Diabetics who have a heart attack are
much more likely to survive if they have previously had bypass surgery than if
they have had another procedure called balloon angioplasty, according to a new
report.
When a vessel that delivers blood to the heart becomes blocked, options for
restoring blood flow to the heart include bypass surgery and a procedure called
balloon angioplasty. Bypass surgery involves taking veins, and sometimes
arteries, from other parts of the body and grafting them from the aorta to the
coronary artery to bypass the blocked vessel. During angioplasty a
balloon-tipped catheter is threaded into a blocked artery and inflated,
flattening fatty plaques against the artery wall.
Recently published study findings had already shown that people with
diabetes survive longer after having bypass surgery than after angioplasty. But
why this should be the case was not clear. To find out why, a team of
researchers led by Dr. Katherine M. Detre, of the University of Pittsburgh,
Pennsylvania, reanalyzed the data.
In the study, 8% of people with diabetes and 4% of those without the disease
had a heart attack. In people who did not have diabetes who had a heart attack,
the effects of angioplasty and bypass surgery were roughly the same.
But bypass surgery provided "dramatic" protection to diabetics who had a
heart attack. Specifically, just 17% of diabetics who had bypass surgery died
after a heart attack, compared with 80% of those who had angioplasty.
"Treated diabetic patients who had coronary bypass surgery are more likely
to survive a heart attack than diabetics who had angioplasty," Detre told
Reuters Health in an interview. She said that bypass surgery "provides a
protective effect for patients who experience heart attack."
Detre pointed out that diabetics who had bypass surgery and then had a heart
attack were about as likely to survive the heart attacks as people without
diabetes. "It was as if they didn't have diabetes," she said.
In an editorial that accompanies the study, Dr. Steven M. Haffner, of the
University of Texas Health Science Center in San Antonio, writes that patients
with diabetes who undergo angioplasty should also be treated aggressively for
heart risk factors and for their diabetes. He notes that several types of
medications, including aspirin, beta-blockers and ACE inhibitors have been shown
to help prevent heart attacks.
