Cardiogenic Shock, ECMO

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

Midazolam and propofol are the most used intravenous (IV) sedative agents, but their use is associated with well-known adverse effects such as accumulation, myotoxicity, tachyphylaxis, and unpredictable wake-up time. For benzodiazepines, an increased tolerance, possible accumulation after long-term use, and an increased risk of acute withdrawal syndrome are reported. In patients on extracorporeal membrane oxygenation (ECMO) for cardiogenic shock, the negative hemodynamic effects of these drugs are a particular matter of concern. Besides the extracorporeal circuit itself may affect the pharmacokinetics of these IV sedatives. Indeed, drug sequestration in ECMO circuits is a well-known phenomenon influenced by drug chemo-physical properties. Given the large surface area of tubing and membrane, considerable quantities of drugs used in ECMO patients may be sequestered over a period, resulting in a significant increase in their volume of distribution. Similarly, frequent hemodilution and organ dysfunction would also contribute to an increase in the volume of distribution. Propofol, which is lipophilic is significantly sequestrated in the circuit. Consequently, it is commonly observed that patients receiving ECMO have substantially higher sedative and analgesic drug requirements than patients without ECMO. To date, there is no ideal concept for analgesia and sedation of patients on ECMO in the ICU. A drug that sedates effectively but with minimal residual sedation after the end of the administration and without the aforementioned drawbacks of the current agents would be valuable. Interestingly, a recent randomized controlled non-inferiority trial that randomized 338 patients showed that, compared with propofol, sedation with inhaled anaesthetics was non-inferior. Sedation with inhaled anaesthetics resulted in a higher rate of spontaneous breathing and a shorter wake-up time after 48h of sedation. Indeed, inhaled sedation, which has been associated with reduced opioid consumption and less delirium in ICU patients, is a promising alternative to IV sedation. Moreover, inhaled anaesthetics might be associated with less myocardial injury and lower doses of inotropic support in patients undergoing cardiac surgery. However, to date, the experience with volatile agents remains limited in patients on ECMO. We hypothesized that the use of inhaled isoflurane with the Sedaconda anaesthetics conserving device (ACD) in cardiogenic shock patients on ECMO will reduce the mortality and increase the number of ventilation-free days at day 28 following ECMO onset compared to usual IV sedation by propofol and/or midazolam.