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Why ACE inhibitors contraindicated in bilateral renal artery stenosis?

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ACE inhibitors (Angiotensin-Converting Enzyme inhibitors) are a class of medications commonly used to treat high blood pressure, heart failure, and certain kidney conditions. However, they are contraindicated in cases of bilateral renal artery stenosis. Here's why:

Bilateral renal artery stenosis refers to the narrowing or blockage of both renal arteries, which supply blood to the kidneys. When both renal arteries are affected, it can significantly reduce blood flow to the kidneys, leading to decreased kidney function.

ACE inhibitors work by blocking the action of an enzyme called ACE, which is involved in the production of a hormone called angiotensin II. Angiotensin II causes blood vessels to constrict and promotes the release of another hormone called aldosterone, which leads to sodium and water retention.

In individuals with bilateral renal artery stenosis, the kidneys already have reduced blood flow. ACE inhibitors further dilate the blood vessels and decrease the blood pressure. This can result in a significant decrease in blood flow to the kidneys, potentially worsening kidney function.

Additionally, the dilation of blood vessels caused by ACE inhibitors can cause a compensatory response in the body, leading to increased production of angiotensin II. In the case of bilateral renal artery stenosis, this increased angiotensin II production can further constrict the already narrowed renal arteries, exacerbating the problem.

As a result, ACE inhibitors are contraindicated in bilateral renal artery stenosis to avoid potential harm to the kidneys and to prevent a further decline in renal function. Other medications or treatment options may be considered for managing blood pressure and kidney function in individuals with this condition.

It's important to note that this information is not a substitute for medical advice. If you have any concerns or questions about your specific medical condition or treatment, please consult with a healthcare professional.

User Dexter
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Final answer:

ACE inhibitors are contraindicated in bilateral renal artery stenosis because they reduce angiotensin II levels, which is necessary to maintain GFR in the presence of narrowed renal arteries, leading to a risk of renal failure.ACE

Step-by-step explanation:

The question pertains to the use of ACE inhibitors in the context of bilateral renal artery stenosis. ACE inhibitors, drugs such as Lisinopril and Enalapril, are prescribed to manage high blood pressure by blocking the conversion of angiotensin I to angiotensin II, thereby reducing systemic vascular resistance and lowering blood pressure.

inhibitors are contraindicated in bilateral renal artery stenosis because angiotensin II is needed to maintain sufficient glomerular filtration rate (GFR) in the presence of renal artery stenosis. By blocking the formation of angiotensin II, ACE inhibitors may further decrease GFR, causing renal failure and compromised kidney function. The reduced GFR can impede kidney function by not allowing sufficient blood flow through the narrowed arteries, ultimately leading to kidney injury or failure.

User Makarov Sergey
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