Drug-Coated Stents Have Dark Side
Cost of Improved Artery-Opening Devices: Small Death Risk
New Stents on the Way
Tomorrow's drug-coated stents may solve the blood-clotting problem.
One strategy is to make the drug-carrying polymer dissolve when its job is
done. Another strategy is to make stents that dissolve entirely. One company
working on this problem is Biosensors International.
"With any new advance in science, there is always a 'Gotcha!' and it
appears there is a very small risk of late blood-clotting with some of the
first-generation stent designs," Biosensors Chief Technology Officer John
Shulze tells WebMD. "We believe we have a solution for that."
Biosensors has developed a drug-eluting polymer stent coating that dissolves
over time. Shulze says small clinical trials show it works. But he warns that
larger studies will be needed.
"These products are coming. And for doctors, I think they couldn't come
soon enough," Shulze says.
Another idea is to speed the process by which the body coats stents with a
new lining of blood vessel cells. Once this lining is in place, there's little
risk of blood clots.
In the Nov. 7 issue of the Journal of the American College of
Cardiology, Mayo Clinic researchers Gurpreet S. Sandhu, MD, PhD, and
colleagues report that a magnetized stent can speed this process.
From the blood, Sandhu's team isolates cells that grow into blood vessel
They then grow these cells in a Petri dish along with tiny iron particles.
As the cells grow, they incorporate these particles.
Then, during an angioplasty procedure, the researchers insert a magnetized
stent and release the iron-carrying cells upstream of the stent. The magnetized
stent holds the cells in place, where they quickly grow into a new blood-vessel
It works -- but so far, only in large animals. Human trials await the
development of safer materials.
"Human studies are several years down the road," Sandhu tells WebMD.
"We want to make sure this is 100% safe before we try this in
Bhatt asks patients to remember that every technology comes with risks as
well as benefits.
"Having said that, the current generation of drug-eluting stents is an
advance," he says.
"Next generations will be better. Each one of these technologies will
have certain limitations and liabilities," says Bhatt. "Every
intervention does carry some risk. We just need to make sure the procedure
really is indicated in the first place."