[Miles O'brien, Cnn Anchor:] Now, nearly half of all heart bypass patients suffer a drop in brainpower help me this, will you, Rhonda that's a measurable five years after surgery. That study is reported in this week's "New England Journal of Medicine." But now some heart surgeons believe they have a safer way to perform the surgery: It's called beating heart surgery and medical correspondent Rhonda Rowland is here to tell us what that means. And it's literally beating heart surgery, right?
[Rhonda Rowland, Cnn Medical Correspondent:] That's right and we're going to have a story to show you this. And doctors hope this new beating heart surgery, which avoids the use of the heart-lung machine, will help prevent some of this mental decline. And according to this new study, the amount of brain power that's lost during a bypass operation is about the same as the brain power we now lose between the ages of 40 and 60.
[Rowland:] Dean Maloney is having a heart-bypass operation that's being performed in a new way: to protect his brain.
[Unidentified Male:] So this man's going to have two grafts done, one with each of his mammary arteries.
[Rowland:] Doctors are calling it beating heart surgery.
[Unidentified Male:] This device has suction cups on it, which suck onto the surface of the heart and hold it still.
[Rowland:] Using a vacuum-like device, surgeons hold still just the part of the heart they're working on while the rest of the heart continues beating.
[Unidentified Male:] Specifically, we hold still the coronary artery that we're sewing the graft to, and then work with that artery, finish that job there, and then move to the next part of the heart that needs another graft.
[Rowland:] In traditional heart bypass, the patient's heart is stopped while the surgeon sews on the new arteries. The patient is kept alive with a heart-lung machine. But there are potential risks.
[Unidentified Male:] The heart-lung machine causes some inflammation that affects the brain and the lungs and the kidneys and the heart and every organ in the body. Most patients tolerate that inflammation very, very well and do fine.
[Rowland:] But some don't. Dr. Denise Barbut studies the brain damage often caused by bypass surgery, the most troubling risk
[Dr. Denise Barbut, Neurologist:] Neurocognitive dysfunction occurs in up to 60, 70 percent of patients, of all patients undergoing coronary bypass surgery. It is still present two months after the operation in 25 to 30 percent of them, and is that is permanent.
[Rowland:] In most patients, the damage is subtle: personality, mood changes, depression. But a small percentage of patients suffer a stroke. [on camera]: If you're going to have a heart-bypass operation, chances are your surgeon will not be using the new beating heart surgery. Worldwide, just 15 percent of all doctors have learned the procedure. The reason: There still is no definitive proof the new way is better. [voice-over]: A comparison of the stopped heart approach and the beating heart surgery should be completed in about a year. In the meantime, Dr. Puskus says his experience with 400 patients has been encouraging.
[Unidentified Male:] We have a mortality rate of less than one percent and a stroke rate that seems to be just slightly less than it would normally be.
[Rowland:] Patients are also leaving the hospital 1 12 days earlier, which saves money. For Dean Maloney, the beating heart surgery was a success.
[Unidentified Male:] I didn't feel any different mentally. It was physically, I just hurt. Of course, they only sawed my chest open why would I hurt?
[Rowland:] It took two months after the operation before his body was ready to endure the rigors of the road, but his mind, he says, was rolling from the start.
[O'brien:] All right, keep us posted, will you, Rhonda?
[Rowland:] Certainly.
[O'brien:] CNN's Rhonda Rowland, checking in with us.