Comparison of apixaban versus aspirin for the prevention of latent bioprosthetic aortic valve thrombosis: study protocol for a prospective randomized trial

Scientific paper - Original scientific paper

• Author: Tomislav Kopjar
• Author: Hrvoje Gašparović
• Author: Maja Hrabak Paar
• Author: Daniel Lovrić
• Author: Petra Čerina
• Author: Tomislav Tokić
• Author: Davor Miličić
• Author's institution: University of Zagreb; School of Medicine; (Department of Internal Medicine)
• Author's institution: University of Zagreb; School of Medicine; (Department of Surgery)
• Author's institution: University of Zagreb; School of Medicine; (Department of Radiology)
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Internal Medicine
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Surgery
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Radiology

Abstract (english)

Background: The optimal antithrombotic strategy early after aortic valve replacement surgery with a biological valve remains controversial due to lack of high-quality evidence. Either oral anticoagulants or acetylsalicylic acid should be considered for the first 3 months. Hypo-attenuated leaflet thickening on cardiac computed tomography has been associated with latent bioprosthetic valve thrombosis and may be prevented with anticoagulation. We hypothesize that anticoagulation with apixaban is superior to single antiplatelet therapy with acetylsalicylic acid in reducing hypo-attenuated leaflet thickening of bioprosthetic aortic valve prostheses.

Methods: In this prospective, open-label, randomized trial, patients undergoing isolated aortic valve replacement surgery with rapid deployment bioprosthetic valves will be randomized. The treatment group will receive 5 mg of apixaban twice a day for the first 3 months and 100 mg of acetylsalicylic acid thereafter. The control group will be administered 100 mg of acetylsalicylic acid once a day, indefinitely. After the 3-month treatment period, a contrast-enhanced electrocardiogram-gated cardiac computed tomography will be performed to identify hypo-attenuated leaflet thickening of the bioprosthetic valve. The primary objective of the study is to assess the impact of apixaban on the prevention of hypo-attenuated leaflet thickening at 3 months. The secondary and exploratory endpoints will be clinical outcomes and safety profiles of the two strategies.

Discussion: Antithrombotic therapy after aortic valve replacement is used to prevent valve thrombosis and systemic thromboembolism. Latent bioprosthetic valve thrombosis is a precursor of clinically significant prosthetic valve dysfunction or thromboembolic events. The hallmark feature of latent bioprosthetic valve thrombosis is hypo-attenuated leaflet thickening on cardiac computed tomography. Subclinical leaflet thrombosis occurs frequently in bioprosthetic aortic valves, more commonly in transcatheter than in surgical valves. There is no evidence on the effect of direct oral anticoagulants on the incidence of hypo-attenuated leaflet thickening after surgical aortic valve replacement with rapid deployment bioprostheses.

• Keywords (english): Antithrombotic therapy; Aortic valve replacement; Biological valve; Hypo-attenuated leaflet thickening; Rapid deployment valve; Reduced leaflet motion; Sutureless valve; Valve thrombosi
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review
• Publication version: Published version
• Journal title: Trials
• Numbering: vol. 25, no. 1, 324
• e-ISSN: 1745-6215
• DOI: https://doi.org/10.1186/s13063-024-08175-w
• URN:NBN: urn:nbn:hr:105:140422
• Publication: 2024-05-16
• Document URL: https://trialsjournal.biomedcentral.com/articles/10.1186/s13063-024-08175-w
• Type of resource: Text
• Access conditions: Open access
• Created on: 2025-02-18 08:20:14