Aortic Valve Stenosis/therapy; Balloon Valvuloplasty; Heart-Assist Devices; Percutaneous Coronary Intervention; Ventricular Dysfunction, Left/therapy; Ventricular Function, Left; Aged; Aged, 80 and over; Aortic Valve Stenosis/complications; Aortic Valve Stenosis/diagnosis; Aortic Valve Stenosis/mortality; Aortic Valve Stenosis/physiopathology; Balloon Valvuloplasty/adverse effects; Balloon Valvuloplasty/mortality; Chi-Square Distribution; Echocardiography, Doppler, Color; Feasibility Studies; Female; Heart Arrest/etiology; Heart Arrest/therapy; Hemodynamics; Hospital Mortality; Humans; Male; Percutaneous Coronary Intervention/adverse effects; Percutaneous Coronary Intervention/mortality; Prosthesis Design; Retrospective Studies; Severity of Illness Index; Time Factors; Treatment Outcome; Ventricular Dysfunction, Left/complications; Ventricular Dysfunction, Left/diagnosis; Ventricular Dysfunction, Left/mortality; Ventricular Pressure