How diet helps with heart failure in small breed dogs

woman and dog

Do you have a small breed dog? You might want to pay attention to this article about heart health.

Myxomatous mitral valve disease also known as MMVD accounts for approximately 70% of all canine heart disease cases and heart failure. The disease is especially prevalent in small-breed dogs.

Treatment historically called for feeding dogs that suffered from MMVD a low-sodium diet (just like in humans), however recent research has shown that there are other nutrients that are equally important to the continued heart health in dogs. Continue reading to learn what those nutrients are.

woman and dog

What is MMVD?

Myxomatous mitral valve disease (MMVD) is by far the most commonly diagnosed cardiovascular disease in dogs. It is most likely congenital and passed on genetically and many of the breeds affected are small or toy breeds that have an average weight of under 18 lb.

It is particularly prevalent in specific breeds like the Cavalier King Charles Spaniel, with approximately 90% developing MMVD by 10 years of age.

Another breed that acquires the disease quite commonly are dachshunds.

It is a chronic condition that can progress quickly depending on the stage. Dogs that have the disease usually do not develop clinical signs of congestive heart failure (CHF) but some signs can be:

Signs of MMVD include:

  • heart murmur (usually develops after 6 years of age)
  • heart failure
  • mitral valve thickening or MVP

What nutrients should I include in my dog’s meals?

1. Omega-3 fatty acids

Omega-3 fatty acids provide anti-inflammatory and antithrombotic benefits. The long-chain EPA (eicosapentaenoic aid) and DHA (docosahexaenoic acid) both help to reduce inflammation associated with heart failure.

Along with their anti-inflammatories effects they have antiarrhythmic, antithrombotic, and hypotensive effects

In one study, supplementing with these unsaturated fatty acids or (PUFs) reduced atrial fibrillation in Boxers.

2. Medium-Chain Triglycerids

Medium-Chain Triglycerides or MCT’s are derived from coconut or palm oil, or milk fat and have been shown to provide an alternative energy source for cardiac mitochondria and help reduce free radical production.

When compared to Long-chain fatty acids (LCFAs) like those mentioned above medium-chain fatty acids (MCFAs) are more easily digested, absorbed, and oxidized. In fact, one study showed that cardiac mitochondria became less efficient at using LCFAs as an energy source when compared to MCFAs.

In various instances, MCTs were shown to improve cardiac function.

3. Magnesium

Magnesium supports normal cardiac rhythm because it is a cofactor in a lot of enzymes including those that keep the heart pumping. It can also help reduce blood pressure by enhancing vasodilation, it is required for normal cardiac function.

It is heart protective against inflammation and reduces oxidative stress and in human medicine, it was shown that an increase in serum magnesium was associated with a lower risk of cardiovascular disease.

A decrease in magnesium or hypomagnesemia is associated with an increase in inflammatory markers in humans.

In rats, supplementation with magnesium was shown to reduce oxidative stress, reduced hyperlipidemia, and enhance cardiac function.

While there needs to be more experiments done for dogs on the effects of magnesium and the heart one study showed that it can help in cases of ventricular arrhythmias. There are currently no studies that have targeted MMVD dogs specifically.

4. Antioxidants

Your dog’s diet should include antioxidants that can counteract oxidative stress. Other antioxidants to include are

  • Taurine -a sulfur-containing beta-amino acid that counteracts oxidative stress, however, most dogs produce enough to be sufficient in maintaining heart health and do not need to be supplemented.
  • Vitamin E
  • Methionine – Important for carnitine production
  • Lysine – Important for carnitine production
  • Carnitine – A compound that dogs can get through their diet or endogenously from the amino acids methionine and lysine. There has also been a link between DCM in dogs and low myocardial carnitine (read more about that here).

Dietary supplementation of antioxidants can include the vitamins themselves but in many cases, like that of carnitine, it is better to give the precursors to support the body in making the final product. Such is usually the case for carnitine, owners can give vitamins that include methionine and lysine which are its building blocks.

The Study

The study referenced here showed that a complete and balanced diet that contain all of the nutrients and vitamins mentioned in the post had positive effects on dogs with MMVD.

The results showed an improvement in 30% of the dogs given the nutrients and no improvement in the control dogs not given the nutrients. Several of the control dogs progressed from stage B1 to B2 but none of the MMVD dogs fed the nutrient blend progressed to stage B2.

Data from the study suggest that there are key nutrients that can positively affect MMVD dogs and should be studied further.

When discussing these nutrients with your vet, keep in mind that many more studies need to be done, many of these supplements have been tested on humans or rats and not dogs, and supportive evidence specifically in dogs is lacking for some. 


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6. VIN