Comparison of Left Atrial Appendage Occlusion vs Standard Medical Therapy in Patients in AF Undergoing TAVI

Study category and Rationale Clinical study, Category A. Clinical Phase: Post market study Background and Rationale: Left atrial appendage occlusion (LAAO) allows avoiding oral anticoagulation and provides at the same time an at least equally good protection from strokes and peripheral embolism. It may therefore be an attractive alternative to oral anticoagulation in the patient population undergoing transcatheter aortic valve implantation (TAVI): the concept of LAAO is based on the fact that thrombus formation in atrial fibrillation occurs in \>90% in the left atrial appendage (LAA). Mechanical occlusion of the LAA reduces the stroke risk by eliminating the source of thrombus formation. In the here proposed "Randomized Comparison of Left Atrial Appendage Occlusion versus Standard Medical Therapy in Patients in Atrial Fibrillation Undergoing Transfemoral Transcatheter Aortic Valve Implantation", study we test the hypothesis, that LAAO is superior to standard medical therapy in the high-risk TAVI population. This hypothesis has not been investigated by previous studies so far. Overall Objective(s): Overall objective: to compare the safety (and efficacy) of LAAO using the St. Jude left atrial appendage closure device with standard medical therapy in a prospective, multi-center, randomized trial in patients undergoing TAVI in routine clinical practice. Primary Objective: To assess the safety of the device intervention with regard to stroke prevention and prevention of bleeding complications in a patients population at high risk of stroke and bleeding. Secondary Objectives: Short-term (procedural) safety of device intervention is assessed (rate of successful deployment of a left atrial appendage occluder; rate of kidney failure). As a further secondary objective, long-term effects of device intervention on stroke and bleeding prevention as well as mortality are assessed and compared to medical therapy. Outcome(s): Primary: Composite endpoint of ischemic and hemorr