title: Retrograde catheterization of left ventricle through tilting disc valves using a modified catheter system.
mesh_terms: D001021:Aortic Valve / Q000601:surgery; D006328:Cardiac Catheterization / Q000379:methods*; D006339:Heart Rate; D006350:Heart Valve Prosthesis; D006801:Humans; D008943:Mitral Valve / Q000601:surgery