title: The disc rotation in patients operated upon with the Björk-Shiley tilting disc valves with radiopaque markers.
mesh_terms: D001021:Aortic Valve; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000601:surgery; D006350:Heart Valve Prosthesis; D006801:Humans; D008297:Male; D008722:Methods; D008875:Middle Aged; D008943:Mitral Valve; D013902:Radiography, Thoracic