Outcomes of tissue versus mechanical aortic valve replacement in patients 50 to 70 years of age.

Background: Societal guidelines suggest that aortic valve replacement (AVR) in patients age 50 to 70 years can be performed with either bioprosthetic or mechanical valves. This study reviewed outcomes between these valve types among patients aged 50 to 70 years undergoing AVR.

Methods: We examined adult patients 50 to 70 years undergoing isolated AVR with a mechanical or bioprosthetic valve at a single institution between 2010 and 2018. Kaplan-Meier analysis was used to evaluate longitudinal survival and multivariable Cox regression analysis was used for risk adjustment. A propensity-matched analysis was performed as well.

Results: A total of 723 patients underwent isolated AVR with 467 (64.6%) receiving a bioprosthetic valve. At baseline, patients undergoing bioprosthetic AVR were older (median 65 vs 60 years; P < .001). One-year survival was comparable, however, survival at 5 years was significantly higher among patients undergoing mechanical AVR (95.5% vs 82.6%; P = .010). Among the 196 matched pairs, bioprosthetic AVR was associated with an increased adjusted hazard for death (hazards ratio, 3.29; P < .001). Additionally, 5-year freedom from stroke and bleeding were similar following matching, though mechanical AVR was associated with a greater freedom from repeat valve intervention (97.5% vs 92.9%; P = .020).

Conclusion: In patients age 50 to 70, mechanical AVR is associated with improved long-term survival and freedom from repeat aortic valve intervention. Further large cohort studies should be performed to explore the potential benefits of mechanical valve replacement in this age range.