Great cardiac vein

The great cardiac vein (GCV) runs in the anterior interventricular groove and drains the anterior aspect of the heart where it is the venous complement of the left anterior descending artery. It is the main tributary of the coronary sinus. 

Gross anatomy

It begins on the anterior surface of the heart near the apex where small tributaries of the great cardiac vein anastomose with tributaries of the middle cardiac vein. It ascends in the anterior interventricular groove with the left anterior descending artery. At the coronary sulcus it turns left, to runs alongside the circumflex artery in the left atrioventricular groove to drain into the left end (origin) of the coronary sinus,  at the same end as the oblique vein of Marshall which together marks the origin of the coronary sinus.

Relations

The relationship of the great cardiac vein to the left anterior descending artery is highly variable. In 60-70% of cases, the vein is superficial to the artery.

Drainage

The vein drains the:

• anterior surface of the right and left ventricles (up to and including the apex)
• anterior interventricular septum
• portions of the left atrium

Variant anatomy

• the vein may drain directly into the right atrium or azygous vein
• there may be aneurysmal dilatation of the great cardiac vein 
  • occurs in ~1.5% of cardiac CT studies, second most common coronary vein aneurysm

Knowledge of variants may be useful for preoperative planning.

Fun fact

As the great cardiac vein turns left at the coronary sulcus, it runs adjacent to the LCx with blood in each vessel flowing in the same direction, which is, to say the least, peculiar!