# The Potential Renal Protective Effect of Transcatheter Aortic Valve Replacement

## TL;DR

This study found that TAVR improves kidney function shortly after treatment, but long-term decline is similar in patients with and without chronic kidney disease.

## Contribution

The study demonstrates a potential renoprotective effect of TAVR, independent of pre-existing chronic kidney disease.

## Key findings

- Both CKD and non-CKD patients showed improved eGFR one month after TAVR.
- eGFR decline by three years was similar between CKD and non-CKD groups.
- CKD was the strongest predictor of mortality in TAVR patients.

## Abstract

Background

The incidence of aortic stenosis (AS) is steadily increasing, posing a significant healthcare burden. Transcatheter aortic valve replacement (TAVR) is being used more frequently to treat patients with symptomatic AS. This study evaluated long-term changes in renal function and mortality in TAVR patients over a period of up to three years, including those with normal creatinine (Cr) levels and those with chronic kidney disease (CKD).

Methods

We conducted a retrospective review of 270 patients who underwent TAVR between 2012 and 2017 at a rural tertiary referral center. Collected data included baseline serum Cr and estimated glomerular filtration rate (eGFR), with follow-up measurements taken at 30 days, six months, one year, two years, and three years post-TAVR. Patients were categorized into two groups: those with CKD and those without.

Results

Both groups showed similar improvements in eGFR at one month (6.3 mL/min/m², p < 0.001). However, by three months, eGFR levels returned to their pre-TAVR baseline. At the three-year mark, an average decline of 5.3 mL/min/m² was observed in both groups (p < 0.001). Despite CKD patients having worse kidney function throughout the study period, the extent of eGFR reduction was similar between the CKD and non-CKD groups, indicating that eGFR decline was independent of CKD status. Mortality rates were higher in CKD patients (56.9 (39%) vs. 24.6 (22%); p = 0.006). Multivariate analysis identified CKD as the most reliable predictor of mortality.

Conclusions

Renal function significantly improved at one month post-TAVR in both CKD and non-CKD patients. Although eGFR initially improved after TAVR, the subsequent decline was similar in both groups, suggesting that the reduction in eGFR is independent of CKD status. Cardiorenal syndrome, which can occur with AS, may improve with TAVR. These findings support the potential renoprotective effect of TAVR in patients with CKD.