Leaflet Thickening and Motion After Transcatheter Aortic Valve Replacement: Design and Rationale of the Rotterdam Edoxaban Trial

Abstract

Background: Multislice computed tomography (MSCT) may reveal hypo-attenuated leaflet thickening (HALT) and/or reduced leaflet motion (RELM) in approximately 15 % of patients after transcatheter aortic valve replacement (TAVR). These supposedly thrombogenic phenomena may be associated with neurological events and increased transprosthetic gradients. It is unclear whether oral anticoagulant therapy -specifically a factor Xa inhibitor- could affect the incidence of HALT/RELM.

Study design: The Rotterdam EDOXaban (REDOX) trial is an investigator-initiated, single-center, prospective registry in which 100 patients with no formal indication for oral anticoagulant drugs or dual antiplatelet therapy, will receive a 3-month treatment with edoxaban, followed by a MSCT to detect HALT/RELM. The primary endpoint is the incidence of HALT at 3-months follow-up. Secondary endpoints include the incidence of RELM at 3 months; change in transprosthetic gradients at 1 year and the clinical composite endpoint of all-cause death, myocardial infarction (MI), ischemic stroke, systemic thromboembolism, valve thrombosis and major bleeding (International Society on Thrombosis and Hemostasis [ISTH] definition) at 1 year follow up. The study is powered to demonstrate with 90 % statistical power and a 0.025 alpha a 4 % incidence of HALT with edoxaban as compared to the expected 15 % rate with an antiplatelet regimen and will enroll 100 patients to account for loss of follow-up or CT-drop out.

Conclusion: The REDOX trial will investigate the short-term effect of an Xa-inhibitor on the incidence of HALT after TAVR. (ClinicalTrials.gov Identifier: NCT04171726).

Keywords: Computed tomography; HALT; RELM; Transcatheter aortic valve replacement.