The Annals of Thoracic Surgery, Vol 37, 398-403, Copyright © 1984 by The Society of Thoracic Surgeons
Early results of valve replacement with the Bjork-Shiley convexoconcave prosthesis
WG Marshall Jr, NT Kouchoukos, SB Pollock and EL Bradley
The Bjork-Shiley convexoconcave prosthetic valve has design characteristics
that may result in a lower incidence of thromboembolic complications than
the conventional spherical Bjork-Shiley prosthesis. We evaluated the
results of valve replacement with the convexoconcave prosthesis in 248
patients receiving 301 prosthetic valves between March, 1979, and June,
1981. One hundred thirteen patients had aortic valve replacement (AVR), 73
had mitral valve replacement (MVR), and 62 had multiple valve replacement.
Two hundred nine (84%) were in New York Heart Association Class III or IV.
The median duration of follow-up was 13 months, and follow-up information
was available for 246 (99%) of the patients. The actuarial incidence of
freedom from thromboembolism at two years was 98% in the AVR group, 97% in
the MVR group, and 87% in the group having multiple valve replacement.
There were no documented episodes of valve thrombosis or mechanical failure
and no fatal thromboembolic complications. The absence of valve thrombosis
is in marked contrast to the results reported with the spherical disc
valve. Although longer follow-up is necessary, it appears that the
convexoconcave design represents a major improvement in the Bjork- Shiley
prosthesis.