An aneurysm or aneurism (from Ancient Greek: ἀνεύρυσμα - aneurusma "dilation", from ἀνευρύνειν - aneurunein "to dilate") is a localized, blood-filled balloon-like bulge in the wall of a blood vessel. Aneurysms can commonly occur in arteries at the base of the brain (the circle of Willis) and an aortic aneurysm occurs in the main artery carrying blood from the left ventricle of the heart. When the size of an aneurysm increases, there is a significant risk of rupture, resulting in severe hemorrhage, other complications or death. Aneurysms can be hereditary or caused by disease, both of which cause the wall of the blood vessel to weaken.

Aneurysms may be classified by type, location, and the affected vessel. Other factors may also influence the pathology and diagnosis of aneurysms.

A true aneurysm is one that involves all three layers of the wall of an artery (intima, media and adventitia). True aneurysms include atherosclerotic, syphilitic, and congenital aneurysms, as well as ventricular aneurysms that follow transmural myocardial infarctions (aneurysms that involve all layers of the attenuated wall of the heart are also considered true aneurysms).

Kurt Donald Cobain (February 20, 1967 – April 5, 1994) was an American singer-songwriter, musician and artist, best known as the lead singer and guitarist of the grunge band Nirvana. Cobain formed Nirvana with Krist Novoselic in Aberdeen, Washington in 1985 and established it as part of the Seattle music scene, having its debut album Bleach released on the independent record label Sub Pop in 1989.

After signing with major label DGC Records, the band found breakthrough success with "Smells Like Teen Spirit" from its second album Nevermind (1991). Following the success of Nevermind, Nirvana was labeled "the flagship band" of Generation X, and Cobain hailed as "the spokesman of a generation". Cobain, however, was often uncomfortable and frustrated, believing his message and artistic vision to have been misinterpreted by the public, with his personal issues often subject to media attention. He challenged Nirvana's audience with its final studio album In Utero (1993).

During the last years of his life, Cobain struggled with heroin addiction, illness and depression. He also had difficulty coping with his fame and public image, and the professional and lifelong personal pressures surrounding himself and his wife, musician Courtney Love. On April 8, 1994, Cobain was found dead at his home in Seattle, the victim of what was officially ruled a suicide by a self-inflicted shotgun wound to the head. The circumstances of his death at age 27 have become a topic of public fascination and debate. Since their debut, Nirvana, with Cobain as a songwriter, has sold over 25 million albums in the U.S. alone, and over 50 million worldwide.