Rationale and design of REAC-TAVI 2: single antiplatelet treatment with ticagrelor versus aspirin after transcatheter aortic valve implantation

Abstract

Background: Patients undergoing transcatheter aortic valve implantation (TAVI) frequently experience life-threatening ischemic and bleeding complications. However, management of antithrombotic therapy after TAVI in patients without oral anticoagulation (OAC), particularly in patients with high burden for subsequent ischemic events, has limited evidence from randomized controlled trials.

Methods: The REAC TAVI2 trial is a prospective, multicenter, open-label, phase III randomized trial (NCT05283356). A total of 1206 patients undergoing TAVI with high ischemic risk (defined as concomitant coronary artery disease, diabetes mellitus or peripheral vascular disease) will be randomized in a 1:1 ratio to single antiplatelet therapy with aspirin (100mg once daily) or low-dose ticagrelor (60mg twice daily). The primary endpoint is the incidence of a net adverse clinical event (NACE) at 1-year after TAVI. NACE is defined as a composite of all-cause mortality, cerebrovascular events, myocardial infarction, progressive angina leading to emergency evaluation, rehospitalization or new coronary angiogram, clinical valve thrombosis, acute limb ischemia leading to hospitalization, and type 2, 3, or 5 bleeding. The secondary endpoint is the incidence of subclinical valve thrombosis detected by hypo-attenuated leaflet thickening and reduced leaflet motion at 3 and 12 months post-TAVI assessed by four-dimensional computed tomography.

Summary: In patients undergoing TAVI without an indication for OAC, there is a need for antiplatelet therapy that provides protection against ischemic events without increasing bleeding, particularly in the subset of patients at heightened risk of ischemic events. The REAC-TAVI 2 is a randomized multicenter clinical trial designed to study the effect of single antiplatelet therapy with aspirin compared to low-dose ticagrelor on a composite outcome of all-cause mortality, ischemic, and bleeding events after TAVI.

Keywords: Antiplatelet therapy; Aortic Valve Stenosis; Bleeding; Comorbidity; Stroke; Transcatheter Aortic Valve Replacement; randomized trial; trial design.