Anterior cardiac veins

The anterior cardiac veins are a group of small veins that primarily drain the anterior regions of the right ventricle and the right cardiac border, emptying directly into the right atrium rather than into the coronary sinus. They represent one of the three major systems of cardiac venous drainage, alongside the coronary sinus tributaries and the Thebesian veins.

These veins are anatomically distinct from the coronary sinus system. While the coronary sinus and its tributaries drain most of the left ventricle and posterior heart, the anterior cardiac veins provide an independent drainage pathway for the right ventricular myocardium. The number and configuration of anterior cardiac veins are highly variable between individuals. In some cases, the right marginal vein (which might otherwise drain into the coronary sinus as the small cardiac vein) instead joins the anterior cardiac vein system—this occurs in approximately 64% of hearts, which significantly increases the functional importance of the anterior cardiac venous drainage.

The anterior cardiac veins typically open into the right atrium through intramural venous sinuses, which are small collecting chambers in the atrial wall that facilitate venous return.