The renal arteries are the vessels that carry blood to the kidneys. The renal arteries can develop decreased blood or complete obstruction. Renal artery stenosis (RAS) is caused by the accumulation of fatty deposits (plaques) and other substances in the artery (arteriosclerosis). Thickening of the muscle and fibrous tissue of the renal artery (fibro muscular dysplasia) is another cause. Renovascular hypertension if left untreated may contribute to a number of serious cardiovascular and kidney problems:
- Stroke
- Cardiac hypertrophy - thickening of heart muscle
- Acceleration of arteriosclerosis - in all of the body’s arteries thus increasing the risk of heart attack, aneurysm and other vascular diseases.
- Renal - requiring dialysis
Symptoms:
- Blood pressure is not being controlled by diet, exercise and/or medication
- Suddenly uncontrolled hypertension
- New onset of hypertension, especially in a younger person
- Renal artery bruit (a noise heard over your abdomen that your doctor can hear with a stethoscope)
Risk Factors:
- Tobacco use
- High blood pressure
- Diabetes
- High cholesterol
- Overweight
- Personal history of peripheral vascular disease
How it is Diagnosed:
- History and physical exam
- Renal artery ultrasound
- Computed tomography angiography (CTA)
- Magnetic resonance angiography (MRA)
- Arteriogram/angiogram (dye is injected into the renal arteries and pictures are taken)
Treatment Options:
There are several approached to treatment, depending on the severity of the disease.
- Medical management - monitoring for progression of the disease
- Risk factor reduction - weight loss, lower blood pressure and cholesterol, exercise, smoking cessation and a low fat/cholesterol diet
- Medication - to lower blood pressure and cholesterol
- Renal angioplasty/stent - dye is injected into the renal arteries to determine where the blockage is. Then a small balloon on the end of a catheter is inserted into the effected renal artery. The balloon is positioned inside the blockage and then inflated, pressing the plaque up against the artery wall and opening up the artery. Once the artery is open, a tiny mesh tube, called a stent, is inserted into the artery. The stent keeps the plaque pressed up against the artery wall, helping th artery to stay open.
- Renal artery bypass surgery