Jennifer Matthews: A quarter of people with heart disease will first feel the signs of the disease right where you'd expect.

Dr. Samuel Butman: It's a heavy feeling. It's a pressure feeling. It's like an elephant sitting on your chest.

Jennifer Matthews: That heavy feeling is angina or chest pain. Treatment is usually medication, angioplasty or a heart surgery. Now, injecting a dose of DNA directly to the heart may help the sickest of patients.

Dr. Samuel Butman: The idea is simple and that is to get blood vessels to form in the heart.

Jennifer Matthews: A new drug filled with DNA, triggers new vessels to grow inside the heart. Injected directly into the arteries, the drug restarts the heart's natural response.

Dr. Samuel Butman: What we're doing here is actually injecting a higher dose of that same kind of protein to do what the body normally does, except more of it.

Jennifer Matthews: Maurice Lattari battled heart disease for 26 years. Chest pain was part of life.

Maurice Lattari: It's very debilitating. I've been active all my life and this just takes and cuts me off at the knees.

Jennifer Matthews: Maurice took part in the study and although he is not sure if he got the gene or the placebo, Maurice says he's never felt better.

Maurice Lattari: It's turned my life around 180 degrees. I'm at the top of the world right now. I can't ask for it any better.

Jennifer Matthews: With his wife Deanna, by his side, Maurice can now enjoy life's simple treasures in comfort. This is Jennifer Matthews reporting.