Jennifer Matthews: You could call James Duke the school mailman. Each day, he delivers mail in this school district. It's not a difficult job, but it's one James has had a hard time doing.

James Duke: I just had chest pain -- just hurt like someone standing on my chest all the time.

Jennifer Matthews: Like a tree, the heart has three main branches that separate into smaller twigs or arteries. In James' heart, his smaller arteries were blocked.

James Duke: My doctor asked me if I'd like to get in this program because they said there wasn't much more they can do, so I said, 'What have I got to lose?'

Jennifer Matthews: James had a protein hormone injected directly into his heart. The goal -- to grow new arteries.

Dr. Lynne Wagoner: We think that this is the most appropriate use of the hormone to inject it and have it do its thing and be gone from the body.

Jennifer Matthews: Cardiologist Lynne Wagoner has done this treatment on eight patients. Gail Keller is one of them. Before the injection, there is no blood flow in this area of the heart. After the injection, a new group of arteries are formed.

Dr. Lynne Wagoner: They're very, very small, very tiny arteries but yet that's what delivers heart flow to the heart muscle.

Jennifer Matthews: James is the first man in the United States to have the procedure.

James Duke: It's amazing because I was really having a rough time there for awhile.

Jennifer Matthews: Since the blood is now being delivered to his heart, he can deliver mail to the schools a little easier. This is Jennifer Matthews reporting.