In-Vitro functional analysis of reconstructive techniques in mitral valve surgery on patient-specific 3D replicas using a high-fidelity flow simulator

• Applicant: Dr. Gabriele Romano
• Subject Area: Cardiac and Vascular Surgery
• Term: from 2022 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 499174208

Mitral regurgitation is one of the most common valve diseases in Europe today. Its incidence increases with age. The mitral valve is a highly complex apparatus and the proper functioning is enabled by the co-ordinated interaction of its various structures. Several surgical and transcatheter techniques can repair the mitral valve apparatus in case of insufficiency. Surgical reconstruction of the mitral valve is now the technique of choice among patients who can undergo surgery. Although these techniques have been in use for three decades, mitral valve reconstruction remains a challenge for the surgeon, as the functional mechanisms and pathomorphologies are not completely comprehended. Similarly, the absence of quantitative data to evaluate the different surgical techniques currently in use makes the surgery rather depended on the experience of the operator therefore results in an overall empirical approach. This research project seeks to clarify the effects of the most commonly used surgical techniques for a specific mitral valve lesion, posterior leaflet prolapse at segment 2 (P2 prolapse), by means of in-vitro surgical experimentation carried out on replicates of patient-specific pathological mitral valves made of silicon.Through the use of a specific dynamic simulator, it is possible to test the replicates before and after reconstruction in a left heart model with a pulse duplicator. Thanks to the presence of pressure and flow detectors and the concomitant echocardiographic examination, it would possible analyse specific quantitative aspects, such as trans-mitral gradient, flow variation during the cardiac cycle, pressure variation in the chambers and coaptation area, among others. The valves can be tested in different haemodynamic settings, simulating clinical situations at rest and during exercise.Main objective is to quantitatively analyse different surgical techniques using the replicated models. The advantage of in-vitro experimentation in this field is the possibility to operate on the same valve defect several times, quantitatively comparing the effects of the surgery performed on the complex valve apparatus.The central value of this experimentation is to transfer information from in-vitro experimentation in the clinic, to potentially assist surgeons for intraoperative choices in the future. This research aim is to achieve an anatomical and functional knowledge of the mitral valve based on quantitative evaluations in order to make this surgery more reproducible and less empirical.

• DFG Programme: Research Grants