AUSTIN, Texas — Certain dog food may be causing heart disease in breeds that are less likely to suffer from it, according to the U.S. Food and Drug Administration.

The agency is investigating the connection between diets containing peas, lentils, legumes, or potatoes as main ingredients and a disease called canine dilated cardiomyopathy.

DCM affects a dog's heart muscle and enlarges the heart. It's more common in large breeds.

But in some recent cases, the FDA saw it in smaller dogs, like golden and labrador retrievers.

The dog in each of these cases ate a grain-free diet, according to the FDA.

"This is more commonly a diagnosis that's picked up during an annual exam when we hear a heart murmur," Crestview Veterinary Clinic medical director Dr. Jordan Kautz told KVUE.

Kautz said he's only diagnosed 10-15 dogs with DCM in his career.

"It is nowhere near as common as other causes of heart failure in small breed dogs. But we certainly see a case from time to time," he said.

Coughing, fatigue, and difficulty breathing are common signs to look for in your dog. If it's not caught early, the disease can lead to heart failure.

The FDA is working with top veterinarians to better understand the potential connection.