Determining which prosthetic to use during aortic valve replacement in patients aged younger than 70 years: A systematic review of the literature

Background: The choice of bioprosthesis versus mechanical prosthesis in patients aged less than 70 years undergoing aortic valve replacement (AVR) remains controversial, with guidelines disparate in their recommendations. The objective of this study was to explore outcomes after AVR for various age ranges based on type of prosthesis. Methods: A systematic review was undertaken according to the Preferred Reporting Instructions for Systematic Reviews and Meta-Analyses (PRISMA) guidelines by using Medline (PubMed), Cochrane, Web of Science, Embase, and Scopus databases. Rates of long-term survival (primary outcome), reoperation, major bleeding, thromboembolism, stroke, structural valve deterioration, and endocarditis were compared between subjects receiving biologic and mechanical prostheses. Findings were grouped into patients aged <60 years, aged ≤65 years, and finally aged <70 years. Results: A total of 19 studies met inclusion criteria. Seven evaluated patients aged <60 years, 4 of which found mechanical prosthesis patients to have higher long-term survival, whereas the remaining studies found no difference. Eight additional studies included patients aged 65 years or younger, and 9 studies included patients aged <70 years. The former found no difference in survival between prosthesis groups, whereas the latter favored mechanical prostheses in 3 studies. Bleeding, thromboembolism, and stroke were more prevalent in patients with a mechanical prosthesis, whereas reoperation was more common in those receiving a bioprosthesis. Conclusions: Published literature does not preclude the use of bioprostheses for AVR in younger patients. As new valves are developed, the use of bioprosthetic aortic valves in younger patients will likely continue to expand. Clinical trials are needed to provide surgeons with more accurate guidelines.