Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Renal Artery Stenosis ?
    ### Response:
    Renal artery stenosis is the narrowing of one or both renal arteries. Renal means kidney and stenosis means narrowing. The renal arteries are blood vessels that carry blood to the kidneys from the aortathe main blood vessel that carries blood from the heart to arteries throughout the body.
    