The condition is known as Aneurysm.
An aneurysm refers to a weakening of an artery wall that creates a bulge, or distention, of the artery. Most aneurysms do not show symptoms and are not dangerous. The bulge can rapture and cause internal bleeding.The exact cause is unclear but certain factors contribute toe the condition,for example; damaged tissue in the arteries can play a role, arteries can also be harmed by blockages such as fatty deposits.