Treating blocked coronary arteries using stents is superior to traditional balloon angioplasty, according to a new study.
The Optimal PTCA versus Primary Stent Strategy (OPUS) Trial was designed to determine whether coronary stents should be routinely implanted as the first form of treatment or only when necessary following imperfect balloon angioplasty outcomes.
Results of the trial were presented at the American College of Cardiology scientific sessions in New Orleans by W. Douglas Weaver, M.D., co-director of the Henry Ford Heart and Vascular Institute in Detroit who headed the study.
A stent is a small, slotted, stainless steel tube that is expanded and permanently left in place to keep the blocked coronary artery open.
PTCA, or balloon angioplasty, involves inserting a balloon through a catheter and inflating it to compress arterial plaque and enlarge the blood vessel so blood can flow more easily. The balloon is then deflated and the catheters are withdrawn.
Forty-four participating centers in the U.S. and Canada randomly allocated patients for either stent implantation or initial balloon angioplasty followed by stents only when necessary. At six months the rate of death, heart attack and the need for a second procedure was: 6.1 percent for the primary stent group; and 14.9 percent for the balloon angioplasty/provisional stent group.
The six-month cost difference was also significant. In most cases primary stenting cost less. The initial stent procedure cost was $1,000 higher because of the price of the stent itself. But after six months the cost was actually $200 lower because the balloon angioplasty required further hospitalizations and treatment.
"The number of hospitalizations was almost two and a half times higher for the balloon angioplasty/provisional stent group," Dr. Weaver said.
According to Dr. Weaver, stents have revolutionized the way in which cardiologists treat blocked coronary arteries. Today, an estimated 75-80 percent of patients with coronary artery blockage are treated using stents. Most earlier studies have shown that if an optimal result is achieved by balloons, stents are probably not necessary.
Dr. Weaver acknowledges that despite their benefits, stents can have their own set of problems. Stent restenosis, or recurring narrowing of the coronary artery, is difficult to treat when it occurs. The devices cost considerably more than balloons.
"We were surprised that routine stenting was better because the initial balloon results were very good. But primary stenting was more effective after six months," Dr. Weaver said. "While some cardiologists have suggested that stents are overutilized, these results support that practice and the superiority of these devices."
Dr. Weaver continued, "At the time of the study, most patients received the Johnson & Johnson Palmaz-Shatz" stent -- the first one approved in the United States. Today's improved stent designs are likely to further magnify the difference observed here."