General Issues in Feeding Dogs with Cardiac Disease

5. General Issues in Feeding Dogs with Cardiac Disease

Dietary modification in dogs needs to be individualized - not all dogs with cardiac disease will need the same dietary formulation. Patients with cardiac disease vary in terms of their clinical signs, laboratory parameters, and food preferences and these should all affect diet selection. For example, more severe sodium restriction would be required for a dog with DCM and CHF than for a dog with asymptomatic DCM. Dogs with cardiac cachexia require a calorically-dense diet while an overweight dog should be fed a calorically-restricted diet. Dogs with cardiac disease may be hyper-, hypo-, or normokalemic and this will influence the choice of diet.

Concurrent diseases also influence diet choice and, in one study, concurrent diseases were present in 61% of dogs with cardiac disease (Freeman et al., 2003b). For example, a dog with CVD and colitis would need a diet that is sodium restricted but also one that has nutritional modifications to help manage the colitis (e.g., reduced fat, increased fiber).

Based on these patient parameters, a diet or diets can be selected for the individual patient. There currently are a number of commercial veterinary diets available that are specifically designed for animals with cardiac disease. Specific characteristics of these foods vary, but they are moderately to severely sodium restricted and generally contain increased levels of B vitamins. Some cardiac diets also may include increased levels of taurine, carnitine, antioxidants, or n-3 fatty acids. In some cases, a "cardiac" diet may not be needed as some over-the-counter diets may have the properties desired for an individual dog. The authors also recommend offering more than one diet that would be appropriate for a dog so that the owner can see which is most palatable to the pet. Having a number of dietary choices is particularly beneficial for more severely affected CHF patients, in which a cyclical or selective loss of appetite is common.

In addition to the dog food(s) selected, one must also give the owner careful instructions on treats and table food. In some cases, dogs may be eating an ideal dog food but are getting large amounts of sodium from treats. In one study, over 90% of dogs with cardiac disease received treats and these dogs were receiving up to 100% of their sodium (median, 25%) from treats (Freeman et al., 2003b).

Therefore, in addition to finding a diet that has the desired nutritional properties and palatability, it also is important to devise an overall dietary plan that meets the owner's expectations. This includes devising a satisfactory method for administering medications. Most people administering medications to their dogs use foods as a way to administer the medication (Freeman et al., 2003b). Discussing appropriate options for an owner to use for this purpose is necessary, as the foods most commonly used by owners are very high in sodium (e.g., cheese, lunch meats, etc.). Including all forms of dietary intake in the overall diet plan is important to achieve success with nutritional modification.

In many cases, the desired nutrient modifications can be achieved through diet alone. However, supplementation of certain nutrients may be desirable if they are either not in a particular diet or not at high enough levels to achieve the desired effect. One issue with the administration of dietary supplements is that they should not take the place of standard cardiac medications (e.g., ACE inhibitors, diuretics). Dogs with severe CHF may be receiving 10 - 20 pills per day and it may be difficult for the owner to give supplements on top of this without discontinuing one or more of the cardiac medications. It is important to ask each owner about any dietary supplements being used as this is often not information that is volunteered (i.e., dietary supplements are often not considered medications or diet). This will help to determine if any harmful supplements are being given and if the supplements are being given at an appropriate dose. In situations in which pill administration is becoming overwhelming for an owner, the veterinarian can assist the owner in determining which dietary supplements have the least potential benefits and can be discontinued.

There currently are a number of commercial veterinary diets available that are specifically designed for animals with cardiac disease. Specific characteristics of these foods vary, but they are moderately to severely sodium restricted and generally contain increased levels of B vitamins. Some cardiac diets also may include increased levels of taurine, carnitine, antioxidants, or n-3 fatty acids.

Finally, owners should be aware that dietary supplements are not regulated in the same way as drugs. They do not require proof of safety, efficacy, or quality control before they can be sold. Therefore, careful selection of type, dose, and brand is important to avoid toxicities or complete lack of efficacy.