Page 40 - Journal of Structural Heart Disease Volume 1, Issue 3

Original Scientific Article
146
Video 7. Echographic Video after transcatheter valve implant showing correction of the regurgitation of the implanted bio- prosthetic surgical valve (Zegdi et al, JACC. 2006;48:1365-8).
with percutaneous tricuspid valve implantation in 8healthyewes.Thisprosthesisconsistedinaniti- nol self-expandable stent formed of two disks (40- mm diameter) separated by a tubular part (15-mm length, 18-mm diameter) containing a bovine jugu- lar vein valved segment. A polytetrafluoroethylene membrane was sutured outside of the ventricular disk to guarantee the sealing of the device. The di- ameter of the two disks was chosen to be slightly larger than the diameter of the tricuspid annulus to allow for anchoring (Figure 3 and Videos 8 to 11). Mechanical fixation was ensured by trapping the annulus between the two disks. In one animal, the device was trapped in tricuspid chordae, leading to its incomplete opening. A significant paravalvular leak was observed in one animal, due to a torn the PTFE membrane beside a weld fracture.
Other authors described a similar valved stent; a porcine pericardial valve mounted on a double-edge nitinol stent with satisfactory results in a chronic sheep model despite 2 device embolization upon 10 procedures [37].
Moreover, Iino et al. describe another device, a bo- vine pericardial valve mounted on a self-expandable nitinol stent with a super-absorbent polymer placed
Video 8. Video showing the delivery of a valved stent in tri- cuspid native valve. The delivery system is advanced over a wire in the right ventricle. The RV disk is slowly opened in the apex of the RV and pullback in the tricuspid annulus. The device is then completely opened and delivered (Boudjemline, JACC. 2005;46:360-5).
beneath the right atrial element for minimizing paravalvular leak. This device was successfully implanted in pigs through a mini-thoracotomy using trans-ventricular approach with a reduction of para- valvular leakage [38].
Although these papers opened perspectives into transcatheter orthotopic native tricuspid valve replace- ment, no further experimental developments or hu- man implantation were published with these devices.
Recently, Kefer et al. [39] published the first hu- man transcatheter implantation in a “native” tricuspid valve using a 26-mm Sapien® valve after failed multi- ple surgical repairs in a 47–year-old female. Tricuspid annulus size was assessed by magnetic resonance imaging, three-dimensional transesophageal echo- cardiography and especially low-pressure balloon siz- ing during the procedure. Prestenting was achieved by covered stent to create a rigid landing zone and to avoid paravalvular leak. As it is the case for VIR implantations, the dimensions of the tricuspid valve annulus were better approximated by the SAPIEN® valves than the Melody valves (maximum expandable diameter 22 mm). However, after first valve implanta- tion, severe paravalvular regurgitation was observed, related to a more apical position of the Sapien® valve.
Journal of Structural Heart Disease, August 2015
Volume 1, Issue 3: 137-151