ROANOKE, Va. - Heart disease is the leading cause of death in America; hundreds of people walked in Roanoke on Saturday morning in an attempt to change that. More than 2,000 people participated in Roanoke's Heartwalk, which traveled up the Roanoke River Greenway from River's Edge Park. The event raised more than $350,000 for the American Heart Association. "I had a widowmaker and I wasn't going to make it," said Clyde Childs, who suffered a heart attack two years ago. The Heartwalk also raised money in honor of Dr. Gray Swank, a Carilion Clinic cardiologist who was murdered earlier this year while on a fishing trip in Belize.