Renovascular conditions are disorders or diseases affecting the blood vessels of the kidneys. Typically, renovascular conditions involve either narrowing of the kidney arteries or blockage of the kidney veins. Atherosclerosis, the accumulation of cholesterol and other fats along the lining of artery walls, is a main contributor to renovascular conditions.
Renovascular hypertension, or high blood pressure, is caused by narrowing of the arteries that carry blood to the kidneys. Renovascular hypertension is a form of secondary hypertension. Most forms of hypertension are considered “essential,” and the cause is unknown. But a small number of high blood pressure patients have “secondary hypertension,” which means an underlying disease is identified as the cause.
During renovascular hypertension, one or both of the kidney arteries become narrow. This reduces blood flow to the kidneys, and the affected kidney or kidneys mistakenly respond as if the patient’s blood pressure is low. They secrete hormones that tell the body to retain salt and water, which causes an increase in blood pressure.
Two groups of patients are at particular risk for renovascular hypertension: young women with a sudden onset of high blood pressure and older people with atherosclerosis (narrowing) in other arteries, such as the heart (coronary artery disease) or the legs (peripheral vascular disease).
Renal duplex, a sophisticated ultrasound technique, aids in the diagnosis of patients with renal artery stenosis. This noninvasive technology is useful in selecting patients for further evaluation and possible treatment. Renovascular hypertension often can be treated with angioplasty and/or stenting of the narrowed artery, performed by a qualified interventional radiologist.