DES Studies Shift from Efficacy to Safety Endpoints

By TCT Daily Staff

Drug-eluting stents may be associated with a more significant mortality benefit and better efficacy than previously believed, according to an overview of data from randomized trials and observational studies presented by Ajay J. Kirtane, MD, SM, from Columbia University Medical Center and the Cardiovascular Research Foundation in New York.

Kirtane said one of the important benefits of DES are their association with marked reductions in clinical restenosis endpoints. "This has been demonstrated in both on- and off-label analyses," he said.

Kirtane added that a closer review of clinical trials of DES may be necessary.

"The majority of pivotal DES vs. bare-metal stent studies have been designed or powered to show efficacy rather than other endpoints," he said.

 "DES were designed to combat restenosis, previously considered a nuisance entity.

But in studies that were designed around restenosis endpoints, DES were proven highly effective."

Safety

Kirtane noted that some critics have voiced concerns about late stent thrombosis with DES, even though this is a low frequency event.

"With concerns over late stent thrombosis, the alarm was raised and focus shifted away from efficacy towards clinical outcomes," he said.

Kirtane said research has shown favorable mortality benefits for patients treated with DES, and DES leads to fewer repeat procedures/CABG and clinical sequelae of restenosis.

Kirtane cited a recent meta-analysis by Stettler et al that showed the cumulative incidence of cardiac death was similar in patients treated with DES and bare-metal stents (see Figure 1).

Risk profile

Stephan Windecker, MD, from the University Hospital of Bern in Switzerland, discussed the safety associated with antiplatelet therapy and DES. He said some patients may be better candidates for this treatment than others.

Windecker advised physicians who are treating patients with DES that adequate inhibition of platelet aggregation during and after PCI is important. He recommended strict compliance with dual antiplatelet therapy, particularly during the first six months after stent implantation.

Windecker said more research is needed to better understand the risk of very late stent thrombosis.

"Whether dual antiplatelet therapy beyond 12 months prevents very late stent thrombosis, is associated with a lower rate of ischemic cardiovascular events, and has a favorable net clinical benefit requires confirmation in randomized, prospective trials," he said.

Windecker said each patient’s risk profile should determine the decision to prolong dual antiplatelet therapy beyond six to 12 months.

When determining a patient’s risk profile, doctors should take into account the presence of diabetes, multivessel disease, and/or previous MI.

Patients with diabetes may be at an increased risk for stent thrombosis with both DES and bare-metal stents (see Figure 2).

Windecker concluded by saying some patients may not be best-suited for treatment with either DES or bare-metal stents.

This includes patients who have an increased risk of bleeding, who have scheduled elective surgery, who require oral anticoagulation, and those who may be noncompliant with dual antiplatelet therapy because of factors such as cost, education, or psychiatric disorders.

Disclosures:

（source：www.tctmd.com）