Renal Artery Disease & Renal Artery Stenosis

Many people have no symptoms. In selected patients, severe narrowing may contribute to difficult-to-control high blood pressure, deterioration in kidney function or sudden episodes of fluid accumulation in the lungs.

When kidney blood flow falls, the kidney can activate hormonal pathways that drive blood pressure up. The central question in renal artery disease is therefore not whether a narrowing exists, but whether it is actually causing the blood pressure or kidney problems, because only then is a procedure likely to help.

Atherosclerotic renal artery stenosis

Atherosclerotic plaque usually affects the origin of the renal artery and commonly occurs alongside disease in the aorta, coronary arteries or leg arteries.

The presence of narrowing does not automatically mean a procedure is required.

Fibromuscular dysplasia

Fibromuscular dysplasia is a non-atherosclerotic arterial disorder more often diagnosed in younger or middle-aged women. It can cause renal artery narrowing and high blood pressure.

Management differs from atherosclerotic disease and may include angioplasty in selected cases.

Possible clinical features

Features may include resistant hypertension, a sudden increase in blood pressure, unexplained worsening kidney function, recurrent flash pulmonary oedema or a difference in kidney size.

These findings can have other causes and require careful medical assessment.

Renal artery stenosis rarely announces itself directly. The clues are clinical: hypertension that resists multiple medications, a sudden deterioration in previously stable blood pressure, declining kidney function, recurrent episodes of sudden fluid in the lungs (flash pulmonary oedema) or a size difference between the kidneys on imaging.

Each of these findings has other possible causes, so the pattern is assessed as a whole rather than any single result. Severe sudden breathlessness is an emergency and should be managed through Triple Zero (000).

Renal duplex ultrasound estimates blood flow through the renal arteries and is a common first test. CT or MR angiography defines the anatomy in more detail, while blood and urine tests, and the pattern of blood pressure readings, indicate whether the narrowing is clinically important.

Catheter angiography is reserved for patients in whom intervention is already being considered. Kidney function guides the choice and timing of contrast-based imaging, and assessment is often shared with renal physicians.

Most patients with atherosclerotic renal artery stenosis are managed medically, with blood pressure treatment, cholesterol management, smoking cessation and diabetes care. Angioplasty, with or without stenting, is reserved for selected situations where the narrowing is judged to be driving significant clinical problems.

Fibromuscular dysplasia is managed differently from atherosclerotic disease and may respond well to angioplasty in selected cases.

Medical management

Medical care typically combines blood pressure medication, cholesterol-lowering therapy, antiplatelet treatment when appropriate, smoking cessation and diabetes management.

Renal artery angioplasty and stenting

Angioplasty with or without stenting may be considered when there is recurrent pulmonary oedema, progressive kidney dysfunction attributable to the narrowing, severe resistant hypertension or certain anatomical situations.

The likely benefit must be weighed against risks such as artery injury, contrast-related kidney stress and embolisation.

Open reconstruction

Open renal artery reconstruction is uncommon but may be considered for complex aneurysms, branch disease, failed endovascular treatment or when another open aortic operation is being performed.

Progressive renal artery disease can contribute to kidney dysfunction and cardiovascular complications. Intervention carries its own hazards, including bleeding, contrast-related kidney injury, arterial damage, embolisation and restenosis, so a procedure is not recommended simply because a narrowing is visible on a scan.

Ongoing care involves monitoring blood pressure, kidney function and, where relevant, the treated or surveilled artery with ultrasound. Kidney function and potassium may need checking when certain blood pressure medicines are used.

Sensible questions include whether the narrowing is severe enough to explain your blood pressure or kidney findings, what medical treatment can achieve first, and in what circumstances angioplasty or stenting would be recommended for you.

You might also ask how your kidney function will be monitored, whether any blood pressure medicines need adjusting, and what follow-up imaging is planned. Bring your blood pressure diary and recent blood test results if you have them.

A renal artery narrowing seen on a scan is common; a narrowing that is truly responsible for resistant hypertension or declining kidney function is less so. Distinguishing the two prevents unnecessary procedures and identifies the patients who genuinely stand to benefit. That judgement is made with you, often together with your GP and renal physician.

Yarra Vascular Surgeons assesses renal artery disease with duplex ultrasound and cross-sectional imaging, and provides medical management, surveillance, angioplasty, stenting and, where needed, open reconstruction. Care is coordinated with renal physicians so that blood pressure, kidney function and arterial anatomy are considered together.

Renal artery narrowing should be treated according to its clinical effect, not simply its appearance on a scan. Yarra Vascular Surgeons assesses blood pressure patterns, kidney function and arterial anatomy to determine whether medical management, surveillance, angioplasty, stenting or reconstruction is appropriate. This measured approach is particularly important in resistant hypertension, declining kidney function or recurrent pulmonary oedema.