Renal Artery Disease

What is Renal Artery Disease?

Renal artery disease, also known as renal artery stenosis, is a condition in which one or both of the arteries that supply blood to the kidneys become narrowed or blocked. This reduced blood flow can trigger a chain of serious health consequences, including high blood pressure that is difficult to control (renovascular hypertension) and progressive kidney damage that may lead to kidney failure.

The kidneys play a vital role in filtering waste from the blood, regulating blood pressure, and maintaining fluid and electrolyte balance. When the renal arteries are narrowed, the kidneys receive less blood flow and respond by releasing hormones that raise blood pressure throughout the body — the kidneys essentially “think” blood pressure is too low and attempt to compensate. This creates a cycle of worsening hypertension that can damage the kidneys further and increase the risk of heart disease and stroke.

Causes of Renal Artery Disease

Atherosclerosis

The most common cause of renal artery disease is atherosclerosis — the gradual buildup of cholesterol, fat, and other substances (plaque) on the inner walls of the arteries. Atherosclerosis accounts for approximately 90% of renal artery stenosis cases [1] and typically affects patients over age 50. The blockage usually occurs at the opening of the renal artery where it branches from the aorta.

Fibromuscular Dysplasia (FMD)

A less common cause is fibromuscular dysplasia, a condition in which the cells in the artery wall grow abnormally, creating a “string of beads” appearance and narrowing the vessel. FMD is more common in younger women and typically affects the middle and distal portions of the renal artery.

Symptoms

Renal artery disease often develops gradually, and many patients have no symptoms in the early stages. The condition is frequently discovered during evaluation for other problems. When symptoms do appear, they may include:

• Resistant hypertension — high blood pressure that does not respond well to three or more medications
• Sudden onset of high blood pressure before age 30 or after age 55
• Worsening kidney function detected on blood tests
• Fluid retention and swelling (edema), especially in the legs and ankles
• Congestive heart failure symptoms, including shortness of breath
• Recurrent episodes of flash pulmonary edema (sudden fluid in the lungs)
• Muscle cramping
• Inconsistent or decreased urination
• Headaches
• Fatigue and general malaise
• Unintentional weight loss

When to Seek Evaluation

You should discuss renal artery disease screening with your doctor if you have high blood pressure that:

• Was diagnosed at a young age
• Suddenly worsens or becomes difficult to control
• Requires three or more medications
• Is accompanied by declining kidney function
• Does not respond to typical blood pressure medications

Risk Factors

Several factors increase your risk of developing renal artery disease:

• Age — risk increases significantly after age 50
• High blood pressure — both a cause and consequence of the condition
• High cholesterol — contributes to atherosclerotic plaque buildup
• Diabetes — accelerates damage to blood vessel walls
• Smoking — damages arteries and accelerates atherosclerosis
• Obesity — increases cardiovascular strain
• Family history of coronary artery disease, peripheral artery disease, or renal artery disease
• Existing atherosclerosis in other arteries (coronary, carotid, or peripheral)
• Neurofibromatosis — a genetic disorder that can affect blood vessel development

Diagnosis

Early diagnosis of renal artery disease is important for preserving kidney function and controlling blood pressure. At Preferred Vascular Group, our diagnostic evaluation may include:

• Duplex Ultrasound: A non-invasive test that uses sound waves to visualize blood flow in the renal arteries and measure the degree of narrowing. This is often the first-line screening test.
• CT Angiography (CTA): Provides detailed, three-dimensional images of the renal arteries and can accurately identify the location and severity of stenosis.
• Magnetic Resonance Angiography (MRA): Creates detailed images of blood vessels using magnetic fields, without the need for ionizing radiation. Particularly useful for patients with kidney concerns, as certain contrast agents can be avoided.
• Renal Arteriography: The definitive diagnostic test, in which contrast dye is injected directly into the renal arteries through a catheter to visualize blockages in real time. This test can also be combined with treatment in the same session.
• Blood tests: To assess kidney function (creatinine, BUN, GFR) and check for renin levels that may indicate renovascular hypertension.

Treatment Options

Treatment for renal artery disease aims to restore adequate blood flow to the kidneys, normalize blood pressure, and preserve kidney function. The approach depends on the severity of the stenosis and the patient’s overall health.

Medication Management

Initial treatment often involves medications to:

• Control blood pressure using ACE inhibitors, ARBs, calcium channel blockers, or other antihypertensives
• Lower cholesterol with statin medications to slow plaque progression
• Prevent blood clots with aspirin or other antiplatelet agents
• Manage diabetes to reduce further vascular damage

For some patients with mild to moderate stenosis, medication management alone may effectively control blood pressure and stabilize kidney function.

Minimally Invasive Treatment

When medications are not sufficient or kidney function is declining, our vascular specialists offer advanced interventional procedures:

• Angioplasty with Stenting: A catheter is guided through a blood vessel to the narrowed renal artery. A small balloon is inflated to open the blockage, and a stent (a small mesh tube) is placed to keep the artery open. This is the most common interventional treatment for renal artery stenosis and has generally replaced surgical bypass as the first-line procedure.

This procedure offers several advantages:

• Performed on an outpatient basis in most cases
• No surgical incision — just a small nick in the skin at the access point
• No general anesthesia required
• Patients typically return to normal activities within a few days
• Can significantly improve blood pressure control and preserve kidney function

Surgical Options

In rare cases where endovascular treatment is not feasible, surgical bypass or other open procedures may be considered. Surgery involves creating a new pathway for blood to reach the kidney, bypassing the blocked artery.

Potential Complications of Untreated Renal Artery Disease

Without treatment, renal artery disease can lead to:

• Progressive, irreversible kidney damage
• End-stage renal disease requiring dialysis
• Uncontrolled hypertension increasing the risk of heart attack and stroke
• Heart failure
• Kidney atrophy (shrinkage of the affected kidney)

Why Choose Preferred Vascular Group?

At Preferred Vascular Group, our board-certified vascular specialists have extensive experience diagnosing and treating renal artery disease. We offer:

• Advanced diagnostic imaging for accurate assessment of renal artery stenosis
• Minimally invasive angioplasty and stenting with high success rates
• Coordinated care with your nephrologist and primary care physician
• Proactive monitoring of kidney function and blood pressure after treatment
• Eight convenient locations across Georgia and Ohio

Early detection and treatment of renal artery disease can protect your kidneys and significantly improve blood pressure control. If you have risk factors or symptoms suggestive of renal artery disease, our specialists can provide a thorough evaluation and personalized treatment plan.

References

1. Renal Artery Stenosis. StatPearls, StatPearls Publishing, 2024. NCBI Bookshelf
2. Renovascular Hypertension. StatPearls, StatPearls Publishing, 2024. NCBI Bookshelf
3. Safian RD, Textor SC. “Renal-artery stenosis.” New England Journal of Medicine, 2001. PubMed