Heart bypass surgery performed on a beating heart is just as safe and effective as when the procedure is performed on a still heart, a new study shows.

The first long-term study to compare the two methods of heart bypass surgery shows that both methods are equally effective in restoring blood flow to the heart. Both methods are also equally effective long-term treatments for keeping open the vessels that are operated on.

"Our data shows that operating on a beating heart is as safe and effective as the traditional method of placing patients on a heart-lung machine during surgery," says researcher Petr Widimsky, MD, DrSc, professor of cardiology at the University Hospital Vinohrady in Prague, Czech Republic, in a news release.

Researchers say the so-called “off-pump” bypass surgery technique has been used for more than eight years, but until now no studies had compared the newer off-pump method to the traditional method (on-pump with a heart-lung machine).

The results, which appear in the Nov. 23 issue of Circulation: Journal of the American Heart Association, indicate that neither method is superior to the other; the choice should be made on an individual basis.

Off-Pump Heart Bypass Surgery Just as Good

About 500,000 heart bypass surgeries are performed each year in the U.S. During the procedure, the surgeon creates a detour around clogged arteries using a healthy blood vessel graft taken from another part of the body, usually a chest vessel or vein in the leg.

Until recently heart bypass surgeries required use of a heart-lung machine to allow surgeons to stop the heart during the procedure while keeping blood flowing to the rest of the body. But use of a heart-lung machine can increase the risk in some patients of stroke, heart attack, and in rare cases, death.

During an off-pump heart bypass procedure, the surgeon operates on a beating heart rather than a still one, which is technically more demanding.

In the study, researchers compared how each type of procedure affected the risk of reclogging of the bypassed artery or other complications. Four hundred people with clogged arteries were randomly assigned to undergo on- or off-pump heart bypass surgery and then followed for one year.

The study showed that both methods appeared equally effective, and chest arteries reclogged in 9 percent of patients in both on- and off-pump patients.

In addition, the rate of reclogging in leg bypass grafts did not differ significantly between the two groups (41 percent in the on-pump group vs. 51 percent in the off-pump group).

Researchers say they believe the results will likely cause the use of the off-pump heart bypass surgery method to increase. It’s currently used only in about one-quarter of heart bypass surgeries.

By Jennifer Warner, reviewed by Brunilda Nazario, MD

SOURCES: Widimsky, P. Circulation: Journal of the American Heart Association; Nov. 23, 2004; vol 110. News release, American Heart Association.