NEW ORLEANS (AP) - Tiny clogged arteries in the heart that have long bedeviled cardiologists' attempts at repair can now be kept flowing smoothly with new drug-coated stents that have already revolutionized treatment of larger vessels.
Research released Sunday suggests these tiny wire coils should solve one of the major problems of treating people with chest pain caused by buildups in the arteries that feed their hearts.
While fat arteries are relatively easy to fix, about two-thirds of patients undergoing angioplasty suffer from blockages in very skinny ones - under two millimeters in diameter. Typically doctors squeeze these arteries open with a balloon and install a stent, but about half the time, they clog shut again.
Over the past year, many doctors have switched to a new kind of stent - Johnson & Johnson's Cypher - that exudes a drug that prevents the artery from filling in. Results from early studies suggested they may work for small arteries as well as big, but a team from Italy was the first to test the idea directly.
Their data, released in New Orleans at a meeting of the American College of Cardiology, showed a dramatic improvement with the Cypher stent in small arteries, reducing the failure to just 10 percent.
"This is very important, because these are the vessels that give us the most problems," commented Dr. George Mensah, cardiology chief at the Centers for Disease Control and Prevention.
The meeting, one of they world's premier showcases for heart treatment advances, included a variety of other reports on advances in cleaning up clogged arteries.
One study suggested that doctors installing the coated stents may be able to eliminate balloon angioplasties entirely. Instead, they simply pull in the coiled up stent and pop it open, pushing aside the blockage.
Another showed promising results on the use of Guidant Corp.'s system for cleaning up the carotid arteries in the neck. The approach involves placing a stent and temporarily inserting a filter intended to trap stirred-up gunk before it floats to the brain, causing strokes. Doctors say it could be an alternative to endarterectomy, the standard surgery.
In the Italian study, sponsored by Johnson & Johnson, Dr. Diego Ardissino and others from the University of Parma tested the stents in 257 patients. They were randomly given Cypher stents or the standard bare metal kind.
Cleaning up "small coronary arteries is not a small problem," said Ardissino. In fact, the smaller the vessel, the more likely it is to clog up again.
After eight months of follow-up, 10 percent of the arteries in those getting the Cypher stent had closed up again, compared with 53 percent in patients receiving the older style plain stents.
Other complications were also reduced. Two patients getting the drug-coated stents suffered later heart attacks, compared with eight getting the ordinary kind.
"Finally today we've really got a means to effectively revascularize small coronary arteries," said Ardissino.
The success of these new stents has emboldened many doctors to forgo balloon angioplasty, which may contribute to later failure of the procedure by damaging the artery wall. Dr. Jeffrey Moses of Lenox Hill Hospital in New York City said about 40 percent of stent procedures now skip angioplasty.
To test the safety of this approach, Moses and colleagues compared "direct stenting," as it is called, to the classic approach in 225 patients. The study, financed by Johnson & Johnson, found results actually appeared better.
Just 3 percent closed up again. That compares with 9 percent in those who got angioplasty first in earlier studies.
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EDITOR'S NOTE: Medical Editor Daniel Q. Haney is a special correspondent for The Associated Press.
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On the Net:
Conference: http://www.acc.org/2004ann-meeting/home/home.htm
