In July 2018, the Food and Drug Administration (FDA) announced that they were investigating certain pet foods that may be linked to canine dilated cardiomyopathy (DCM). Our team at Billings Animal Family Hospital wants to provide information about this research, to help ensure your dog is protected.

What is dilated cardiomyopathy in dogs?

DCM is a primary disease that affects the heart muscle, causing the heart chambers to dilate, and decreasing the heart’s ability to generate pressure to pump blood through the vascular system. DCM is most commonly characterized by ventricle dilation and concurrent ventricle wall thinning, but all four chambers can dilate. As the heart loses the ability to pump blood effectively, insufficient oxygenated blood is delivered to the body. Signs related to this issue include lethargy, weakness, weight loss, and collapse. As the dilation continues, heart valves start to leak, and fluid accumulates in the chest and abdomen, a condition known as congestive heart failure (CHF). Signs related to this issue include coughing, increased respiratory rate and effort, and abdominal distention. DCM has a higher incidence in certain breeds, such as Doberman pinschers, Great Danes, boxers, and cocker spaniels, indicating an inheritable genetic component. 

What is nutritional dilated cardiomyopathy in dogs?

As early as 2014, the FDA started receiving reports of DCM cases in breeds with no genetic predisposition to the disease. While the exact cause is still under investigation, researchers believe this is a complex medical condition likely affected by multiple factors, including genetics, underlying medical conditions, and diet. Lisa Freeman, DVM, PhD, DACVN, a professor at Cummings School of Veterinary Medicine at Tufts University, and several cardiologist colleagues researched this issue further, publishing an article in December 2018 in the Journal of the American Veterinary Medical Association. While the focus had been on the association of grain-free diets with this problem, Dr. Freeman suspects many diets, which she calls “BEG”(i.e., boutique, exotic ingredient, or grain-free) diets, may be to blame. In addition, vegetarian, vegan, and raw meat diets may play a role in nutritional DCM. The researchers concluded that market-driven fads inspire many pet food diets that are not supported by nutritional science, leading to health issues in pets who eat them. They also noted that while an association appeared to exist between DCM and feeding BEG, vegetarian, vegan, or home-prepared diets to dogs, they could identify no particular cause-and-effect relationship between the diets and the disease. This means that other factors may be equally as important, and numerous questions are still left unanswered, such as:

  • Are these pet foods deficient in specific nutrients?
  • Are the nutrients present in the diet, but not adequately digestible or usable by the dog?
  • Is something inhibiting uptake or usage of the amino acid taurine, which is important for heart cell function?
  • Are nutrient interactions in dog foods causing the problem?
  • Are toxins present in the food?
  • Are certain dogs genetically predisposed to this nutritional imbalance?

How is dilated cardiomyopathy in dogs diagnosed?

Regular wellness exams are important, so that issues such as DCM are diagnosed in the early stages when the condition can be better managed and treated. Diagnostic tools include:

  • Physical examination — Findings can include irregular heart rhythm, a weak pulse, a heart murmur, and jugular pulses. If CHF is present, signs can include muffled heart and lung sounds, and crackles in the lungs.
  • X-rays — Chest X-rays can reveal generalized heart enlargement, and, potentially, fluid in the lungs.
  • Echocardiography — A heart ultrasound is necessary to differentiate DCM from other cardiovascular diseases.
  • Holter monitoring — Twenty-four-hour electrocardiogram monitoring may be recommended to more accurately assess your dog’s cardiac rhythm.

How is dilated cardiomyopathy in dogs treated?

DCM treatment is aimed at improving the heart’s ability to pump blood through the body, dilating the peripheral blood vessels to decrease the heart’s workload, eliminating any fluid accumulation present in the lungs, and controlling heart rate and cardiac arrhythmias. Several cardiac medications that can be administered intravenously or orally are available. Dogs affected by nutritional DCM tend to benefit from a change to a diet made by a well-established manufacturer that contains standard ingredients. Taurine supplementation may help these dogs, as well.

How can I protect my dog from nutritional dilated cardiomyopathy?

We still have much to learn about nutritional cardiomyopathy, but you can take steps to protect your dog:

  1. The right diet — Consult our veterinary professionals, to ensure your dog’s diet is appropriate.
  2. The right time — Bring in your dog for regular wellness checks so we can diagnose issues, such as DCM, in the early stages when they are easier to manage.
  3. The time is now — If your dog is exhibiting signs, such as difficulty breathing, coughing, fainting, or distended abdomen, bring them to our hospital immediately, so we can evaluate their condition.
  4. Consider the others —If one dog in your household is diagnosed with possible nutritional DCM, other household dogs should be evaluated for the disease.
  5. The recommendations — If your dog is diagnosed with possible nutritional DCM, our veterinary professionals may recommend feeding them a different diet made by a well-established manufacturer that contains standard ingredients, such as chicken, beef, rice, corn, and wheat.

These FDA reports are understandably concerning, but by consulting with our veterinary professionals and ensuring your dog receives regular wellness exams, you can protect your dog from this potentially life-threatening disease. If you would like to schedule a wellness exam for your dog, contact our team at Billings Animal Family Hospital, so we can ensure their heart is pumping well.