Coronary Arteries and Cardiac Veins
|STERNOCOSTAL AND DIAPHRAGMATIC SURFACES|
The normal heart and the proximal portions of the great vessels receive their blood supply from two coronary arteries. The left coronary artery (LCA) originates from the left sinus of Valsalva near its upper border, at about the level of the free edge of the valve cusp. The LCA usually has a short (0.5-2 cm) common stem that bifurcates or trifurcates. One branch, the anterior inter- ventricular (descending) branch, courses downward in the anterior interventricular groove (largely embedded in fat), rounds the acute margin of the heart just to the right of the apex, and ascends a short distance up the posterior interventricular groove.