EXPERT CTO: EES safe, effective for CTO in long term

Long-term data from the EXPERT CTO clinical study indicate that annualized rates of target lesion revascularization, target vessel MI and stent thrombosis are favorable in patients with chronic total occlusions who were treated with an everolimus-eluting stent, according to a speaker at the Chronic Total Occlusion Summit.

The prospective, multicenter, single-arm EXPERT CTO clinical study included 250 patients with CTOs who were treated with an EES (Xience Prime and Xience V, Abbott Vascular), David E. Kandzari, MD, of the Piedmont Heart Institute in Atlanta, said during a presentation.

Previously published data showed the study met its primary endpoint of 1-year occurrence of MACE, defined as a composite of death, MI and TVR, compared with a historical performance goal established from six CTO trials of drug-eluting stents.

David E. Kandzari

According to the results, 1-year MACE rates were 18.5% in the intention-to-treat population (n = 222; P = .025) and 8.2% in the per-protocol population (n = 183; P < .0001). Academic Research Consortium (ARC) criteria were used to define MI in the intention-to-treat analysis, whereas WHO criteria were used in the per-protocol analysis, which likely drove the difference in MACE rates, Kandzari noted.

Through 3 years, the researchers had follow-up data on annualized rates of MACE, MI, total MI and cardiac death for 84% of patients. When using ARC criteria to define MI, the rate of MACE events escalated from 18.5% in year 1 to 27.1% in year 3 and the rate of MI events escalated from 13.9% in year 1 to 18.1% in year 3. When using WHO criteria to define MI, the rate of MACE increased from 10% to 18.7%, but the rate of MI remained stagnant. The annualized rate of target vessel-related MI was about 1% per year after the first year of index revascularization, according to Kandzari.

Cumulative 3-year TLR rate was 9.2%, and between 1 and 3 years after the index revascularization, the rate of TLR was only 3.1%. Similarly, although cumulative rate of target lesion failure as defined by ARC criteria was 19.6% at 3 years, it was much more modest between 1 and 3 years of follow-up, Kandzari said.

The researchers also found that less than 50% of patients were adherent to dual antiplatelet therapy at 3 years.

“This is an important perspective because against the background, there were no events of stent thrombosis beyond the first year of the index revascularization, including no definite events of stent thrombosis beyond the first 30 days of the index revascularization and no definite or probable events occurring in this patient population beyond the first 3 months of index revascularization,” Kandzari said.

“The results demonstrated sustained long-term safety and effectiveness of EES, specifically the Xience DES in this trial, for CTO revascularization, and in many ways, they still represent a standard of comparison for future technologies in CTO revascularization.” – by Melissa Foster

Reference:

Kandzari D. Three-year outcomes from the EXPERT CTO trial. Presented at: Chronic Total Occlusion Summit; Feb. 23-24, 2017; New York.

Disclosure: The study was sponsored by Abbott Vascular. Kandzari reports receiving grant or research support and/or consultant fees or honoraria from Abbott Vascular, Biotronik, Boston Scientific, Medtronic CardioVascular, Micell and St. Jude Medical.