Great cardiac v.

The great cardiac vein (left coronary vein) begins at the apex of the heart and ascends along the anterior interventricular sulcus to the base of the ventricles. It then curves to the left in the coronary sulcus and passes around to the posterior surface of the heart. There, it opens into the left extremity of the coronary sinus.

It receives tributaries from the left atrium and from both ventricles. One of these, the left marginal vein, is of considerable size and ascends along the left margin of the heart.