I didn't know the FDA cared about dogs, but they published a list of food brands that cause cardiomyopathy. Most of the brands listed are considered premium brands and advertise themselves as being grain free. Here's the list and a link.
https://www.cbc.ca/news/health/dog-food-dcm-fda-1.5199186
https://www.cbc.ca/news/health/dog-food-dcm-fda-1.5199186