Page 35 - Journal of Structural Heart Disease Volume 1, Issue 3

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Original Scientific Article
Video 3. In vitro Video showing a custom-made retrievable stent. (Zegdi et al, JACC. 2006;48:1365-8).
in seven patients and TEE in three patients. Balloon sizing of the prosthesis was performed in all patients, no prestenting was described. All patients underwent successful implantation of a 22-mm Melody valve with satisfactory results. No periprocedural death, stent fracture or valve embolization was observed. During follow up, two patients had vascular compli- cations (femoral artery pseudo aneurysm and femo- ral vein phlebitis) and one patient was operated for a Melody valve thrombosis due to heparin-induced thrombocytopenia.
Despite the promising results of the percutaneous tricuspid valve-in-valve implantation, a case series describing early failure of Melody and Sapien valves in the tricuspid position was recently published [24]. Authors describe four procedures in three patients where implantation of percutaneous valves within bioprosthetic tricuspid valves was performed with excellent immediate post procedural results. How- ever, in all four cases evidence of rapid valve failure within 2 weeks following intervention in three of the four cases and later in the fourth case was described. Two patients required surgical explantation and sub- sequent examination of the prosthesis showed de- generation with thickening and contraction of the leaflets. Routine blood tests including immunologi- cal and inflammatory markers were normal without evidence of endocarditis. Authors suggested that individual factors and/or hemodynamic conditions
Video 4. Video showing the valve in valve concept in tricuspid position in a sheep. A regurgitant bioprosthetic valve is surgically placed (Zegdi et al, JACC. 2006;48:1365-8).
associated with dilated poorly contractile right atria leading to limited valve leaflet mobility may explain this rapid deterioration; however these observations remain partially unexplained. We observed similar findings in failing Fontan patients receiving a Melody in the Fontan circulation [25].
The primary indication for tricuspid valve-in-valve implantation remains a key point of this procedure. If the predominant lesion of the bioprosthetic valve is stenosis (with or without regurgitation), the procedure may be then performed using standard technique. The size of the original surgical valve is not important. The only burning question in that situation is to know if the stenosis could be opened enough to reduce the transvalvular gradient. Recently, a Spanish team reported the successful implantation of a 29-mm Edwards-SAPIEN XT prosthesis within a 31-mm stenotic tricuspid bioprosthesis through a transfem- oral approach [26]. The procedure was carried out without predilatation or balloon sizing of the bio- prosthesis. Prestenting is rarely performed during tri- cuspid valve in valve implantation. This is in contrast with percutaneous pulmonary valve implantation where pre-stenting is most of the time necessary to create a stable landing zone and to prevent stent frac- ture in the right ventricular outflow tract. However, as the tricuspid valve is in general far away from right ventricular muscular bands as well as from the ster- num, valved stent fracture is not a major issue in the
Jalal, Z. et al.
Transcatheter Tricuspid Valve Therapies