You may be caught by surprise if your doctor says you have blockages in the vessels that supply blood to your kidneys – vessels known as the renal (pronounced REE-nul) arteries. Like most people with this condition, you may not have any symptoms.
About five percent of all patients with high blood pressure have blockages in the kidneys, and 30 percent or more of patients who have blockages in other arteries also have blockages in their kidney arteries.
Blockages to the kidney are an important concern, especially for patients who have high blood pressure, heart failure and other conditions that can put stress on the kidneys.
Treatments are available to help prevent or slow the progression of the disease. However, without treatment, renal artery disease may cause high blood pressure and eventually lead to kidney failure. Both are serious. High blood pressure is a risk factor for heart disease, heart attack and stroke. And when the kidneys fail, they are no longer able to filter the blood and rid the body of waste products. People with kidney failure require treatment with either:
- Kidney dialysis, in which a machine assumes the role of filtering the blood of impurities, or
- Kidney transplant, in which the diseased kidney is surgically replaced with a healthy, donated kidney.
Other terms that you may hear that describe blockages in the arteries to the kidneys include:
- Renovascular disease
- Renovascular hypertension
- Ischemic nephropathy
- Renal artery stenosis
What are the Renal Arteries and Kidneys
The renal arteries are vessels that supply blood to the kidneys. They branch from the abdominal aorta, the main vessel carrying blood from the heart to the lower body. Before reaching the kidneys, each renal artery divides into four or five branches.
Our two kidneys, one located on each side of the lower spine at about the level of the last rib, are vital organs that perform a number of life-saving jobs. They include:
Filtering blood to remove wastes, drugs and other impurities and eliminating excess fluid from our bodies to keep a stable balance of bodily chemicals and fluids. Each day, the kidneys filter about 200 quarts of fluid. About two quarts are eliminated through the urine. The other 198 quarts are returned to the bloodstream.
The process by which the kidneys filter blood involves small structures called nephrons (up to a million in each kidney). A nephron includes a filtering unit made up of tiny blood vessels, called a glomerulus. The glomerulus is attached to minute tubes (tubules). Blood passing through the glomerulus is filtered. The remaining fluid then travels through the tubules. There, chemicals and water are either added to or removed from the fluid to meet the body’s needs. Urine results from this process and is stored in the bladder from one to eight hours.
Regulation of salt, potassium and acid in the body.
Production of hormones needed by other organs. The kidneys produce hormones for red blood cell production, blood pressure regulation and calcium metabolism. They also produce a form of vitamin D that promotes bone health.