In vitro evaluation of implantation depth of valve-in-valve (Inovare-Bovine Pericardium Bioprosthesis) in pressure gradient

• Grant number: 17/09699-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2017
• End date: July 31, 2018
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Diego Felipe Gaia dos Santos
• Grantee: Gabriel Alencar de Oliveira
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Aortic Stenosis is most prevalent valvular pathology in the western world, affecting mostly elderly people. It shows great mortality rates after the symptoms start, with poor results from the drug therapy. The surgical therapy presents good results, but there is a group of patients with which the high risk can constitute an hindrance due to the associated high morbi-mortality. For these patients is being indicated the transcatheter aortic valve implantation (TAVI) as an alternative to the surgical procedure. In patients with previous bioprosthesis implant, a valve-in-valve method of transcatheter aortic valve replacement has been proposed, showing to be more safe but with tendency to higher gradients, when compared to the native ring implant, being able to compromise the result. The valve-in-valve TAVI is associated to lower effective valvar orifice areas due to its insertion inside a rigid and inflexible ring. This reflects in higher gradients and possibly can compromise the clinical result and the graft durability. Variations in implant position can determine effective area and transvalvar gradient alterations. We seek to determine the best point of Inovare® (Braile Biomédica®) prosthesis implant position when used in the valve-in-valve technique in relation to the pressure gradient. Multiple clinical combinations of valve-in-valve settings will be testes with different implant positions (depths) in a pulse duplicator. The hydrodynamic pressure gradients of Inovare® (Braile Biomédica®) bioprosthesis of different diameters will be measured in different heights of insertion in relation to the ring of bovine pericardium bioprosthesis (Braile Biomédica®). The prosthesis will be paired according to the bovine prosthesis diameter and its corresponding TAVI, obeying the technically appropriate over-sizing. (AU)