BCAA consists of the amino acids leucine, isoleucine and valine. The reason these three amino acids are called BCAA is because they branch off from the other five essential amino acids, (there are a total of eight), to create their own chain. Amino acids are responsible for the formation of proteins in the body.
An aneurysm is an abnormal bulging out or ballooning of a portion of the artery, usually due to weakness of the arterial wall. The aneurysm may enlarge and rupture, often with disastrous consequences.
Stenosis. Narrowing of a valve or an artery is called stenosis. A stenotic valve does not open completely and therefore it obstructs or blocks blood from moving through it normally. An artery can become stenotic as well, such that there is obstruction of blood flow through it to the organs of the body.