Heart bypass surgery performed while the heart is still beating was as effective as surgery performed while a heart-lung machine did the work of the temporarily stopped heart, researchers said Tuesday.
The latest study comparing the two bypass techniques in nearly 200 patients concluded that arterial grafts carried blood equally well in examinations one month and one year after either method of surgery, said study author John Puskas of Emory University School of Medicine in Atlanta.
All the 197 bypass surgeries looked at in the study were by the same experienced surgeon, with patients chosen at random to undergo surgery with one technique or the other.
Previous research comparing the methods has shown off-pump bypass patients -- where the heart is kept beating during surgery -- lose less blood, have less risk of stroke, have less damage to their heart muscle and have shorter hospital stays than traditional bypass patients whose hearts are stopped and a heart-lung machine used to keep them alive.
An unsubstantiated benefit of off-pump surgery is that it may avoid the post-surgical mental impairment suffered by some bypass patients whose blood was pumped and cooled by a machine. The impairment can persist for years.
Roughly one in four U.S. heart bypass operations are performed off-pump, a decade-old technique that a minority of heart surgeons have mastered. There are roughly 500,000 heart bypass operations performed in the United States each year, though increased use of drugs and wire mesh stents to prop open clogged arteries may be decreasing the need for the surgery.
The study concluded that the off-pump method was slightly less expensive than traditional bypass surgery using a heart-lung machine because patients were released from the hospital around a day earlier. The mean cost of off-pump surgeries after a year of treatment was nearly $23,000 while traditional bypass surgery cost nearly $25,000.
The study published in the Journal of the American Medical Association was funded in part by Medtronic Inc., a manufacturer of equipment used to hold the beating heart in place during off-pump surgery.
An editorial commenting on the study in the same journal by Daniel Mark of Duke University in Durham, North Carolina, suggested a broader study was needed to compare the efficacy of the two bypass techniques among different classes of patients, different surgeons and multiple hospitals.