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Updated: Jan 27, 2026

Full-root Aortic Valve Replacement by Stentless Aortic Xenografts in Patients with Small Aortic Roots
Published on: May 21, 2017
Tissue versus mechanical aortic valve replacement in younger patients: A multicenter analysis
Alexander Iribarne1, Bruce J Leavitt2, Michael P Robich3
1Section of Cardiac Surgery, Department of Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH.
Objective:
The goal of this study was to examine the long-term survival of patients between the ages of 50 and 65 years who underwent tissue versus mechanical aortic valve replacement (AVR) in a multicenter cohort.
Methods:
A multicenter, retrospective analysis of all AVR patients (n = 9388) from 1991 to 2015 among 7 medical centers reporting to a prospectively maintained clinical registry was conducted. Inclusion criteria were: patients aged 50 to 65 years who underwent isolated AVR. Baseline comorbidities were balanced using inverse probability weighting for a study cohort of 1449 AVRs: 840 tissue and 609 mechanical. The primary end point of the analysis was all-cause mortality. Secondary end points included in-hospital morbidity, 30-day mortality, length of stay, and risk of reoperation.
Results:
During the study period, there was a significant shift from mechanical to tissue valves (P < .001). There was no significant difference in major in-hospital morbidity, mortality, or length of hospitalization. Also, there was no significant difference in adjusted 15-year survival between mechanical versus tissue valves (hazard ratio, 0.87; 95% confidence interval [CI], 0.67-1.13; P = .29), although tissue valves were associated with a higher risk of reoperation with a cumulative incidence of 19.1% (95% CI, 14.4%-24.3%) versus 3.0% (95% CI, 1.7%-4.9%) for mechanical valves. The reoperative 30-day mortality rate was 2.4% (n = 2) for the series.
Conclusions:
Among patients 50 to 65 years old who underwent AVR, there was no difference in adjusted long-term survival according to prosthesis type, but tissue valves were associated with a higher risk of reoperation.
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