Personalized, CT-guided Antithrombotic Therapy Versus Lifelong Single Antiplatelet Therapy to Reduce Thromboembolic and Bleeding Events in Non-atrial Fibrillation Patients After Transcatheter Aortic Valve Implantation

Personalized, CT-guided Antithrombotic Therapy Versus Lifelong Single Antiplatelet Therapy to Reduce Thromboembolic and Bleeding Events in Non-atrial Fibrillation Patients After Transcatheter Aortic Valve Implantation: a Pragmatic, International, Multicentre, Randomized Clinical Trial

The POPular ATLANTIS trial aims to investigate CT-guided antithrombotic therapy compared to lifelong single antiplatelet therapy after a transcatheter aortic valve implantation (TAVI) procedure. Only patients without an indication for anticoagulants will be included in this trial. Currently, lifelong single antiplatelet therapy (mostly aspirin) is considered the standard of care for these patients. However, this approach poses a bleeding risk with only a minimal reduction in thromboembolic events.

After 3 months, a CT scan will be conducted to assess the presence of thrombosis on the newly implanted TAVI valve. Based on the results of a 4D CT scan, the decision will be made whether the patient should receive no anticoagulant or antithrombotic therapy with apixaban. CT-guided antithrombotic therapy holds the potential for a greater reduction in thromboembolic events without increasing the bleeding risk.

Inclusion Criteria:

• Successful TAVI (according to the VARC-3 criteria)10 with any approved device
• Ability to understand and to comply with the study protocol
• Written informed consent

Exclusion Criteria:

• Existing indication for oral anticoagulation (e.g. atrial fibrillation, obstructive valve thrombosis detected by echocardiography prior to inclusion)
• Existing indication for dual antiplatelet therapy at three months after TAVI (rare at this time point)
• Creatinine clearance <15 mL/min (based on the CKD-EPI formula) or on renal replacement therapy