|
|
||||||||
The Journal of Thoracic and Cardiovascular Surgery, Vol 73, 563-569, Copyright © 1977 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
VO Bjork, A Henze and T Hindmarsh
This paper describes a new, noninvasive method for evaluating the in vivo
function of the Bjork-Shiley tilting disc valve in the aortic, mitral, and
tricuspid positions. The tilting disc was equipped with a ring-shaped
radiopaque marker, which permits visualization of the motion of the disc by
both cineradiographic and fluoroscopic studies. A beam direction
corresponding to the axis of motion of the disc should be sought for
calculation of the prosthetic opening angle, whereas prostehtic valve
closure is demonstrated by a beam direction deviating 20 to 30 degrees from
the valve ring plane. Complete opening to 60 degrees and closure of the
prosthetic valve, indicating free motility of the tilting disc, were
confirmed by cineradiograms. The error of estimation of the in vivo opening
angle is small with deviations of less than 15 degrees from the ideal beam
direction and negligible for opening angles approaching 60 degrees.
Deviations in two planes simultaneously cause less error than deviation in
one plane. The radiopaque marker was designed to detect mechanical valve
failure owing to thrombotic obstruction. The incidence of this particular
complication was 8.1 per 100 patient-years after aortic valve replacement
without anticoagulation treatment. With anticoagulation, this incidence was
zero after aortic and 2.5 after mitral valve replacement. In our clinical
experience to date, which comprises over 1,250 implants, we have not
encountered a single case of primary mechanical valve dysfunction. Our
current program includes a change- over to the radiopaque tilting-disc
model of the Bjork-Shiley prosthesis, which was introduced at this clinic
in March, 1975.
ARTICLES
Radiopaque marker in the tilting disc of the Bjork-Shiley heart valve. Evaluation of in vivo prosthetic valve function by cineradiography
This article has been cited by other articles:
![]() |
W. W. O'Neill, J. G. Chandler, R. E. Gordon, D. M. Bakalyar, A. H. Abolfathi, M. D. Castellani, J. L. Hirsch, D. W. Wieting, J. S. Bassett, K. C. Beatty, et al. Radiographic Detection of Strut Separations in Bjork-Shiley Convexo-Concave Mitral Valves N. Engl. J. Med., August 17, 1995; 333(7): 414 - 420. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |