Albuminuria linked to worse TAVR outcomes, including a higher risk of death
Transcatheter aortic valve replacement (TAVR) patients presenting with albuminuria face a greater risk of death or a hospital readmission due to heart failure, according to new findings published in the American Journal of Cardiology.[1]
“Because patients with aortic stenosis are old and commonly have chronic kidney disease (CKD), it is essential to evaluate the renal function before TAVR,” wrote first author Akihiro Tobe, MD, a cardiologist with Nagoya University Graduate School of Medicine in Japan, and colleagues. “Albuminuria indicates glomerular injury and is an important factor in the assessment of renal function or diagnosis of CKD. Albuminuria as well as the reduction of estimated glomerular filtration rate (eGFR) are risk factors for poor prognosis in patients with cardiovascular diseases. However, compared with eGFR, the assessment of albuminuria is sometimes neglected in clinical practice.”
Tobe et al. tracked data from 228 TAVR patients with severe aortic stenosis (AS) who were treated at a single facility from April 2018 to December 2021. Urine data was available for each patient, and patients were excluded in cases of in-hospital mortality due to procedural complications.
Patients were separated into two groups based on their albumin-to-creatinine ratio (ACR). While 117 patients had a high ACR, the other 111 patients had a low ACR. There were no differences between these two groups when it came to age, sex or body mass index. Patients with a high ACR were more likely to have a history of diabetes or prior percutaneous coronary intervention. A high ACR was also linked to a lower eGFR.
The study’s primary outcome was the composite of all-cause death and readmission due to heart failure. After a median follow-up period of 467 days, this outcome was seen in 22 patients with a high ACR and five patients with a low ACR.
“Patients with a high ACR were at a significantly higher risk of all-cause death, cardiac death and heart failure readmission,” the authors wrote. “However, the incidence of noncardiac death was not significantly different.”
Tobe and colleagues wrote that their findings suggest a high ACR can be an independent predictor of poor outcomes after TAVR. Protein-to-creatine ratio (PCR) and dipstick proteinuria also appear to be useful for determining a patient’s risk of adverse outcomes; a PCR of 150 mg/g or less and positive dipstick proteinuria were both associated with a greater risk of the study’s primary outcome.
The team also noted that their work had certain limitations, including its relatively small sample size and the fact that only one facility was involved. Urine samples were also collected at different times of day, a detail the could have potentially impacted their results.
“Further research regarding which indicator is the most effective predictor or regarding the most appropriate cut-off value of each indicator is needed with a larger number of patients,” the authors concluded.