Variablity of Mechanical or Tissue Valve Implantation in Patients Undergoing Surgical Aortic Valve Replacement in Spain: National Retrospective Analysis from 2007 to 2018.

There is no robust evidence regarding the types of valves implanted among patients undergoing surgical aortic valve replacement (SAVR) in Spain. All cases of patients undergoing SAVR ± coronary artery bypass grafting from January 2007 to December 2018 in the public Spanish National Health System were included. We analyzed the trends of SAVR volume, risk profile and type of implanted valve across time and place. Using multivariable logistic regression, we identified factors associated with biological SAVR. In total, 62,870 episodes of SAVR in 15 Spanish territories were included. In 35,693 (56.8%), a tissue valve was implanted. The annual volume of procedures increased from 107.3/million (2007) to 128.6 (2017). In 2018, it fell to 108.5. Age increased and Charlson's comorbity index worsened throughout the study period. Tissue valve implantation increased in most regions. After adjusting for other covariates, we observed a high variability in aortic valve implantation across different regions, with differences of as much as 20-fold in the use of tissue valves. Between 2007 and 2018, we detected a significant increase in the use of bioprostheses in patients undergoing SAVR in Spain, and a great variability in the types of valve between the Spanish territories, which was not explained by the different risk profiles of patients