부산대학교 도서관

Introduction: Transcatheter aortic valve replacement (TAVR), previously reserved for intermediate to prohibitive surgical risk, has now expanded to patients with severe aortic stenosis of any surgical risk. However, bioprostheses are prone to structural valve degeneration (SVD), a progressive process that limits valve durability. As the population undergoing TAVR shifts toward a lower-risk and younger profile, long-term durability is a crucial determinant for patient outcomes. Our objective was to report the characteristics of and assess risk factors for SVD in a veteran TAVR population.Methods: Patients undergoing TAVR at our Veterans Affairs Medical Center were retrospectively evaluated for SVD and other endpoints using recently standardized consensus criteria. Multivariate Cox proportional hazards analysis was performed to evaluate risk factors for SVD.Results: From 2013 to 2020, 312 patients (median age 79.0) underwent TAVR. Survival from all-cause mortality was 90.8% at 1 year, 76.1% at 3 years, and 64.0% at 5 years (Figure 1). Cumulative freedom from SVD was 98.0% at 1 year, 95.7% at 3 years, and 91.8% at 5 years. The 13 patients who met criteria for SVD were classified as moderate hemodynamic, and 2 required intervention. Median time to SVD was 1.04 years. Independent predictors of SVD include age (HR=0.92, CI:0.86-0.99) and valve size (HR=0.16, CI:0.03-0.81).Conclusions: SVD was evident at a low but detectable rate in 5 year follow-up, and associated with risk factors of patient age and implanted valve size. Further understanding of TAVR biomechanics will be essential to inform patient-specific risk of SVD. Figure 1: Kaplan-Meier curves of survival and freedom from SVD