The Annals of Thoracic Surgery, Vol 46, 331-336, Copyright © 1988 by The Society of Thoracic Surgeons
In vitro analysis of performance of porcine xenografts with inward bending of stent posts: real-time measurement of valve orifice area using an area meter
K Akiyama, O Sawatani, E Imamura, H Koyanagi, M Higashidate and K Tamiya
Department of Cardiovascular Surgery, Heart Institute of Japan, Tokyo Women's Medical College.
The influence of inward bending of the stent posts on bioprosthetic valve
function was assessed in a hydromechanical simulation of the left heart. A
Carpentier-Edwards mitral xenograft (31 mm) and an aortic xenograft (27 mm)
were used. Valve function was evaluated before and after the stent posts
were bent inward 15 degrees by suture constriction of the tops of the three
posts. To evaluate the effects of the stent-post deformity on valve
performance, the mean transvalvular pressure drop during steady flow, the
bioprosthetic valve orifice area, and the maximum valve opening and closing
speeds during pulsatile flow were measured using an area meter. Steady-flow
data showed identical transvalvular pressure drops, and no significant
difference in valve performance was detected in the pulsatile-flow study
under the two experimental conditions (i.e., normal valve and deformed
valve). We conclude that a 15-degree inward bending of the stent posts does
not appreciably affect valve function in vitro.
