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ATLANTA, G.A. -- Up to $162 million could be saved annually
if cardiologists implant artery tubes called stents into a more
select group of patients, according to a new cost analysis
performed by Duke University Medical Center cardiologists.

The researchers said the cost savings could be achieved
without compromising the quality of patient care.

Stents are tiny metal tubes implanted in the artery
immediately after an angioplasty to help prevent the artery
from renarrowing, a process known as restenosis. In an
angioplasty procedure, a tiny balloon is inflated at the site
of an arterial blockage, cracking and displacing the plaque and
restoring blood flow to the heart.

As the popularity of stenting has grown, many cardiologists
now automatically implant a stent, even when an excellent
result is achieved with the balloon alone. Stents are used in
more than 500,000 procedures in the United States every
year.

"We have shown that there is a group of patients whose
arteries are very unlikely to renarrow after angioplasty and
who get stent-like results without needing the stent," said
cardiologist Dr. Warren Cantor, who led the analysis. "The
amount of potential health care savings range from $114 million
to $162 million."

Cantor prepared the results of his analysis for presentation
Wednesday at the annual scientific sessions of the American Heart Association.
The study was supported by the Royal College of Physicians and
Surgeons of Canada.

Previous studies by the same Duke team found that
approximately one in 12 patients may not need stents because
their vessels are very unlikely to renarrow after balloon
angioplasty. The researchers determined this after an analysis
that showed that those patients least likely to have
renarrowing of the artery had "stent-like" results (less than
30 percent residual narrowing) immediately after balloon
inflations. They also had three common characteristics: they
were men, their vessels had shorter atherosclerotic lesions,
and the location of the lesion involved was not at the top of
the left anterior descending artery (LAD), the artery that
supplies blood to the front of the heart.

In their analysis, the researchers pooled the results of
seven different angioplasty trials and an angioplasty registry
totaling 5,143 patients. They then compared what the costs
would be of pursuing each of the following three treatment
strategies:

Every patient receives a stent. All patients receive a stent
except those who have "stent-like" results after balloon
angioplasty alone. All patients receive a stent except those
with "stent-like" results who are male, have short lesions and
no lesions located in the proximal LAD artery.

"Based on the combination criteria, about 8 percent of the
patients wouldn't need a stent, at a savings of $114 million
per year," Cantor said. "If the decision to stent was based
solely on how the vessel looked immediately after angioplasty,
18 percent of patients wouldn't require stenting, at a savings
of $162 million."

The benchmark for clinical success of these procedures is
whether or not the treated vessels renarrow and the patient
needs another artery-opening procedure, whether it be
angioplasty or coronary artery bypass surgery. In this
analysis, the combination group had a 14 percent
revascularization rate six months after the procedure, similar
to that seen with stent insertion.

"We were pleased to find that relatively simple criteria
could identify patients at very low-risk for requiring repeat
revascularization after treatment with balloon angioplasty
alone," Cantor said. "Although only a small proportion of
patients are in this very low-risk group, the potential cost
savings are substantial."

Before the advent of stents, up to one-third of all patients
who received an angioplasty needed another angioplasty or a
bypass operation after six months due to restenosis. Since the
introduction of stents in the United States, less than 10 years
ago, the restenosis rate has been nearly cut in half.

While stents have markedly reduced the rate of restenosis,
Cantor said stents have their own drawbacks. When restenosis
does occur within a stent, it is more difficult to treat. Also,
there is a slight (1 percent) risk of clot formation in the
stent, which could lead to myocardial infarction.