Court documents also showed that the three cardiologists were derogatorily referred to as "the Indians."
An estimated 60,000 Indian-origin doctors are among about a million doctors in the US.
Arun Sharma, 56, committed a health care fraud over a 10-year-period in Texas.
He was charged with issuing illegal prescriptions for controlled substances.
In Photos: The Asus Zenfone 3 With Glass-and-Metal Design
Enduring Images of Rio Olympics 2016
Monsoon Fury: Floods in Many Parts of North India
Rio Olympics 2016 Close With Spectacular Ceremony
SRK to Priyanka Chopra: See What Celebrities Shared on Instagram This Week