Incidental Atherosclerotic Renal Artery Stenosis Diagnosed at Cardiac Catheterization: No Difference in Kidney Function with or without Stenting

Abstract

The long-term kidney function of patients with atherosclerotic renal artery stenosis (ARAS) diagnosed incidentally at the time of cardiac catheterization is not well described despite the increasingly common practice of assessing these vessels at the time of cardiac investigation.This is a retrospective analysis of a cohort identified prospectively at the time of non-emergent coronary angiography. Those with >or=50% ARAS were managed medically and underwent stenting if recommended by their nephrologist and/or cardiologist. Longitudinal regression analysis was used to compare the annualized change in estimated glomerular filtration rate (GFR) in stented and unstented patients. Cox regression analysis was used to determine the predictors of a decline in GFR by >or=25%.Of 140 patients, 67 (48%) were stented, mostly for preservation of kidney function (70.1%) and/or resistant hypertension (53.7%). Median follow-up time was 943 days. Stented patients were younger, had higher systolic blood pressure and more severe ARAS. The adjusted rate of change in GFR was -1.49 (95% CI -2.33 to -0.65) ml/min/1.73 m(2)/year in the unstented group, and -1.48 (95% CI -2.34 to -0.62) ml/min/1.73 m(2)/year in the stented group (p = 0.99). A decline of GFR >or=25% occurred in 42 (30%) patients; no patient required dialysis. Only the presence of cereberovascular disease was associated with this outcome (hazard ratio 2.52, 95% CI 1.56-5.41).We were unable to demonstrate a benefit or harm of renal artery stenting for ARAS, thus further increasing the uncertainty of the significance of these lesions and how they are best managed.