TAVR Could Improve Kidney Function, Predict Mortality in CKD Patients with Aortic Stenosis

Undergoing transcatheter aortic valve replacement (TAVR) could lead to improvements in kidney function among patients with chronic kidney disease (CKD), according to the results of a new study.

An analysis of more than 800 patients treated at the Rabin Medical Center in Israel, results indicate more than 80% of patients undergoing TAVR showed stable or improved kidney function 1-month post-procedure and also suggest changes in kidney function following TAVR can help identify patients at increased risk of mortality.

“Improvement in kidney function had a favorable association with 2-year mortality, whereas deterioration in kidney function was associated with increased mortality regardless of baseline CKD status. Future studies should focus on identifying the role of cardiorenal syndrome as a main cause of CKD in the aortic stenosis population in order to improve patient selection and optimize outcomes after TAVR,” wrote investigators.

With TAVR populations exhibiting an increased prevalence of CKD and CKD having an association with increased mortality among TAVR patients, clinicians from the Rabin Medical Center designed the current study to further explore the relationship between CKD and TAVR. Specifically, investigators created the study with the intent of assessing change in kidney function at 1 month and the association of TAVR with midterm mortality.

Using their own site, the single-center, retrospective study included consecutive patients who underwent TAVR from November 5, 2008-December 31, 2019. In total, investigators identified 1038 patients for inclusion in their study. Of these, 894 had data related to eGFR and serum creatinine levels and were included in the final analyses. This 894-patient group had a mean age of 82.2 (SD, 7.1) years, 51.2% were women, and 40.5% were treated from 2017-2019. The mean STS score among the study cohort was 5.2% (SD, 4.0) and the mean eGFR was 65.1 (SD, 23.1) mL/min/1.73 m2.

Investigators found evidence of acute kidney injury in 11.1% of patients at 48 hours. Of these, 63.5% were resolved by discharge. Analysis of outcomes at 1 month after TAVR suggested eGFR improved by 10% or more in 36.8% of patients and deteriorated by 10% or more in 26.1% of patients. Overall, CKD stage remained stable or improved in 80.6% of patients and just 0.97% of patients progressed to stage 5 CKD at 1 month.

Upon analysis, investigators found deterioration of 10% or more in eGFR at 1 month after TAVR was associated with a 2-fold increase in risk of mortality at 2 years (HR, 2.16; 95% CI, 1.24-5.24; P=.04). When assessing patients who experienced an eGFR improvement to 60 mL/min/1.73m2 or more after TAVR, investigators found these patients achieved similar mortality to those with a baseline eGFR greater than 60 mL/min/1.73m2.

Results also indicated lower STS scores, greater left ventricular ejection fraction, greater baseline eGFR, lack of acute kidney injury at discharge from TAVR, and lower contrast-eGFR ratio were associated with steady-state CKD status resolution following TAVR.

In an invited commentary, Benjamin Galper, MD, of the Mid-Atlantic Permanente Medical Group, commended investigators of the current study for their contributions to the growing understanding of TAVR and cardiorenal syndrome but cautioned clinicians to consider current limitations when interpreting results of the study.

“Witberg et al add to the growing body of data that TAVR not only arrests the cycle of cardiorenal syndrome but also may lead to improvement in kidney function in patients with CKD. However, our ability to discriminate cardiorenal syndrome from other etiologies of CKD in patients with AS is limited,” wrote Galper.

This study, “Change in Kidney Function and 2-Year Mortality After Transcatheter Aortic Valve Replacement,” was published inn JAMA Network Open.