great coronary (cardiac) vein (coming from the anterior side of heart) |  middle cardiac veinsmall cardiac vein coming from the right anterior of myocardium  | together the preceding merge to become the  coronary sinus, which leads into the right atrium   |  inferior vena cava   | circumflex artery (coming from anterior left side) |  posterior interventricular artery, a branch of the right coronary artery | left atrium  |  left pulmonary veins |