Bioprosthetic vs Mechanical Aortic Valve Replacement in Patients 40 to 75 Years of Age
Original Research
Central Illustration
Abstract
Background
The choice of bioprosthetic or mechanical surgical aortic valve replacement (AVR) should balance individual valve durability with the potential liabilities of oral anticoagulation.
Objectives
To inform clinical practice, this study sought to evaluate contemporary, real-world, long-term AVR outcomes from the Society of Thoracic Surgeons Adult Cardiac Surgery Database (STS ACSD).
Methods
All patients undergoing primary isolated bioprosthetic or mechanical AVR were identified. Patients aged <40 and >75 years with endocarditis, emergency/salvage status, shock, ejection fraction ≤25%, and any prior cardiac surgery were excluded. Validated methodology was applied for linkage to the National Death Index to define longitudinal all-cause mortality (2008-2019). Robust risk adjustment was performed by using age-specific inverse probability weighting and restricted cubic splines to model nonlinear age relationships. Sensitivity analyses excluded pure aortic insufficiency, intermediate/high risk (STS predicted risk of operative mortality >4%), and discontinued valve types.
Results
A total of 109,842 patients underwent bioprosthetic (n = 94,125) or mechanical (n = 15,717) AVR during the study period. After risk adjustment, freedom from all-cause mortality favored mechanical valves in patients aged 60 years and younger. Age group–specific analyses showed that mechanical valves were associated with lower all-cause mortality in all age groups ≤60 years. These results remained consistent across all sensitivity analyses.
Conclusions
In patients aged ≤60 years, mechanical AVR was associated with an independent risk-adjusted survival benefit compared with bioprosthetic AVR. These contemporary 12-year survival data further inform patient and provider shared clinical decision-making regarding prosthetic aortic valves.
References
1. "Mechanical or biologic prostheses for aortic-valve and mitral-valve replacement". N Engl J Med . 2017;377:1847-1857.
2. "Survival and long-term outcomes following bioprosthetic vs mechanical aortic valve replacement in patients aged 50 to 69 years". JAMA . 2014;312:1323-1329.
3. "Survival following surgical aortic valve replacement in low-risk patients: a contemporary trial benchmark". Ann Thorac Surg . 2023;117:106-112.
4. "National trends in TAVR and SAVR for patients with severe isolated aortic stenosis". J Am Coll Cardiol . 2022;80:2054-2056.
5. "Transcatheter aortic-valve replacement in low-risk patients at five years". N Engl J Med . 2023. 3891949-3891960.
6. "Mechanical versus biologic prostheses for surgical aortic valve replacement in patients aged 50 to 70". Ann Thorac Surg . 2020;110:102-110.
7. "Mechanical or biological prosthesis for aortic valve replacement in patients aged 45 to 74 years". J Thorac Cardiovasc Surg . Published online July2, 2024. https://doi.org/10.1016/j.jtcvs.2024.06.029.
8. "Aortic valve replacement with mechanical valves vs perimount bioprostheses in 50- to 69-year-old patients". JACC Adv . 2023;2:100359.
9. "Aortic valve replacement with mechanical vs. biological prostheses in patients aged 50-69 years". Eur Heart J . 2016;37:2658-2667.
10. "Guidelines vs practice: surgical versus transcatheter aortic valve replacement in adults ≤60 years". Ann Thorac Surg . Published online August22, 2024. https://doi.org/10.1016/j.athoracsur.2024.07.036.
11. "Transcatheter versus surgical aortic valve replacement in patients younger than 65 years in the US". J Thorac Cardiovasc Surg . Published online January9, 2025. https://doi.org/10.1016/j.jtcvs.2024.12.025.
12. "Current penetration, completeness, and representativeness of the Society of Thoracic Surgeons Adult Cardiac Surgery Database". Ann Thorac Surg . 2022;113:1461-1468.
13. "Validation of US CDC National Death Index mortality data, focusing on differences in race and ethnicity". BMJ Health Care Inform . 2023;30:e100737.
14. "Multiarterial vs single-arterial coronary surgery: 10-year follow-up of 1 million patients". Ann Thorac Surg . 2024;117:780-788.
15. "Balance diagnostics for comparing the distribution of baseline covariates between treatment groups in propensity-score matched samples". Stat Med . 2009;28:3083-3107.
16. "Variance estimation when using inverse probability of treatment weighting (IPTW) with survival analysis". Stat Med . 2016;35:5642-5655.
17. "Moving towards best practice when using inverse probability of treatment weighting (IPTW) using the propensity score to estimate causal treatment effects in observational studies". Stat Med . 2015;34:3661-3679.
18. "2020 ACC/AHA guideline for the management of patients with valvular heart disease: executive summary: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines". J Am Coll Cardiol . 2021;77:4: 450-500.
19. "The Society of Thoracic Surgeons Coronary Artery Bypass Graft Composite Measure: 2021 methodology update". Ann Thorac Surg . 2022;113:1954-1961.