(CNN) -- Actor and comedian John Ritter has died unexpectedly after he was rushed to the hospital for a "dissection of the aorta," his publicist Lisa Kasteler told CNN.
Ritter, who would have turned 55 next week, was the star of the ABC series "8 Simple Rules for Dating My Teenage Daughter."
In a statement, Kasteler said Ritter was rushed to the hospital after suffering from an unrecognized and undetected flaw in his aorta.
Surgeons at the hospital tried to save the Emmy Award-winning actor but were unable to do so, the statement said.
WebMD.com described an aortic dissection as "an abnormal separation of tissues within the walls of the aorta" caused by high blood pressure, family history of the condition, disease of connective tissue, or severe trauma to the chest.
"Aortic dissection results in a weakened blood vessel wall that may also rupture," the Web site says.
Ritter was best known for his role as Jack Tripper on the long-running television sitcom, "Three's Company."
He was the youngest son of Western film star and country music legend Tex Ritter, according to his biography on ABC's Web site.
John Ritter was born on September 17, 1948. He is survived by his wife, Amy Yasbeck, and their daughter, Stella, and three children -- Carly, Tyler and Jason -- from his first marriage to Nancy Morgan.
