Vascular Disease Foundation - Fighting Vascular Disease... Improving Vascular Health.
VDF Infomation Library

Disease Information : RAS : What is it?

RAS : What is it?

What is Renovascular Hypertension ?

Hypertension (high blood pressure) is the most common reason for health care office visits in the United States. Over 50 million Americans, and over 1 billion people worldwide have hypertension. Recently, the seventh report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of Hypertension changed the definition of hypertension to <120/80 mmHg. This will increase the number of Americans who are considered hypertensive. All people with hypertension are candidates for aggressive risk factor intervention and drug treatment for newly diagnosed hypertension.

The vast majority of patients with hypertension have “primary” hypertension. That is, there is no underlying medical reason for hypertension. They just have high blood pressure. Approximately 10% of patients have “secondary” hypertension, where an underlying reason, which if identified and treated, would cure or lower the high blood pressure. The two most common causes of secondary hypertension are chronic kidney disease and medication side effect. Drugs that can cause hypertension include non-steroidal anti-inflammatory drugs (ibuprofen, naproxen); sympathomimetics (decongestants, antihistamines); oral contraceptives, anabolic steroids, illicit substances (cocaine); and over the counter dietary supplements (ephedra).

One important cause of secondary hypertension is renal artery stenosis (RAS), which has good results from treatment. Stenosis means narrowing, or partial blockage of the blood vessel that carries blood to the kidney. Atherosclerosis, or hardening of the arteries, is the most common cause of RAS. This typically occurs in older people. RAS is often found in patients with vascular disease in other areas (for example: coronary, carotid, abdominal aorta, peripheral arteries). RAS may also occur in younger (commonly female) patients, due to abnormal development of the artery wall known as fibromuscular dysplasia.