Randomized clinical trial comparing a rivaroxaban-based with an antiplatelet-based strategy for cerebral embolization after TAVR (EARTH TAVR)-a magnetic resonance imaging substudy of the GALILEO trial

Abstract

Abstract Background Cerebral embolization in patients after Transcatheter Aortic Valve Replacement (TAVR) represents a serious complication, that was related to impaired bioprosthetic leaflet motion and new-onset atrial fibrillation (AFib). Purpose Hereafter we present the first randomized study comparing the effect of an anticoagulation plus antiplatelet with a dual antiplatelet antithrombotic treatment in patients after TAVR on cerebral embolizations as assessed by serial cerebral magnetic resonance imaging (MRI). Methods The Evaluation of Cerebral Thrombembolism After TAVR (EARTH - TAVR) study was conducted as an investigator initiated substudy of the multicenter, randomized, GALILEO study. After successful TAVR, patients without indication for chronic anticoagulation were randomly assigned to rivaroxaban 10mg plus acetylsalicylic acid 75–100mg once-daily or clopidogrel 75mg plus acetylsalicylic acid 75–100mg once-daily. Cerebral MRI scans were performed pre-TAVR as a baseline, post-TAVR (within 24–48 hours after TAVR) and 90 days after TAVR. The MRI protocol included diffusion-weighted (DWI) and fluid-attenuated inversion recovery (FLAIR) imaging. Cerebral embolic lesions were evaluated by an independent cerebral MRI core lab. The primary outcome measure of this study was the occurrence and extent of cerebral embolizations as measured by total volume of new ischaemic cerebral lesions. Results 36 patients were enrolled in the EARTH and the GALILEO study. The DWI MRI scans revealed an increase of cerebral lesions and volume post-TAVR by a median of 4.75 (95% NBCI 2.1–8.9) and 0.26cm3 (95% NBCI 0.11–0.59). On FLAIR imaging, lesion number and volume increased by a median of 3 (95% NBCI 1.5–6) and 0.1 cm3 (95% NBCI 0.04–0.31). At the 90 days MRI scan, there was no statistically significant change in cerebral lesions, if compared to the post-TAVR scan, irrespective of the treatment arm. Conclusion Thromboembolic events occur largely in the periinterventional phase post TAVR. Thereafter, the risk for additional cerebral embolization is low. An additional rivaroxaban therapy beyond antiplatelet inhibition did not impact on cerebral thromboembolism. Funding Acknowledgement Type of funding source: Private company. Main funding source(s): Bayer Pharmaceuticals