Rationale and design of the RE-LATED AF—AFNET 7 trial: REsolution of Left atrial-Appendage Thrombus—Effects of Dabigatran in patients with Atrial Fibrillation

Abstract

Background: Dabigatran etexilate, a direct thrombin inhibitor and non-vitamin K antagonist oral anticoagulant (NOAC), has been shown to effectively prevent thromboembolic events in patients with non-valvular atrial fibrillation (AF). However, there is a paucity of data on the antithrombotic efficacy and safety of dabigatran in the resolution of left atrial appendage (LAA) thrombi in AF patients. Objective: The primary objective of the RE-LATED AF trial is to assess whether dabigatran results in a faster complete LAA thrombus resolution as compared to vitamin K antagonist phenprocoumon. Secondary objectives are to assess the impact of dabigatran on complete LAA thrombus resolution rate within 6 weeks of treatment and change in LAA thrombus volume under treatment. Furthermore, this study aims to assess and compare safety and tolerability of dabigatran vs. phenprocoumon. Methods: The study is designed as a prospective, randomized, open-label, controlled, explorative, blinded endpoint (PROBE) trial. Patients with AF and left atrial appendage thrombus confirmed by transoesophageal echocardiography (TEE) will be randomized to receive either dabigatran (150 mg bid) or phenprocoumon (INR 2–3) for the resolution of LAA thrombus formation for at least 21 days. Thrombus resolution will be determined by TEE 3 weeks after treatment initiation and subsequently at weeks 4 and 6, if the LAA thrombus has not been resolved before. A total of 110 patients are planned to be randomized. Conclusion: This is the first prospective, multicentre, randomized controlled clinical trial investigating safety and efficacy of a NOAC for the resolution of LAA thrombi in patients with non-valvular AF.