Can Patients With Atrial Fibrillation Safely Discontinue Anticoagulant Therapy After Cardiac Surgery? (ATLAAC)

Anticoagulant Therapy in Patients With Atrial Fibrillation After Surgical Left Atrial Appendage Closure: a Randomized Non-inferiority Trial (The ATLAAC Trial)

Left atrial appendage (LAA) closure has become a frequent addition to oral anticoagulation in patients with atrial fibrillation who undergo cardiac surgery. The procedure significantly reduces the risk of stroke and systemic embolism, which may render anticoagulation unnecessary or even harmful when considering the associated increased risk of bleeding. A clinical trial to address the need for anticoagulation after LAA closure is needed.

The ATLAAC trial will enroll 1220 patients with atrial fibrillation who have previously undergone surgical LAA closure. Patients will undergo a cardiac CT-scan to determine if LAA closure was successful and patients with successful closure will be randomized to continue or discontinue anticoagulation. The trial will assess the risk of ischemic stroke, peripheral arterial embolism, and major bleeding during the randomized intervention

Inclusion Criteria:

• Age > 18 years
• Previously undergone any type of cardiac surgical procedure including any type of surgical LAA closure (use of any of the following techniques; amputation and suture closure, stapler closure, non-amputating suture closure or closure with an approved surgical occlusion device (e.g. AtriClip)) according to the NationalPatient Register (NPR), the Danish Heart Registry (DHR) or the Western Danish Heart Registry (WDHR) from January 1st 2010 til 3 months prior to inclusion in the project.
• Documented history of paroxysmal, persistent, or permanent atrial fibrillation or atrial flutter according to the electronic patient record
• Informed consent

Exclusion Criteria:

• Not receiving OAC (warfarin/DOAC)
• Patient specific conditions requiring OAC (e.g.mechanical valve, previous pulmonary embolism)
• Renal impairment (estimated glomerular filtration rate < 30)
• Allergy to contrast media
• Pregnancy or breastfeeding