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New Heart Stents Better Than Old Ones, Study Says

A heart stent is a mesh¹ tube made of metal that, when inserted into an artery², keeps it open. 

Stents can be metal only or they can contain medicine released once the stent is in place.

These are called drug-eluting stents. And the medication they release helps the artery remain open so blood can easily flow through it.

But studies show that even with drug-eluting stents, some patients still have heart attacks. And earlier studies concluded that drug-eluting stents could actually increase the risk.

Dr. Stephan Windecker heads the interventional³ cardiology program at Bern University Hospital in Switzerland. He organized a study on a new generation of drug-eluting stents and compared them to the plain metal variety.

“There were concerns that, actually, these drug-eluting stents may lead to adverse⁴ events such as occlusion [closing] of the artery with blood clots," said Windecker.

Dr. Windecker and other researchers studied more than 1,000 heart patients who were having an emergency heart procedure. About half received a bare-metal stent while the rest received the latest medicated stent. The medicine was on a biodegradable substance. 

“That is a polymer which degrades into water and carbon dioxide during a period of six to nine months after the drug has been released and renders the stent surface more closely to a bare-metal stent," he said.

A year later, the researchers found those who got the drug-eluting stent had fewer heart problems than those who received the bare-metal variety. 

“The occurrence of new heart attacks within that treated segment was slower with the biodegradable polymer as compared to the bare-metal stent, and it reduces the incidences of serious cardiovascular events by more than 50 percent," said Windecker.

Dr. Windecker says these newest drug-eluting stents made with polymers that dissolve are better than other medicated stents made with polymers that don't dissolve.

Ideally, a layer of cells that lines the artery will grow over the stent, making it, in a sense, part of the body. 

The study was published in the Journal of the American Medical Association.