Renal artery stenosis

Renal artery stenosis (RAS) is the narrowing of one or more of the renal arteries, which can reduce kidney blood flow and may lead to hypertension and kidney disease. RAS is often caused by atherosclerosis (approximately 90%) which is related to hypertension, high cholesterol, and smoking, or other rarer disease processes such as fibromuscular dysplasia (approximately 10%). The narrowing of one or more renal arteries can impede blood flow to a kidney, which the kidney can interpret as hypoperfusion, and through a cascade of events involving activation of the Renin Angiotensin Aldosterone System (RAAS) may result in renovascular hypertension – a secondary type of high blood pressure. Possible complications of renal artery stenosis are chronic kidney disease, kidney atrophy, resistant hypertension, cardiovascular events such as coronary artery disease and stroke, and fluid retention, often manifesting as lower extremity edema.