Renal function changes associated with transcatheter aortic valve-in-valve for prosthetic regurgitation compared to stenosis

Background: Renal dysfunction is frequently encountered in patients with aortic prosthesis degeneration requiring valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR). The effect of VIV TAVR on renal function in patients with bioprosthetic aortic regurgitation (AR) and stenosis (AS) is unknown. Objectives: The aims of this study were to describe the change in renal function after VIV TAVR and to compare differences in renal function changes in those with predominant prosthetic regurgitation compared to stenosis. Methods: All VIV TAVR between June of 2014, and October 2019 (n = 141) at a single institution were reviewed. Baseline renal function parameters including estimated glomerular filtration rate (eGFR) were compared with post-discharge follow-up values in both prosthetic AR and AS patient groups. Linear regression analysis was performed to determine correlates of renal function change. Results: Mean baseline eGFR was lower in the AR group (55 SD21 vs. 64 SD24 ml/min/1.73 m² p = 0.0495). At post-discharge follow-up there was an increase in mean eGFR in the AR group which was not present in the AS group (8 SD12 vs. 0 SD11 ml/min/1.73 m² respectively p = 0.0006). There were strong correlations between change in creatinine (β = −0.57, R² = 0.64, p < 0.0001) and BUN (β = −0.61, R² = 0.51, p < 0.0001), and pre-procedure values in the AR group. Conclusions: Patients who underwent VIV TAVR for AR experienced significant improvement of renal function at post-discharge follow-up. More advanced renal dysfunction at baseline was associated with greater improvement in renal function at post discharge in AR patients.