Canine dilated cardiomyopathy is also known as DCM. It is a disease of the cardiac muscle that causes the tissue to degenerate and become thin. This can happen in any part of the heart, but the left ventricle seems to be most commonly affected. When the heart muscles become weak and thin, the heart walls stretch and cause the heart to become enlarged or dilated.
This was once thought of as an inheritable condition, but new research is showing that DCM is also diet-related. Grain-free, “boutique diets,” and those that consist of exotic ingredients appear to predispose all breeds of dogs to dilated cardiomyopathy. Foods containing peas, lentils, legume seeds, and potatoes as the main ingredients seem to be of primary concern.
Breeds predisposed to DCM are typically large breed dogs such as Doberman Pinschers, Boxers, Irish Wolfhounds, Saint Bernards and Great Danes. There are also a few medium-sized dogs that can develop DCM. Cocker Spaniels, English Springer Spaniels, and Portuguese Water dogs can be affected. In rare instances, small breed dogs develop DCM. It appears that DCM is more prevalent in males than in females.
Taurine deficiency is still considered a factor in the development of DCM. Some breeds are predisposed to taurine deficiency, such as Golden Retrievers, Cocker Spaniels, Newfoundlands, Saint Bernards, Irish Wolfhounds and English Setters.
In some instances, diets that are low in taurine have made this condition more commonplace. Various “boutique diets” have been associated with low taurine blood levels in dogs.
A dog with dilated cardiomyopathy may show a sudden onset of clinical signs, even though the disease progresses slowly. Symptoms of DCM include rapid respiratory rate (greater than 30 breaths per minute), increased respiratory effort, coughing, blue tongue/gums, weakness, exercise intolerance, episodes of collapse, weight loss, reduced appetite, distended belly, inactivity or sudden death.
If you notice any of these signs, it is best to have your pet evaluated by your veterinarian. Auscultation of the heart will allow your veterinarian to identify a heart murmur and assess the lungs for fluid. Chest X-rays are needed to examine the size and shape of the heart, as well as lungs. An echocardiogram and ECG are required in order to definitively diagnosis the specific cause of heart enlargement or arrhythmia. An ECG or electrocardiogram evaluates the electrical activity of the heart and is used to diagnosis abnormal rhythms. An echocardiogram is an ultrasound of the heart which can determine the size of each chamber, wall thickness, pressure through each valve, determine pumping efficiency, and evaluate valve integrity. Various blood tests may be assessed to check for any other problems or issues.
Once DCM is confirmed, treatment with a variety of medications is begun. The medicines used depending on the severity of the condition.
Once a dog is diagnosed with DCM, the average lifespan can range from three months to two years. Early detection and intervention are crucial in improving the dog’s lifespan and quality of life.