Renal artery stenosis

In this angiography, you can see a "string of beads" appearance to the renal artery, the classic sign of fibromuscular dysplasia.

Definition

Where a narrowing of the renal artery causes problems.

Epidemiology

Pretty common, generally seen around the age of 50.

Pathophysiology

The artery supplying the kidneys gets smaller. Usually this is due to atherosclerosis, where cholesterol deposits in the artery cause a narrowing.

It can be down to fibromuscular dysplasia in young females - if so it will cause a "beaded" appearance of the renal artery on angiography.

Clinical Features

Classically, they are generally asymptomatic, with a patient just suffering from secondary hypertension, that isn't easily controlled with medication.

Investigations

Angiography can often show a narrowing of the blood vessel, or the beaded appearance of fibromuscular dysplasia.

Management

As said before, it can be hard to treat clinically. Often, patients will be started on an ACE inhibitor since the doctor assumes its essential hypertension. This can cause a deterioration in renal function, so ACE inhibitors should not be given with renal artery stenosis.

The best management is to try to prevent further atherosclerosis, adjusting risk factors such as cholesterol and smoking using standard prevention treatments.

If renal function deteriorates, blood pressure can't be controlled, or the cause is fibromuscular dysplasia, the treatment is angioplasty (surgical vessel widening), with or without stenting.