Mitral Valve Replacement with Preservation of the Subvalvular Structures Where Possible: an Echocardiographic and Clinical Comparison with Cases Where Preservation Was Not Possible - Straub, U; Feindt, P; Huwer, H; Kalweit, G; Volkmer, I; Gams, E (The Thoracic and Cardiovascular Surgeon, 1994)