John Ritter died on September 11, 2003, at the age of 54 from an aortic dissection. This condition involves a tear in the inner layer of the aorta, the body's main artery, causing blood to flow between the layers of the artery wall and leading to potentially fatal complications. On the day of his death, Ritter was rehearsing for his TV show when he suddenly experienced chest pain, sweating, and vomiting. He was initially misdiagnosed with a heart attack and treated as such, but his condition worsened, and the correct diagnosis of aortic dissection was made too late for successful surgery. He was pronounced dead at 10:48 p.m. after being taken to a hospital in Burbank, California.
