Renal Artery Stenosis

Overview 

Renal artery stenosis (RAS) (also known as renovascular disease, renovascular hypertension, and ischemic nephropathy) develops when there is a narrowing or blockage of the arteries that supply blood to the kidneys.

This is one manifestation of cardiovascular disease (CVD) and involves the build-up of fatty deposits, called plaque in the kidney arteries. This plaque buildup (atherosclerosis) can eventually narrow and block the kidney arteries, resulting in restricted or blocked blood flow to these important organs. About 90% of RAS cases are caused by atherosclerosis¹, and risk factors for developing this condition include smoking, being overweight, high blood pressure, high cholesterol levels, diabetes, age, gender, and a family history of heart disease. Non-atherosclerotic diseases such as fibromuscular dysplasia (FMD) can also induce the obstruction of blood flow to the kidney. Another rare cause of arterial blockage occurs when the artery itself is inflamed and is caused by vasculitis.

Regardless of the cause, once the kidney senses a certain level of obstruction, it releases hormones that will raise the blood pressure, increasing your risk of having a heart attack or stroke. In addition, the narrowing from RAS can build up to the point that the blood flow diminishes, and the affected kidney can no longer function and shrinks in size. This can be assessed by renal ultrasound. Individuals with this condition in both kidneys could end up needing dialysis.

The kidneys are vital organs that filter the blood of certain toxins and ensure a proper balance of fluid leaving the body as urine. The kidneys also secrete important hormones that regulate vital functions, including blood pressure. If kidney artery disease is not discovered in time, it can damage your kidneys and how they function.

References

1. National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health (NIH).