Calcinosis/therapy; Cardiac Catheterization; Heart Valve Prosthesis Implantation; Mitral Valve Annuloplasty; Mitral Valve Insufficiency/therapy; Mitral Valve Stenosis/therapy; Mitral Valve/surgery; Aged; Aged, 80 and over; Calcinosis/diagnostic imaging; Calcinosis/physiopathology; Cardiac Catheterization/adverse effects; Cardiac Catheterization/mortality; Clinical Decision-Making; Databases, Factual; Decision Support Techniques; Female; Heart Valve Prosthesis Implantation/adverse effects; Heart Valve Prosthesis Implantation/mortality; Hemodynamics; Humans; Male; Middle Aged; Mitral Valve/diagnostic imaging; Mitral Valve/physiopathology; Mitral Valve Annuloplasty/adverse effects; Mitral Valve Annuloplasty/mortality; Mitral Valve Insufficiency/diagnostic imaging; Mitral Valve Insufficiency/physiopathology; Mitral Valve Stenosis/diagnostic imaging; Mitral Valve Stenosis/physiopathology; Risk Factors; Severity of Illness Index; Treatment Outcome