Medical Device Daily

PARIS – Since their introduction, drug-eluting stent (DES) devices have taken the cardiovascular world by storm. But it's not a perfect storm, according to a kick-off presentation at this year's edition of EuroPCR.

DES devices have been proven over and over as being more effective than their bare-metal antecedents, but Jean Marco, MD, of the interventional cardiology unit at Clinique Pasteur (Toulouse, France) and William Winjs, MD, co-director of the Cardiovascular Center at OLV Ziekenhuis (Aalst, Belgium) in an early morning press conference Tuesday laid out an important argument: that simply reducing the occurrence of restenosis – and thereby reducing the number of redo procedures necessary – is not the ultimate or the most important endpoint for these devices. Rather, they focused on the need for the development of DES technology that has a much more important clinical effect – the ability to stave off death.

As the main presenter in raising this issue, Marco opened the door to a variety of interesting perspectives on the future of this type of device in terms of both future orientations for this technology and, for the physician, current clinical practice.

Marco said that while the technology is just five years old, and has shown itself to be cost-effective in its ability to reduce the number of follow-on procedures, he suggested that it needs to go beyond this level of efficacy. He noted that cardiologists are already on the lookout “to resolve certain of the problems that are inherent in these devices,“ primarily thrombosis and the possibility of late, or “precocious” thrombosis – issues that others have raised in terms of unknown effects.

But more broadly he charged that there has been no evidence “of reductions in the rate of death or myocardial infarction” with the use of DES devices and that “the cumulative incidence of death and death or myocardial infarction (MI) is similar between the groups of patients treated with DES or bare metal stents.”

In a question and answer period, however, Marco was less definitive in his assertions.

He said rather that the superiority of DES devices to reduce the rate of MI or to prolong the patient's life without heart attack or death beyond that provided by use of a bare metal stent simply had not been proven. And he and Winjs agreed that to demonstrate any comparison on this issue would require trials with extremely high power – up to at least 50,000 patients – to provide real answers on the question.

Winjs told Medical Device Daily that such trials are not now in progress but are “planned.”

While noting the yet-to-be-answered questions for this technology, Marco offered a much broader view in terms of clinical practice.

He specifically advised that cardiologists take a “precautionary attitude” – an attitude that he said would “incite us to not do anything that could compromise our mission: to increase longevity while improving the quality of the life of our patients.”

A complementary expansion of his remarks appear in the EuroPCR publication, EuroIntervention, issued at the conference, in which Marco writes that the precautionary attitude “is a call to anticipate – and thus strive to understand and integrate the knowledge of risk – no matter how uncertain – into our daily practice.”

In addition, he recommends that cardiologists share the information concerning possible risks with patients as a matter of transparency, saying that transparency “is indispensable: the patient should have the freedom to choose whether or not they want to receive a DES or BMS [bare metal stent].”

While Marco's presentation issues a broad challenge to DES manufacturers, it is unlikely to rain on their parade – at least not in the short term.

But the longer-term view could mean broad challenges for the first generations of these devices, according to Winjs.

Winjs suggested that some of the issues raised by Marco will be confronted by new generations of stent device, stents with bioabsorbable polymers to attach the drug or by the stents being developed that will be entirely bioabsorbed and thus disappear altogether from the body.

Marco also pointed to another key question concerning the use of anti-platelet aggregation therapy after the implantation of a stent.

He said, “While clinical trials have demonstrated the interest in dual antiplatelet therapy during two to six months, with life-long aspirin use, in daily practice the effort for optimizing adherence to treatment are often followed by mediocre results. The decision to stop antiplatelet therapy, for whatever reason, must take these possible consequences and risks into account.”

He noted that the majority of the patients requiring this type of regimen are more than 60 years old.

“What this means is that a certain number among them will need, within two years following implantation of DES, to have an operation or suffer a bleeding event which could pose the problematic of ending antiplatelet therapy.”

Marco concluded that the attitude of precaution on these issues “should be considered as a positive step forward, stimulating new research oriented towards the controlled elution of antiproliferative drugs or new agents from improved polymer biocompatibililty and non-polymeric drug carriers or reservoirs.”