Coronary Circulation

The myocardium has its own network of blood vessels, separate from the systemic and pulmonary circuits, called the coronary circulation.

The left and right coronary arteries originate from the ascending aorta, supplying oxygenated blood to the myocardium.

The left coronary artery divides into the left anterior descending artery or LAD, supplying blood to the ventricular walls, and the circumflex artery, supplying blood to the left atrial and ventricular walls.

The right coronary artery supplies blood to the right atrium. It further branches into the posterior descending artery or PDA, serving the ventricular walls, and the marginal branch, serving the right ventricle.

Anastomoses link different coronary arteries, providing alternate routes for blood supply when arteries are blocked.

The coronary sinus, a large vein fed by many small ones, transports deoxygenated blood to the right atrium.

The great and middle cardiac veins drain the area supplied by the LAD and PDA, respectively.

The small cardiac vein collects blood from the right atrium and ventricle.

Collecting blood from the right ventricle, the anterior cardiac vein empties directly into the right atrium.