Color flow doppler needed as part of stress test for women?

My wife had a referral to have a doppler stress test done. When they
did the test, they performed a color flow doppler in addition to the
doppler.

Aetna would not pay for the color flow doppler or reading of it
because they say it is considered "experimental" or a research type of
procedure. They say it provides no more information than the other
test that was paid for.

The hospital said that the color flow doppler is needed because the
standard doppler creates too many false positives for women.

I am in the middle here. Who is correct? What percentage of women
have the color flow doppler done and why?

Thanks for any help here. I did not want to become an expert, but I
am being forced into it.

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