A good day for switched DAPT, MiStent, the Lotus valve and deferral with iFR and FFR
The late breaking trials and trial updates session showcased up-to-the-minute data from the TOPIC study of platelet inhibition following acute coronary syndrome and the DESSOLVE III randomised comparison of the MiStent and Xience drug-eluting stents, as well as a pooled analysis of the DEFINE FLAIR and IFR SWEDEHEART trials investigating revascularisation deferral with both iFR and FFR, and data from the REPRISE III comparison of Lotus and CoreValve.
The TOPIC randomised study investigated the benefit of switching dual anti-platelet therapy (DAPT) after acute coronary syndrome (ACS). According to Thomas Cuisset, initial DAPT strategy after ACS should be P2Y12 blockers prasugrel and ticagrelor. The study found that in patients without adverse events during the first month post ACS treated with PCI, the switched DAPT strategy was superior to unchanged DAPT strategy to prevent bleeding complication without increased ischaemic event risk. The study patients were ACS patients undergoing PCI who were free of major adverse cardiac events (MACE) one month after PCI and treated with aspirin and prasugrel or ticagrelor.
“We observed a significantly lower incidence of the primary endpoint in the group of patients randomised to switch DAPT strategy compared to the unchanged strategy. This difference in the primary endpoint was not related to difference in ischaemic events—as the rate of ischaemic complication was not different—but related to a significant reduction of bleeding complication with the switched DAPT strategy compared to the unchanged DAPT. We observed a better prognosis with switched DAPT with less bleeding and no difference in MACE,” T. Cuisset reported.
He added that these results could provide a new strategy integrating the dynamic risk after ACS with potent DAPT in the early phase to prevent early ischaemic events. Cost reduction is also an important implication.
Results from the DESSOLVE III trial presented by Robbert de Winter show that the MiStent device (Stentys) is non-inferior to the Xience stent (Abbott) at 12 months in a real-world, all-comers population. The study was a randomised comparison of the Xience polymer everolimus-eluting stent vs. MiStent which releases embedded sirolimus microcrystals from the vessel wall. DESSOLVE III included 1,398 patients from 20 sites in four European countries.
“At one-year the incidence of target lesion failure was 5.8% for the MiStent and 6.5% for the Xience. The non-inferiority hypothesis was met with p<0.001,” R. de Winter reported.
He added, “MiStent was non-inferior to the Xience stent for target lesion failure at 12 months. There were no statistical differences across the stratified analyses and sub groups, supporting the hypothesis that long-term cytostatic inhibition of early neointima could prevent the late neointimal growth seen in the medium and long term with a conventional drug-eluting stent.”
Deferral safe with both iFR and FFR
According to a pooled analysis of the DEFINE FLAIR and IFR SWEDEHEART trials presented by Javier Escaned, coronary revascularisation deferral is safe with both iFR and FFR. The analysis investigated if one-year outcomes of deferred patients are similar when the decision is based on FFR or iFR measurements and whether the decision is influenced by clinical presentation (stable coronary disease [SCD] or ACS). The primary endpoint was MACE rate (composite of death, non-fatal myocardial infarction and unplanned revascularisation) at one year.
“We found consistent agreement with earlier trials in that decision making using iFR results in treating fewer and deferring more patients—45% of FFR patients were deferred vs. 50% with iFR. The good news is that the long-term outcomes of these patients are excellent with a 4% MACE rate at one year, about half that observed in the DEFER study, and identical with iFR and FFR. This suggests that although iFR defers more patients, they do as well as if you defer with FFR,” J. Escaned explained.
For ACS, J. Escaned reported interesting results: “In deferred patients, clinical presentation makes a difference in terms of long-term events, so it was clear there were significantly more events in patients deferred when presenting with ACS compared with SCD. There is room for improvement and it has to come from understanding what is happening in ACS patients,” he said.
REPRISE III trial data presented by Ted Feldman indicate that the Lotus valve is non-inferior to the CoreValve for one-year safety and effectiveness. REPRISE III is a global, prospective, multicentre, randomised, controlled, non-inferiority trial comparing safety and effectiveness with the Lotus valve versus the self-expanding CoreValve in patients at extreme or high surgical risk.
The trial randomised 912 patients in a 2:1 ratio to Lotus valve (607) or CoreValve (305). According to T. Feldman, the primary effectiveness endpoint (one-year composite of all death, disabling stroke and moderate or greater paravalvular aortic leakage [PVL]) was lower with Lotus compared to CoreValve (16.7% vs. 29%, p<0.001). The Lotus valve also demonstrated non-inferiority to CoreValve for the primary safety endpoint—a composite of all mortality, stroke, life-threatening and major bleeding events, stage 2/3 acute kidney injury or major vascular complications through 30 days.
The pre-specified secondary endpoint demonstrated the Lotus valve had significantly lower rates of moderate to severe PVL compared to CoreValve (2% vs. 11.1%, p<0.001).
“The Lotus valve is safe and effective compared to a commercially available self-expanding TAVI valve in this large randomised global trial,” T. Feldman concluded.