Long-term clinical outcomes in patients between the age of 50-70 years receiving biological versus mechanical aortic valve prostheses

OBJECTIVES
The last 2 decades have seen an incremental use of biological over mechanical prostheses. However, while short-term clinical outcomes are largely equivalent, there is still controversy about long-term outcomes.

METHODS
All patients between the ages of 50 and 70 years undergoing elective/urgent isolated aortic valve replacement at our institute between 1996 and 2023 were included. Trends, early, and long-term outcomes were investigated.

RESULTS
A total of 1708 (61% male) patients with a median age of 63.60 (interquartile range: 58.28–67.0) years were included of which 1191 (69.7%) received a biological prosthesis. After inverse propensity score weighting, there were no short-term differences when comparing patients receiving biological and mechanical valves. However, patients who received mechanical prostheses had better long-term survival (P < 0.001). Sub-group analysis revealed that patients with biological size 19 mm prosthesis had the worst long-term survival. Patients with a size 21-mm mechanical prosthesis had better survival compared to both size 19-mm [hazard ratio (HR) 0.25, 95% confidence interval (CI) 0.17–0.37, P < 0.001], 21-mm (HR 0.33, 95% CI 0.23–0.48, P < 0.001) and 23-mm (HR 0.40, 95% CI 0.27–0.60, P < 0.001) biological prosthesis. Additionally, patients with severe patient–prosthesis mismatch exhibited the lowest survival rate compared to those with moderate or no (HR 1.56, 95% CI 1.21–2.00, P < 0.001).

CONCLUSIONS
Patients aged between 50 and 70 years with a mechanical aortic prosthesis had better long-term survival compared to those with a biological prosthesis. Our study underscores the need for a critical re-evaluation of prosthesis selection strategies in this age group.