Bypass surgery safer with heart-lung pump: study
Last Updated: Thursday, November 5, 2009 | 4:42 PM ET
CBC News
Doing bypass surgery while the heart is still beating was thought to result in fewer complications, but a new U.S. study suggests going on a heart-lung machine is actually the safer approach.
Traditionally, heart bypass patients are hooked up to a heart-lung machine that circulates blood while the beating heart is stopped. In the 1990s, surgeons began doing "off-pump" surgery — using devices that stabilize the beating heart instead of a heart-lung machine.
The one-year risk of heart attack, death or further heart surgery increased if surgeons worked on a heart that remained beating, researchers reported in Thursday's New England Journal of Medicine.
"For the vast majority, there's no advantage to doing it off-pump and there may be some disadvantages," said Dr. Frederick Grover of the University of Colorado Denver, one of the leaders of the study.
The study looked at 2,203 patients at 18 Veterans Affairs medical centres in the U.S. Half were randomly assigned to bypass surgery with a heart-lung machine and half without.
A year after surgery, heart-related deaths occurred in 2.7 per cent of the off-pump patients, compared with 1.3 per cent among the other group.
Fewer off-pump participants had bypassed arteries that remained open after a year — about 83 per cent compared with 88 per cent among those who were hooked up to a heart-lung machine.
Because the heart is full of blood during off-pump surgery, it's harder to reach and repair the arteries at the back of the heart, Grover explained.
Off-pump surgery "will probably remain a technique reserved for selected patients and skilled surgeon advocates," Dr. Eric David Peterson of Duke University Medical Center wrote in a journal commentary.
The study shows how less-invasive methods are always better, said Peterson, who called the study "remarkably well done."
Previous studies have suggested that women and the elderly may do better without the pump, while the study was mostly on younger, healthier men, he noted.
About 20 per cent of bypasses in the U.S. are done without a pump.
With files from The Associated Press
