Non-Hemodynamically Significant Renal Artery Stenosis Predicts Cardiovascular Events in Persons with Ischemic Heart Disease

BACKGROUND/AIMS: Recently, we reported that small renal arteries, defined by a low reference diameter (RD) or minimal luminal diameter (MD), are independently associated with a low GFR, resistant hypertension, and onset of contrast-induced nephropathy and suggested a post-hoc analysis of CORAL trial based on RD categories. Here we hypothesized that RD and MD are markers of nontraditional cardiovascular risk factors and tested whether low RD and MD could impact the prognosis of patients with ischemic heart disease. METHODS: Prospective cohort study. We used proportional hazards models to analyze the first onset of cardiovascular events in relation with RD, MD, or percentage of renal artery stenosis (RAS) in those with low-to-moderate RAS (10-70%) (n = 181). RESULTS: During the median follow-up of 4.5 (range, 0.1-5) years, 27.8% participants (n = 623; mean age, 64 years; 29% women) experienced a cardiovascular event (35.4% in those with RAS 10-70%). The presence of low-to-moderate RAS was associated with cardiovascular events. In these subjects, those with low MD were associated with a higher risk of cardiovascular events (MD >4.2 mm, HR: 1; MD 3.2-4.2 mm, HR: 1.66, 95% CI: 0.74-3.72, p = 0.22; MD <3.2 mm, HR: 3.72, 95% CI: 1.65-8.40, p = 0.002). When MD was added to a standard risk-factor model, risk prediction improvement was by 4.1%. Results were qualitatively similar if MD was replaced by RD or percentage of stenosis, but with smaller improvement of risk prediction and model fit. CONCLUSIONS: In patients with ischemic heart disease and low-to-moderate RAS, MD is a significant predictor of cardiovascular events, improves risk prediction, and may represent a valuable biomarker of cardiovascular disease risk.