The FDA has announced that they are now investigating the potential link between grain-free diets and canine heart disease. The potentially fatal heart condition, Taurine-Deficient Dilated Cardiomyopathy, is known to develop in dogs who have defective taurine synthesis pathways. It has also been documented in certain breeds, such as Golden Retrievers, who are fed a lamb and rice diet.
Recently, cardiologists have noticed an uptick in Dilated Cardiomyopathy (DCM) in breeds not typically associated with the disease. Because DCM can occur secondary to other diseases, such as hypothyroidism or infectious Chagas disease, a primary cause for DCM must always be excluded. Cardiologists began to see a correlation between certain diets and the development of DCM in a number of different dog breeds over the last few years. Affected dogs were more likely to be eating a boutique or grain-free dietand diets with exotic ingredients. Lentils, kangaroo, duck, pea, tapioca, salmon, lamb, barley, bison, chickpeas, and fava beans, were common ingredients. Vegan and home-cooked diets have also been associated. While the mechanism is yet unknown, it is believed it may be caused by factors that include decreased amino acid absorption and decreased taurine synthesis. To complicate matters, whole blood taurine and plasma levels may test low in some dogs and normal in others.
While DCM generally carries a poor-to-grave long-term outcome, changing diet and supplementation with taurine can often improve cardiac function, with some dogs being able to taper off heart medication after 6 months.
Symptoms of DCM can include decreased energy, increased breathing rate, labored breathing, irregular heart rate, coughing, and weight loss. Dogs are often asymptomatic until later stages of the disease. A heart murmur or arrhythmia and changes in lung sounds may be detected during an examination.
If your dog has been eating grain-free food and shows any of these symptoms, please contact your veterinarian immediately. You can also see our blog post about steps you can take.
Dogs with suspected DCM should receieve chest x-rays, ECG, blood pressure and a comprehensive echocardiogram. It is essential that the echocardiogram be performed by an experience ultrasonographer who is profecient in 2D, m-mode, color Doppler and spectral Dopper imaging. Ideally, a cardiologist would evaluate the x-rays, ecg and echo findings. Congenital defects need to be ruled out by x-ray/echo imaging in young and middle-aged dogs. Affected dogs should also have complete labwork (CBC, chem, lytes, T4 and urinalysis) performed and a travel history should be obtained.
Please contact us if you would like to schedule your dog's echocardiogram or if you have questions about the link between taurine and DCM in dogs.
Tufts Article: Risk of heart disease in boutique and grain-free diets and exotic ingredients
Taurine-Deficient Dilated Cardiomyopathy in Golden Retrievers
FDA Reporting Portal