Mechanical Aortic Valve Prostheses Offer a Survival Benefit Over Bioprostheses Among 50 to 65-Year-Olds: The AUTHEARTVISIT Study

Background: The present study investigated long-term mortality after aortic valve replacement (AVR) with bioprosthetic (B) or mechanical aortic valve prostheses (M) in a European social welfare state.  Methods: We analysed patient data from health insurance records covering 98% of the Austrian population between 2010 and 2018. Subsequent patient-level record linkage with national health data provided patient characteristics and clinical outcomes. Further reoperation, myocardial infarction, heart failure, and stroke were evaluated as secondary outcomes.  Findings: A total of 13 993 patients were analysed and the following age groups were examined separately: 65 years (10 654 patients: 1·26% M, 98·74% B). Multivariable Cox regression revealed that the use of B-AVR was significantly associated with higher mortality in patients aged 50 – 65 years compared to M-AVR (HR = 1·676 [1·289 – 2·181], p < 0·001). B-AVR also performed worse in a competing risk analysis regarding reoperation (HR = 3·483 [1·445 – 8·396], p = 0·005) and myocardial infarction (HR = 2·868 [1·255 – 6·555], p = 0·012). However, the risk of developing heart failure and stroke did not differ significantly after B-AVR and M-AVR in any age group. Interpretation: Patients aged 50 – 65 years who undergo M-AVR had better long-term survival, and a lower risk of reoperation and myocardial infarction, compared to B-AVR. Even though anticoagulation is crucial in patients with M-AVR, we did not observe significantly increased stroke rates in patients with M-AVR. This evident survival benefit in recipients of mechanical aortic valve prostheses aged < 65 years critically questions current guideline recommendations.  Clinical Trial Registration Details: The trial was registered at clinicaltrials.gov (NCT: NCT04900909). Funding Information: This work was supported by the institutional research laboratories ARGE Ankersmit (FOLAB Chirurgie). Declaration of Interests: All other authors report no competing interests. Ethics Approval Statement: This study was a nationwide, population-based cohort study and complied with the Declaration of Helsinki. It was approved by the ethics committee of lower Austria (EC number: GS1-EK-4/722-2021).