National Letter of Intent. The National Letter of Intent (NLI) is a document used to indicate a student athlete's commitment to participating National Collegiate Athletic Association (NCAA) colleges and universities in the United States.
Collateral Vessel Closure. Collateral vessels are abnormal blood vessels that connect the aorta with the pulmonary arteries. The aorta is a blood vessel that carries blood from the heart to arteries throughout the body.Pulmonary arteries are the vessels that transfer blood from the heart back to the lungs for oxygen.Everyone has collateral vessels, but they're normally small and not in use.They become enlarged in some people with congenital heart disease (heart disease that's present since birth).ulmonary arteries are the vessels that transfer blood from the heart back to the lungs for oxygen. Everyone has collateral vessels, but they're normally small and not in use. They become enlarged in some people with congenital heart disease (heart disease that's present since birth).
A American Heart Association-Stroke Association answered. Collateral circulation is the process in which a system of small, normally closed arteries connect and start to carry blood to part of the heart when a coronary artery is blocked, or to part of the brain when a cerebral artery is blocked.These arteries can serve as alternate routes of blood supply. American Heart Association-Stroke Association answered. Collateral circulation is the process in which a system of small, normally closed arteries connect and start to carry blood to part of the heart when a coronary artery is blocked, or to part of the brain when a cerebral artery is blocked.