Other variables
We collected basal and demographical variables for each patient by
direct interview or reviewing medical records. The Charlson index was
used to assess comorbidities (23). Clinical and surgical-related
variables were also collected.
Operative risk was calculated using the European System for Cardiac
Operative Risk Evaluation (EuroSCORE) I and II (24,25). Health-related
quality of life (HRQoL) was assessed using the EuroQOL 5D5L
questionnaire (26).