UniverSEAL III - Transcatheter Aortic Valve

Authors: Ngoc Nguyen, Vy Nguyen, Yen Nguyen

Advisor: Dr. Alessandro Bellofiore

Transcatheter Aortic Valve Implants (TAVI) have been developed as an alternative approach for patients who cannot undergo traditional open-chest Aortic Valve Replacement. During the TAVI procedure, the natural heart valve is replaced with a bioprosthetic valve, mounted on a collapsible stent frame, delivered through a cardiac catheter. However, paravalvular leakage (PVL) is a major postoperative issue with TAVI, and occurs if the prosthetic valve is not placed properly. PVL is responsible for unacceptably high levels of regurgitant (retrograde) flow during diastole. In this project we designed a novel sealant element that can be combined with any transcatheter aortic valve to reduce PVL. The sealant is made of a thin-wall and hollow ePTFE tube with hydrogel Extralink PEGDA injected inside. The main goal of this project is to further reduce PVL using the UniverSEAL III prototype, a custom-designed stent with a sealant chamber, in combination of different injected hydrogel volumes. In order to replicate realistic mechanical loading on the sealant, we designed a stent frame based on the popular Edward Sapien 3. We are currently testing for PVL of the sealant element mounted on the stent frame under hydrostatic pressure mimicking diastolic conditions (i.e. closed valve, no forward flow).