Cerebral Regional Oxygen Saturation During TAVI - The CROS-TAVI Prospective Registry

Overview

This single-center, non-commercial clinical study investigates how different types of transcatheter aortic valve prostheses affect cerebral oxygen saturation during the procedure (TAVI - Transcatheter Aortic Valve Implantation). The study uses a non-invasive monitoring system (NIRS) to track brain oxygenation (rSO₂) in real time. The goal is to understand whether balloon-expandable, intra-annular self-expanding, or supra-annular self-expanding valves lead to different levels or patterns of cerebral oxygenation. This may help identify early warning signs for delayed hemodynamic recovery, stroke, or delirium. Participants will be randomly assigned to receive one of: A balloon-expandable valve (Group A), or A self-expanding valve (Group B), with further randomization into: Group B1: intra-annular valve (NAVITOR) Group B2: supra-annular valve (EVOLUT) The procedure, follow-up, and data collection will follow standard clinical practice. No experimental devices or drugs are used. Patients will not undergo any additional risk or burden beyond what is normally expected during TAVI. The study is being conducted at the Fondazione Policlinico Universitario A. Gemelli IRCCS in Rome, Italy, and aims to enroll 40 patients. No compensation is provided, and participation is voluntary.

This is a prospective, randomized, single-center, interventional clinical study conducted at the Fondazione Policlinico Universitario A. Gemelli IRCCS in Rome, Italy. The study aims to investigate differences in cerebral regional oxygen saturation (rSO₂) during transcatheter aortic valve implantation (TAVI) using different transcatheter heart valve (THV) technologies. Aortic valve stenosis (AVS) is the most common valvular disease in the elderly, and TAVI has become a widely accepted therapeutic option in high-, intermediate-, and low-risk patients. However, the rapid ventricular pacing, balloon dilatation, and valve deployment involved in TAVI may induce transient cerebral hypoperfusion. This study utilizes near-infrared spectroscopy (NIRS) as a non-invasive method to monitor cerebral oxygenation in real-time during the procedure. The primary objective is to evaluate the variation in rSO₂ during specific procedural phases and determine whether the type of valve used (balloon-expandable vs. self-expanding) impacts cerebral perfusion. A secondary aim is to identify a potential threshold value of rSO₂ below which prolonged hemodynamic recovery may occur. The study also explores the association between cerebral desaturation and clinical outcomes such as in-hospital mortality, stroke, and postprocedural delirium. Patients with symptomatic severe aortic stenosis meeting specific inclusion/exclusion criteria will be enrolled and randomized 1:1 to receive: Group A: A balloon-expandable valve (SAPIEN platform, Edwards Lifesciences) Group B: A self-expanding valve (SEV) Patients in Group B will be further randomized to receive: Group B1: Intra-annular SEV (NAVITOR, Abbott) Group B2: Supra-annular SEV (EVOLUT, Medtronic) Cerebral rSO₂ will be monitored bilaterally using INVOS 5100C NIRS sensors placed on the forehead. Measurements will be recorded at six procedural time points: baseline (pre-induction), start of procedure, during pre-dilatation (if performed), at valve deployment, at the lowest rSO₂ during deployment, post-dilatation (if performed), and end of procedure. Neurocognitive status will be assessed pre-procedure using the Mini-Mental State Examination (MMSE). Postoperative delirium will be monitored using the CAM-ICU and RASS scales. Clinical and procedural data, including rapid ventricular pacing parameters, valve type, and any need for resheathing, will also be recorded. The primary endpoint is the comparison of mean nadir rSO₂ values between balloon-expandable and self-expanding valve groups. Exploratory analyses will evaluate differences among all three groups (A, B1, B2). Secondary endpoints include in-hospital death, stroke, and delirium incidence. A total of 40 patients will be enrolled (20 in Group A, 10 in B1, 10 in B2). The study is no-profit, does not involve investigational drugs or unapproved devices, and all THVs used are CE-marked and clinically approved. The protocol has been approved by the local ethics committee (CET Lazio Area 3, ID 7257). The findings of this study may provide novel insights into the role of cerebral oxygenation monitoring during TAVI and contribute to optimizing valve selection and procedural strategies to improve neurologic and hemodynamic outcomes.