Temporal changes in biomarker levels and their association with the early degeneration stage of transcatheter aortic valves in 18F-fluorodeoxyglucose and 18F-sodium fluoride positron emission tomography studies.

Abstract

Introduction: As transcatheter aortic valve implantation (TAVI) indications expand, understanding the valve degeneration process and potential influencing biomarkers becomes increasingly important.

Aim: To investigate temporal changes in biomarker levels and their potential association with ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) and ¹⁸F-sodium fluoride (¹⁸F-NaF) uptake, assessed using positron emission tomography/computed tomography (PET/CT) studies as markers for native aortic annulus calcifications and early-stage TAVI valve degeneration.

Material and methods: A total of 71 TAVI patients underwent blood sampling and transthoracic echocardiography at baseline (pre-TAVI) and 6, 12, 18, and 24 months after the procedure. PET/CT using ¹⁸F-NaF and ¹⁸F-FDG was performed at 6 and 24 months. Serum levels of matrix metalloproteinase-3 (MMP-3), matrix metalloproteinase-9 (MMP-9), and osteopontin (OPN) were measured. In addition, plasma levels of osteoprotegerin (OPG), lipoprotein a (Lp(a)), and oxidized LDL (ox-LDL) were assessed.

Results: Finally, 31 patients (median age: 84.0 years) completed the study. Valve function improved after TAVI and remained stable during follow-up. Over 24 months, OPN levels decreased (p = 0.010), while MMP-3 and MMP-9 levels increased (p = 0.046 and p = 0.041). MMP-3 and MMP-9 showed multiple positive correlations across time points. OPN, ox-LDL, and OPG demonstrated significant negative correlations with follow-up effective orifice area index and effective orifice area (EOA). No significant correlations were found between biomarkers and PET/CT uptake.

Conclusions: Significant biomarker changes over 24 months and negative correlations with EOA suggest potential roles in aortic valve function. However, no correlations between biomarkers and PET/CT results were observed.