Aortic Valve Stenosis/therapy; Aortic Valve; Cardiac Catheterization/methods; Heart Valve Prosthesis Implantation/methods; Acute Kidney Injury/etiology; Acute Kidney Injury/mortality; Aged; Aged, 80 and over; Aortic Valve/physiopathology; Aortic Valve Stenosis/diagnosis; Aortic Valve Stenosis/mortality; Aortic Valve Stenosis/physiopathology; Cardiac Catheterization/adverse effects; Cardiac Catheterization/mortality; Chi-Square Distribution; Female; Germany; Heart Valve Prosthesis Implantation/adverse effects; Hospital Mortality; Humans; Intensive Care Units; Kaplan-Meier Estimate; Length of Stay; Logistic Models; Male; Odds Ratio; Patient Selection; Retrospective Studies; Risk Assessment; Risk Factors; Stroke/etiology; Stroke/mortality; Time Factors; Treatment Outcome