Location:
The right coronary artery emerges from the aorta into the AV groove. It descends through the groove, then curves posteriorly, and makes a bend at the crux of the heart and continues downward in the posterior interventricular sulcus. Within millimeters after emerging from the aorta, the right coronary artery gives off two branches: 1) the conus (arteriosus) artery which runs to the right ventricular outflow tract, and 2) the atrial branch which gives off the SA nodal artery (in ~ 50-73% of hearts), which runs along the anterior right atrium to the superior vena cava, encircling it before reaching the SA node. The right coronary artery continues in the AV groove and gives off a variable number of branches to the right atrium and right ventricle. The most prominent of these is the right marginal branch which runs down the right margin of the heart supplying this part of the right ventricle. As the right coronary curves posteriorly and descends downward on the posterior surface of the heart, it gives off two to three branches. The AV nodal artery which branches from the right coronary artery at the crux of the heart and passes anteriorly along the base of the atrial septum to supply the AV node (in 50-60 % of hearts), proximal parts of the bundles (branches) of His, and the parts of the posterior interventricular septum that surround the bundle branches.

Function:
The coronary arteries supply blood to the myocardium (heart tissue) itself; that is, coronary capillaries deliver oxygenated blood (nutrients) to all of the heart's cells. Numerous clinically relevant arterial branches arise from the right coronary artery, including those that supply the conduction system.

Importance in cardiovascular diseases:
Notably, the right coronary artery branches supply the sinus and atrioventricular nodes; hence, blockage in these vessels can lead to conduction abnormalities. Coronary artery disease is generally defined as the gradual narrowing of the lumen of the coronary arteries due to atherosclerosis. Atherosclerosis is a condition that involves thickening of the arterial walls via cholesterol and fat deposits that build up along the endoluminal surface of the arteries. With severe disease, these plaques may become calcified, increase in size, and eventually cause significant stenosis; a stenotic vessel has an increased vascular resistance relative to that of healthy vessels. A steady decrease in arterial cross-sectional area can eventually lead to complete blockage of the artery. As a result, oxygen and nutrient supply to the myocardium decreases below the level of demand. As the disease progresses, the myocardium downstream from the occluded artery can become ischemic.