Coronary Arteries

About the Coronary Arteries

The coronary arteries supply the heart muscle myocardium with oxygenated blood, delivering approximately 250 mL per minute 5 percent of cardiac output. The left main coronary artery divides into the left anterior descending LAD supplying the anterior left ventricle, septum, and bundle branches, and the left circumflex LCX supplying the lateral and posterior left ventricle. The right coronary artery RCA supplies the right ventricle, inferior left ventricle, and in most people both the SA node and the AV node. Coronary dominance is determined by which artery gives the posterior descending artery PDA: right dominance is by far the most common pattern, with left dominant and codominant circulations occurring in a minority of people. Coronary artery disease from atherosclerosis causes angina and myocardial infarction. Occlusion of the proximal LAD, nicknamed the widowmaker, is particularly dangerous because of the large territory it supplies. Coronary angiography visualizes stenosis, treated with angioplasty and stenting or bypass surgery. Collateral circulation develops with chronic ischemia.