Twin valve caval stent for functional replacement of incompetent tricuspid valve: a feasibility animal study.
OBJECTIVE
To evaluate feasibility of a twin valve caval stent (TVCS) for functional replacement of an incompetent tricuspid valve (TV) in an acute animal study.


METHODS
One swine and three sheep were used in the study. TVCS placement was tested in a swine with a normal TV. TVCS function was tested in three sheep with TV regurgitation created by papillary muscle avulsion. Cardiac angiograms and pressure measurements were used to evaluate TVCS function. Two sheep were studied after fluid overload.


RESULTS
TVCS was percutaneously placed properly at the central portions of the superior vena cava (SVC) and inferior vena cava (IVC) in the swine. Papillary muscle avulsion in three sheep caused significant tricuspid regurgitation with massive reflux into the right atrium (RA) and partial reflux into the SVC and IVC. TVCS placement eliminated reflux into the SVC and IVC. After fluid overload, there was enlargement of the right ventricle and RA and significant increase in right ventricle, RA, SVC, and IVC pressures, but no reflux into the IVC and SVC.


CONCLUSIONS
The results of this feasibility study justify detailed evaluation of TVCS insertion for functional chronic replacement of incompetent TV.
Clinic of Cardiology, Institute for Clinical and Experimental Medicine, Vídeňská 1958/9, 140 21, Prague 4, Czech Republic. jan.sochman@medicon.cz
Jan
J
Sochman
Jan H
JH
Peregrin
Dusan
D
Pavcnik
Barry T
BT
Uchida
Hans A
HA
Timmermans
Masashi
M
Shimohira
Young Ho
YH
Choi
Frederick S
FS
Keller
Josef
J
Rösch
D000818:Animals; D005240:Feasibility Studies; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000295:instrumentation*; D011474:Prosthesis Design; D012756:Sheep; D015607:Stents; D013552:Swine; D014261:Tricuspid Valve / Q000601:surgery*