[Structural valve deterioration after transcatheter aortic valve replacement: a research update]

Abstract

Structural valve deterioration (SVD) refers to intrinsic and irreversible pathological changes in the components of prosthetic heart valves, manifesting as fibrosis, calcification, wear and tear, loosening, as well as strut fracture or deformation of the valve framework. These changes ultimately lead to valve stenosis and/or regurgitation.The mechanisms may be related to mechanical stress, immune response and abnormal calcium-phosphorus metabolism. Studies have shown that risk factors for SVD include patient factors (such as age, underlying cardiovascular disease and comorbidities), valve factors (such as material properties, processing techniques, and valve type), and surgical factors (such as valve injury, suboptimal stent expansion, and irregular stent release morphology). Clinical imaging assessment of SVD demonstrates complementary advantages among echocardiography, multi-detector spiral CT and cardiac magnetic resonance imaging, with distinct diagnostic objectives. The primary management strategies for SVD after trans-catheter aortic valve replacement (TAVR) include drug therapy, redo-TAVR, surgical aortic valve replacement (SAVR) and the novel SURPLUS technique. Among them, redo-TAVR has become a common method because of its minimally invasive nature, but it is still necessary to further clarify the patient indications and optimize the surgical strategy. SAVR is reserved for young, low-risk patients; SURPLUS combines the advantages of SAVR and TAVR, making it suitable for cases where redo-TAVR is unfeasible or contraindicated, while the risk of SAVR is excessively high. This article reviews the latest progress of SVD following TAVR treatment to provide reference for research into the durability of bioprosthetic valve and clinical intervention of SVD.

Keywords: Aortic valve; Bioprosthetic valve; Review; Structural valve deterioration; Transcatheter aortic valve replacement.

图1. 生物瓣功能障碍类型及其发展为生物瓣衰败示意图