arteries and veins of the heart and lungs
The coronary sinus is clearly visible, as the largest vein on the body of the heart. “Coronary” means “crown”, so if one thinks of the heart as a head, anything labeled “coronary” likely goes around it in a somewhat-encircling fashion.
The anterior cardiac veins drain directly into the right atrium, but the majority of the other cardiac veins (excluding some of the smallest), including the great cardiac vein, drain into the coronary sinus. The junction between the right atrium and the coronary sinus is marked by the Thesbian valve.
Traité complet de l’anatomie de l’homme comprenant la medecine operatoire, par le docteur Marc Jean Bourgery. Illustration by Nicolas Henri Jacob, 1831.