Medical Device Daily

Three years after he helped send sales of drug-eluting stents (DES) plummeting with a presentation challenging their long-term safety, Eduardo Camenzind, MD, was back at the European Society of Cardiology (ESC; Sophia Antipolis, France) to say in an opening plenary session that he is unrepentant.

The use of DES results in a decrease in restenosis at the price of increased late stent thrombosis, Camenzind, from University Hospital (Geneva, Switzerland) said, providing a critical review of studies published in the wake of the safety scare he set off in 2006.

DES sales peaked in 2006 at almost $6 billion worldwide.

Following the firestorm from Barcelona where Camenzind's concerns were amplified by findings from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR), European usage of DES dipped slightly, staying between 40% to 50% of percutaneous coronary interventions (PCI), while sales in the U.S. crashed from over 90% usage in early 2006 to around 55% before the end of that year, where it plateaued. (Medical Device Daily, Sept. 3, 2008)

Camenzind acknowledged that there is greater understanding today of late stent thrombosis for DES patients, and that its causes are due to the convergence of multiple factors.

He also noted that in the three years since his presentation of safety concerns, the issues have only been complicated by the number and diversity of stents introduced to European practice.

Camenzind complained the raft of papers published over the intervening three years only contribute to clinical suspicions saying that reassuring findings about DES are coming from underpowered studies and dubious data with a failure to report p-values that mask their statistical significance.

Camenzind concluded that his doubts about total death and myocardial infarction in potent DES, as compared with bare-metal stents, "cannot in my view be definitively dissipated since Barcelona 2006," according to Heartwire.

For Camenzind, guidance for use of DES in practice centers on the potency of the DES and whether the stent leaves a polymer coating permanently in the patient's artery.

The discussion then took a powerful reversal in tone with a presentation by Adnan Kastrati, MD, of Deutches Herzzentrum (Munich, Germany) who said the idea of DES being the source of stent thrombosis, which was "born in Barcelona in 2006, is already dead," according to TCTMD, a publication of the Cardiovascular Research Foundation.

"We have to bury this in exactly the city where it was born," he said.

Reviewing data from randomized trials, Kastrati said evidence coming from randomized clinical trials and meta-analyses generally confirm the efficacy and safety of DES, including for high-risk patient groups, such as those with diabetes and myocardial infarction.

He ceded the point, however, that none of the randomized trials had enough power to reliably evaluate the safety of DES, and those meta-analyses compiling these study results are not a substitute for a large specific trial on stent thrombosis with long-term follow up.

Acknowledging the rapidly evolving technology of DES, and the need to distinguished between these different types of DES, he nonetheless reached the opposite conclusion of Camenzind saying there are good reasons to believe the benefit of DES for stemming restenosis is not achieved at the expense of compromised safety.

In a press conference ahead of the plenary session, Stefan James, MD, from the Uppsala Clinical Research Center (Uppsala Sweden) said the controversy sparked in Barcelona in 2006 provided a much-needed wake-up call for PCI practitioners

"All of us interventional cardiologists were overly enthusiastic," he said to reporters, "we thought that DES would solve everything and we started to stent patients we never should have stented."

The warning about DES safety resulted in closer scrutiny, "making us think about how to improve techniques, the antiplatelet therapy, and the selection of patients to get it right," he said.

In his plenary presentation James reviewed updated data from the 2006 SCAAR registry, which was used as part of an FDA hearing and showed that during almost three years of follow-up the rates of adverse events, including death, were significantly higher among patients receiving a DES than among patients receiving a bare-metal stent (BMS).

With data now running out to five years, James reported SCAAR data shows no difference between the two patient groups for adverse events.

Yet the opening plenary session, titled "Is it time to turn the page on Barcelona 2006?" ended in a draw among the nearly 5,000 cardiologists in attendance.

The co-chairs for the session, Michal Tendera, MD, from the Silesian School of Medicine (Katowice, Poland), and Anthony Gershlick, MD, from University Hospitals (Leicester, UK) called for a vote among audience members both before and after the debate, asking whether cardiologists continue to believe DES safety is a valid clinical controversy.

The vote was split both before and after the discussion, and one panel member, David Holmes, a cardiologist at the Mayo Clinic (Rochester, Minnesota), suggested the debate was far from over.

"We need to come back to Barcelona in three years in order to discuss this important topic again," he said.