Medical Device Daily
ATLANTA — While the jury is still out on drug-eluting stents being safer and more effective than bare metal stents (Medical Device Daily, March 16, 2010), there is one question about the popular devices that can be conclusively answered. That is that the latest generation of DES seem to be much safer than their predecessors, according to a panel at the 59th Annual Scientific Session of the American College of Cardiology (ACC; Washington).
As many crowded their way into the early morning session, which provided an update on DES, as well as key long-term data on several clinical studies regarding the devices, it seemed as if this particular part of the device's efficacy debate was at long last put to rest.
“The benefits of drug-eluting stents significantly outweigh a possibly small increased risk for stent thrombosis,“ Debabrata Mukherjee, MD, a cardiologist with the University of Michigan Health Center (Ann Arbor). “As compared with bare metal stents, drug eluting stents are associated with a similar long-term incidence of death or myocardial infarction but provide a clinically important decrease in the rate of restenosis among high-risk patients.“
But on top of the benefits, issues still tend to remain regarding the popular treatment option.
Mukherjee specifically spoke on the mechanisms of DES failures, and with a plethora of slides and talking points, he guided the audience through some of the key reasons for potential failures in DES.
“Restenosis following a DES implantation is an infrequent phenomenon but given widespread use of DES affects a significant amount of patients, “Mukherjee said. “Stent thrombosis may be seen up to three years after implantation, a complication rarely or not seen with BMS.“
He added that as compared with BMS, DES are associated with a similar long-term incidence of death or myocardial infarction but provide a clinically important decrease in the rate of restenosis among high-risk patients.
But the failures, he said, don't outweigh the benefit of these devices and measures have been taken to help ensure that there is a safer experience for patients who undergo DES implantation.
Perhaps one of the biggest advancements comes from thinner struts that are now used in the devices.
Panelists pointed to applications such as Boston Scientific's (Natick, Massachusetts) Taxus Liberté paclitaxel-eluting coronary stent, which incorporates the thin-strut feature. The company recently took part in the DAPT Clinical Study an independently managed large scale evaluation of DES (Medical Device Daily, Jan. 5, 2010).
“Thinner cobalt strut stents allow for easier delivery and have safer outcomes,“ said panel member David Moliterno MD, University of Kentucky (Lexington) College of Medicine division of cardiology chief. “I do think the thin struts are a step forward.“
Moliterno also said that the amount of stenting procedures have increased and that the price of DES have also dropped tremendously, since inception.
“I think one of the most significant advances from the old to new generation of DES is that the devices were roughly $3,600 now they're under $2,000,“ Moliterno told the audience. “Also we're seeing a number of the [DES stenting procedures] increase.“
But perhaps the next biggest push in the world of DES is the new polymer-free DES which is being touted as being even more effective than models on the market now.
“The durablilty of antirestenoic efficacy seen with both the Endeavor and the polymer-free dual-drug-eluting stent is encouraging and lends some support to the hypothesis that modifications in second- and next-generation drug-eluting stent systems have the capacity to impact late patient outcomes,“ said Robert Byrne, of the German Heart Center (Munich).
The spread of these new stents could perhaps even further boost the DES market, which is slightly increasing since it stumbled a few years ago.
During a Tuesday afternoon meeting with reporters, David Holmes Jr., MD, a moderator for the press conference said that he only saw the market for DES on the uptake and that new and safer drugs would only continue to push the device in popularity.
“The concern with DES is stent thrombosis, but with new agents that are available that cuts the occurrence by half,“ Holmes said. “I think [the market] will only continue to increase.“
Omar Ford; 404-262-5546