Edoxaban Provides No Benefits on Stroke Risk vs DAPT Post-TAVR

Conference | <b>American College of Cardiology</b>

ADAPT TAVR found use of edoxaban vs DAPT resulted in a numerical reduction in SLT, but this did not reach statistical significance and did not contribute to a reduction in stroke or cerebral lesions.

Opting for edoxaban instead of dual antiplatelet therapy following transcatheter aortic valve replacement (TAVR) provides no benefit in terms of reducing new cerebral thromboembolism and neurological or neurocognitive function, according to the results of the ADAPT-TAVR trial.

Presented at the American College of Cardiology 71st Annual Scientific Sessions, results of the trial demonstrate use of edoxaban was associated with a numerical reduction in incidence of subclinical leaflet thrombosis (SLT), but this reduction did not reach statistical significance or result in reductions in risk for strokes or transient ischemic attack or declines in neurocognitive function.

“The key messages from this study are that SLT has not been proven to affect clinical outcomes for patients undergoing valve replacement and that in patients in whom SLT causes no symptoms or complications, its presence should not dictate the type of antithrombotic therapy that patients receive following the implantation of an artificial heart valve,” said Duk-Woo Park, MD, of Asan Medical Center in Seoul, Korea, in a statement. “Additionally, these findings do not support the routine use of computed tomography scans to detect SLT.”

With the relative recent introduction of TAVR, many questions persist around optimal post-TAVR treatment approaches. The ADAPT-TAVR trial was designed with the intent of assessing the effects of edoxaban compared against dual anti platelet therapy with clopidogrel plus aspirin on incidence of leaflet thrombosis, with an additional interest in exploring the relationship between SLT and cerebral thromboembolism was well as neurological or neurocognitive function.

A multicenter, open-label randomized trial, ADAPT-TAVR randomized 229 patients aged 18 years or older without an indication for long-term anticoagulation who had undergone successful TAVR for aortic stenosis in a 1:1 ratio to edoxaban or dual antiplatelet therapy, with 111 in the edoxaban arm and 118 in the dual antiplatelet therapy arm. This cohort had a mean age of 80.1 years, 58.1% were women, and the mean STS risk score was 3.3%. The primary outcome of interest for the study was incidence of leaflet thrombosis on four-dimensional CT at 6 months. Secondary outcomes of interest included new lesion number and volume on brain MRI as well as changes of neurological/neurocognitive function between 6-month and immediate post-TAVR.

Upon analysis, results indicated there was a trend toward lower condense of SLT in the edoxaban group compared to the dual antiplatelet therapy group, but this failed to reach statistical significance (9.8% vs 18.4%; absolute difference: -8.5% [95% CI, -17.8 to 0.8]; P=.076). Additionally, no differences were observed for percentage of patients with new cerebral lesions on brain MRI (edoxaban vs DAPT: 25.0% vs 20.2%; difference: 4.8% [95% CI, -6.4 to 16.0]), median total new lesion number, and lesion volume.

Further analysis demonstrated there were also no differences in the percentages of patients with worsening neurological and neurocognitive function. When assessing safety, investigators found there was no difference in rate of major bleeding events between the study arms and no significant association was observed for presence or extent of leaflet thrombosis with new cerebral lesions or changes in neurological or neurocognitive function.

“We saw no correlation between the number of occurrences of detectable SLT and the number of new signs of blood clotting in the brain or changes in cognitive function,” Park added.

This study, “Edoxaban versus Dual Antiplatelet Therapy for Leaflet Thrombosis and Cerebral Thromboembolism after TAVR,” was presented at ACC.22 and simultaneously published in Circulation.