麻豆传媒

This article is a collaboration between 麻豆传媒 and:

DENVER -- Two bioabsorbable-polymer drug-eluting stents (DES) hold promise for shortening dual antiplatelet therapy (DAPT) regimens after stenting, investigators showed at the (TCT) meeting here.

SENIOR

One was the Synergy DES, with 74 μm struts and a bioabsorbable everolimus-eluting polymer synchronizing drug release and polymer absorption. This device was better than bare metal stents (BMS) for percutaneous coronary intervention (PCI) in the elderly, according to the SENIOR trial.

Combined rates of all-cause mortality, MI, stroke, and ischemia-driven target lesion revascularization reached 16.4% in the BMS group and 11.6% in DES at the end of the first year after PCI (RR 0.71, 95% CI 0.52-0.94).

SENIOR included 1,200 patients older than 75 years with coronary artery disease who had DAPT duration tailored to either 1 month or 6 months (clopidogrel [Plavix] was the drug chosen most of the time). Participants were then randomized to the Synergy DES or a similar thin-strut BMS.

The difference between groups seemed to be driven primarily by revascularization (5.9% versus 1.7%, P=0.0002), with patients sharing similar rates of the other endpoints, reported Olivier Varenne, MD, PhD, of Hôpital Cochin in Paris.

As for safety, bleeds and stent thrombosis occurred at indistinguishable rates between BMS and DES groups.

"BMS should no longer be used as a strategy to reduce DAPT duration in elderly patients," Varenne concluded.

At a press conference, discussant Dean Kereiakes, MD, of The Christ Hospital in Cincinnati, said he agreed that BMS has no place in PCI for the elderly. "This is one more nail in the coffin of BMS. Now we have at least four clear-cut randomized trials where BMS was found to be less safe and less effective."

Moderator Gary Mintz, MD, of New York's Cardiovascular Research Foundation, was cautiously on-board as well. While "there are crazy exceptions," he suggested that 99.9% of the time BMS is not the right device.

"I go to Asia a lot. I can tell you China no longer has BMS," Mintz told the audience.

As for Varenne, he said that his lab stopped implanting BMS 4 months ago.

SENIOR participants comprised a population at high ischemic risk, with 75% having hypertension, 52% having hypercholesterolemia, and 26% having diabetes. Roughly 55% presented with stable angina and silent ischemia, another quarter with non-ST-segment elevation MI, and the rest were roughly split between unstable angina and ST-segment elevation MI.

The study was published online in .

HARMONEE

The bioabsorbable Combo stent -- a luminal CD34+ antibody-coated, sirolimus-eluting product designed to capture endothelial progenitor cells -- was found to be non-inferior to the durable-polymer Xience everolimus-eluting stent (EES) in the Japan-USA HARMONEE study.

Also presented at TCT, the study data showed that among the 572 patients randomized to either device across Japan and the U.S., rates of 1-year target vessel failure (combined cardiac death, target vessel MI, and ischemia-driven target vessel revascularization) were comparable between groups: 7.0% with the Combo stent and 4.2% with Xience. The former met non-inferiority in this aspect (P=0.020 for non-inferiority), but this analysis was underpowered due to the better-than-expected performance of EES.

Furthermore, optical coherence tomography (OCT) suggested better healthy tissue coverage and a higher proportion of homogeneous neointimal tissue after Combo placement (81.2% versus 68.8%), perhaps indicative of the role that endothelial progenitor cell capture plays, according to Mitchell Krucoff, MD, of Duke University Medical Center in Durham, North Carolina.

"OCT suggests an active mechanistic role of endothelial progenitor cell technology in vivo, including superior healthy tissue strut coverage with Combo vs. EES and more homogeneous tissue qualitatively with Combo vs. EES," he said.

By 1 year, late lumen loss and restenosis assessed by quantitative coronary angiography occurred to similar extents between Combo and Xience groups.

REDUCE

The same Combo stent also allowed patients to reduce the time they spent on DAPT.

The REDUCE study had 1,496 patients with acute coronary syndrome (ACS) randomly assigned to 3-month or 12-month DAPT after receipt of the bioabsorbable-polymer stent.

At 12 months, the composite endpoint of all-cause death, MI, stent thrombosis, stroke, target vessel revascularization, and bleeding was equally likely between groups (8.2% for 3-month versus 8.4% for 12-month DAPT, OR 0.97, 95% CI 0.67-1.41, P<0.001 for non-inferiority), according to Harry Suryapranata, MD, PhD, of the Radboud Institute for Molecular Life Sciences in The Netherlands.

"This finding is consistent for all pre-specified subgroups," the presenter said at TCT. "Therefore, a shorter DAPT strategy could be considered, if necessary, even in ACS population."

Individual endpoints gave neither group an advantage. Notably, however, there were numerical signals that 3-month DAPT was associated with more all-cause mortality (1.9% versus 0.8%, P=0.07) and stent thrombosis over follow-up (1.2% versus 0.4%, P=0.08).

Suryapranata attributed the mortality and stent thrombosis trends to chance, emphasizing at the same press conference that half of deaths in the short-DAPT arm were caused by cancer and that no statistical significance was reached.

"I might inject a note of caution. Absence of difference doesn't mean no difference," commented Kereiakes. "In a trial this size, I still have concerns that it's underpowered to be definitive for these endpoints."

In REDUCE, prasugrel (Effient) and ticagrelor (Brilinta) were preferred over clopidogrel, but the choice of P2Y12 inhibitor was ultimately up to each clinician.