Prosthetic Cardiac Valves:
Bjork-Shiley: This valve has a band-like radiopaque ring and contains a tilting disc. When seen in profile, the disc should open to an angle of 60-70 degrees. An opening of less than 55 degrees should be considered suspicious for thrombosis.Carpentier-Edwards: This is a porcine valve. The large wire struts point in the direction of flow.
Medtronic Hall: The valve contains a characteristic "S" shaped central band.
St. Jude: This valve appears as a thin line on chest radiographs and may be very difficult to see because the base ring is radiolucent. Newer models have a radiopaque ring which is much easier to identify.