DALLAS, Texas, June 30--Implanting a stainless steel coil--called a stent--to keep blocked arteries open is more effective for people who have had heart attacks than simply expanding the vessels with conventional balloon angioplasty, a Dutch study shows.
People with the stents in their blood vessels have a lower incidence of subsequent heart attacks and require fewer treatments to restore blood flow to the heart, according to a paper published in today's Circulation: Journal of the American Heart Association.
Stents have been primarily used in patients with coronary heart disease who have not had heart attacks. The question answered by the study at the Hospital De Weezenlanden, in Zwolle, the Netherlands, was whether stents would be useful in heart attack survivors as well, according to Gregg W. Stone, M.D., of the Cardiovascular Institute of Mountain View, Calif., who wrote an editorial accompanying the article.
The study showed that stenting was useful, with some qualifications.
In balloon angioplasty, cardiologists insert a balloon into the blood vessel where blood flow is obstructed by atherosclerosis. When inflated, the balloon expands the inside walls of the vessel, compressing cholesterol-laden plaque blocking the vessel. When the balloon is removed, however, the vessels can recoil, leaving the opening narrower than it was with the inflated balloon, a condition known as restenosis.
In stenting, cardiologists insert a coil--usually a cage of surgical-grade stainless steel somewhat resembling chicken wire--into the artery. The stent, which becomes permanently incorporated in the wall of the vessel, is strong and rigid, and holds the vessel open from the inside out, preventing recoiling.
The Dutch scientists, led by Harry Suryapranata, M.D., Ph.D., studied 227 patients with heart attacks at the department of cardiology in the Zwolle hospital. Of those, 112 were randomly selected to receive stents and 115 were treated with conventional balloon angioplasty.
Only one stented patient had another heart attack compared to eight angioplasty patients. Four stented patients needed subsequent treatment of their blocked arteries, while 19 angioplasty patients required a further treatment.
According to Suryapranata, the study should be viewed as preliminary. Additionally, the patients studied may have been more suited for stenting rather than angioplasty.
"The results may not be generalizable to all patients with acute heart attacks," he wrote.
"It's a relatively small study from a single center," Stone said, "and the outcomes were so incredibly excellent--a little better than we would have expected. Larger experiences from multiple centers suggest it is not quite as good as they found in their study."
For copies of the study, please telephone: 214-706-1173
Co-authors are: Arnoud W.J. van't Hof, M.D.; Jan C.A. Hoorntje, M.D., Ph.D.; Menko-Jan de Boer, M.D., Ph.D., and Felix Zijlstra, M.D., Ph.D.
NR 98-4916 (Circ/Stone)
Media advisory: Dr. Suryapranata can be reached by phone at 31 38 424 4229 or by fax at 31 38 424 3083. Dr. Stone can be reached by phone at 650-969-8600 or by fax at 650-969-2807. (Please do not publish numbers.)