Data collection

An electronic case report form was used to collect data, which was entered by a dedicated study nurse. Patient demographics, echocardiographic parameters and medical history were recorded at baseline, alongside AS-attributed symptoms (chest pain, shortness of breath and dizziness on exertion/syncope). Surgical risk was calculated using logistic EuroSCORE I and EuroSCORE II risk-stratification tools, with frailty determined by the inability to walk 5 m in ≤6 s and/or to perform activities of daily living.¹⁶ Stroke volume and flow rate were not calculated. The decision on which treatment approach to take (TAVI, SAVR, balloon aortic valvuloplasty (BAV), watchful waiting or active decision not-to-treat) and the time between assignment to AVR and its performance were then documented. All data were subject to automatic checks for plausibility and completeness.