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Renal artery stenosis

Renal artery stenosis (RAS) is a situation in which the person's renal artery undergoes narrowing. This issue can hinder the flow of blood to the kidney related to that artery. It can lead to particular complications, such as kidney atrophy and high blood pressure. Eventually, it can lead to failure of the kidney.


In many cases of renal artery stenosis, the patient does not present with any particular symptoms. The usual issue that can occur is high blood pressure (hypertension) that does not resolve despite treatment with medication. In some instances, both kidneys are affected by RAS, and when this is the case renal function may worsen. High blood pressure treatment that uses an ACE inhibitor can also lead to worsened function of these organs in people with RAS, so it is contraindicated in those who have the condition. Consider that this is not an exhaustive list of potential symptoms.


The major cause of renal artery stenosis is atherosclerosis, which is a thickening of artery walls due to fatty material build up (like cholesterol). This more frequently occurs in those who, at an age of 50 or above, have a sudden onset of high blood pressure. However, in younger patients, fibromuscular dysplasia is the main cause of RAS. This situation can also lead to narrowing of other arteries, such as the carotid ones, and less frequently those in the abdomen. Other medical reasons are also possible, so having renal artery stenosis does not mean that one of these issues led to it.


A medical professional is the one to make a diagnosis of RAS. One of the possibilities that may suggest this condition, as discussed earlier, is a case of high blood pressure which cannot be controlled well through medication. Certain testing can be done, for instance, an arteriogram of the renal artery is possible. A captopril challenge test, or CCT, may also be used, but is typically considered useful only in incidents involving adults, and not children.


Which treatment method is used varies based upon factors like the underlying medical condition that led to the renal artery stenosis. For instance, when it is brought on by atherosclerosis, medication is the common course of treatment. When fibromuscular dysplasia is behind the case of RAS, then angioplasty is typically employed. Treatment may vary from case to case, and professional advice is required, so don't attempt to select a method based on what you read here.

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