Coronary veins

The coronary veins return deoxygenated blood from the myocardium back to the right atrium. Most venous blood returns via the coronary sinus. Coronary venous anatomy is highly variable, but is generally comprised of 3 groups of veins:

• cardiac veins which drain into the coronary sinus:
  • great cardiac vein
  • middle cardiac vein
  • small cardiac vein
  • posterior vein of the left ventricle
  • vein of Marshall (oblique vein of the left atrium)
• the anterior cardiac veins which drain directly into the right atrium
• the venae cordis minimae (smallest cardiac veins or the thebesian veins) which also drain directly into the right atrium