Trans-catheter Aortic Valve Implantation

We proposed to compare in an observational study procedural success at one month (VARC 3 criteria) and clinical and echographic follow-up at 6 months between 2 self expandable devices in TAVR : the supra annular Evolut device (Medtronic) vs the intra anular NAVITOR device (Abott)

The goal of this clinical trial is to evaluate the feasibility, effectiveness, and safety of pre-emptive left atrial veno-arterial extracorporeal membrane oxygenation (LAVA-ECMO) in patients undergoing complex and high-risk transcatheter aortic valve replacement (TAVR). These patients include adults with severe aortic stenosis who are hemodynamically unstable or at risk of instability due to anatomical complexity. The main questions it aims to answer are: 1. Does pre-emptive LAVA-ECMO reduce the incidence of in-hospital death, intraprocedural cardiac arrest, or emergent cardiac surgery? 2. What are the safety outcomes related to LAVA-ECMO, including major vascular, bleeding, or cardiac structural complications? -This is a single-arm, prospective, multi-center study with no comparison group. Participants will: * Be screened for eligibility based on hemodynamic status and anatomical complexity * Undergo pre-emptive LAVA-ECMO cannulation prior to or during TAVR * Receive follow-up assessments at 30 days and 1 year, including clinical evaluation and echocardiography

Purpose of the Study The purpose of this study is to investigate how a transcatheter aortic valve (TAVI, biological valve prosthesis) can best be positioned in order to avoid blockage of the coronary arteries by the valve material after implantation. Method The study will include patients undergoing TAVI. Participants will be randomized, meaning that it will be determined by chance which of two established implantation techniques is used. Both techniques are already part of routine clinical practice. Examinations After the procedure, a CT scan will be performed to evaluate the position of the valve in relation to the coronary arteries. This CT scan is the only additional examination beyond today's standard clinical practice. Significance If one of the techniques proves to provide better positioning of the valve, this method may be recommended as standard practice in future treatment. The study will therefore contribute to improved patient safety and treatment quality, as well as increase knowledge about optimal positioning and implantation techniques in TAVI.