Serum biomarkers in structural deterioration of surgical bioprosthetic aortic valves: A systematic review and meta-analysis

BACKGROUND Patients with surgically implanted bioprosthetic aortic valves remain at risk of structural valve deterioration (SVD), a progressive process that may compromise durability and clinical outcomes. In this study, we aimed to assess serum biomarkers in patients with versus without SVD following surgical aortic valve replacement (SAVR). METHODS PubMed, Scopus, and Web of Science were systematically searched from inception through September 9, 2026 for studies comparing serum biomarkers in patients with versus without SVD following SAVR with a bioprosthetic aortic valve. Random-effects models were used to calculate pooled mean differences (MDs) with 95% confidence intervals (CIs). PROSPERO registration: CRD420250655746. RESULTS Four studies with 819 patients (193 [23.6%] with SVD) were included. Patients with SVD had higher serum levels of low-density lipoprotein (LDL) (MD 0.23 mmol/L; 95% CI 0.05-0.41; p<0.01) compared to patients without SVD. Additionally, oxidized LDL levels (MD 3.86 U/L; 95% CI 1.14-6.58; p<0.01) as well as the concentration of small dense LDL-C (MD 0.14 mmol/L; 95% CI 0.03-0.25; p<0.01) were higher among patients with SVD. Furthermore, ApoB/ApoA-1 ratio was higher among SVD patients (MD 0.07; 95% CI 0.03-0.11; p<0.01) compared to patients without SVD. However, there were no significant differences between the groups in levels of triglycerides, high-density lipoprotein (HDL), creatinine, and fasting glucose. CONCLUSIONS In patients with surgically implanted bioprosthetic aortic valves, higher serum LDL, oxidized LDL, small dense LDL-C, and ApoB/ApoA-I ratio were associated with SVD. Given the small observational evidence base, these findings are hypothesis-generating and require validation before these biomarkers can be used for prediction or clinical decision-making.