Abstract 20258: Stenosis Severity and Kidney Function in Atherosclerotic Renal Artery Stenosis

Abstract

Introduction: Ischemic nephropathy due to atherosclerotic renal artery stenosis (ARAS) is associated with poor event free survival. However, previous studies suggest that stenosis severity has a poor relation to kidney function. We sought to test the interactions of stenosis severity, and revascularization, on kidney function in people with ARAS. Hypothesis: Stenosis severity is associated with poor renal function in people with ARAS. Methods: The Cardiovascular Outcomes in Renal Atherosclerotic Lesions (CORAL) clinical trial is a prospective trial of individuals with atherosclerotic renal-artery stenosis. Patients were followed to a maximum of 8 years. Angiographic images were measured at a single core lab (University of Virginia) using quantitative computer-assisted angiography. Estimated glomerular filtration rate (eGFR) was measured using creatinine and cystatin-C, performed at a single core lab (University of Minnesota), and calculated using the CKD-EPI Creatinine-Cystatin C formula. The analyses are controlled by age and gender. Results: At baseline CKD-EPI eGFR was strongly and negatively correlated with percent stenosis (-0.2472, p<0.0001) and positively correlated with minimal luminal diameter (0.2974, p<0.0001). Interestingly, peak systolic pressure gradient and mean pressure gradients were not (p=ns for both). At three years follow-up baseline percent stenosis remained significant by univariate analysis (0.1380, p=0.01), however, it was not significant by multivariate analysis. Conclusions: Stenosis severity is strongly related to kidney function at the time of presentation in patients with atherosclerotic renal artery stenosis. However, by three years follow-up, this relationship appears to be lost.