Five years ago this Thanksgiving my husband returned from North Carolina with our beloved Willie, an old-style red full standard Daschshund. My children swore they would forgo all other Christmas presents if they could have a dog. Bred back to “Tekkel” specifications with German stock, Willie is a barrel-chested 32 pounds. When his puppy rabies vaccination was expiring, I took him to one of the largest veterinary practices in the area. The examining vet said he was fine except for a heart murmur. I asked, “What can I do to help?” She replied, “Not much, really, just keep the dog fit and trim and never skip the heartworm medication. Make sure we see him promptly if he starts getting short of breath.” Despite this upsetting diagnosis, less than a year later we went back for Willie’s sister Schottzie, a black and tan Tekkel. Although the main goal in her life is to exceed her ideal 27 pounds by eating anything and everything, Schottzie has no signs of heart trouble, and Willie’s has not progressed.
Willie’s heart murmur is an early sign of myxomatous mitral valve disease (MMVD), the most common congenital heart disease in dogs. Also called endocardiosis, chronic degenerative valve disease, or chronic valvular fibrosis, MMVD accounts for 70% of canine heart disease. It is a genetic disorder which can progress to congestive heart failure and premature death. It starts with lesions that appear on the heart valve (usually the mitral valve), which eventually thicken and shorten the valve leaflets so they can’t close completely as the heart pumps blood through the chambers. MMVD is unlike atherosclerosis, the most common human cardiovascular disease, in which arteries become inflamed and trap cholesterol, blood clots, and/or proteins in a mass which eventually blocks an artery. Atherosclerosis is only partly genetic; its occurrence and severity is dependent on diet, lifestyle and environmental choices. The closest human analogy to MMVD is mitral valve prolapse.
Most of the breeds that have a high incidence of MMVD weigh on average less than 20 pounds. Some of these are listed in Table 1. The Cavalier King Charles Spaniel has the highest incidence of all breeds; in some Cavalier lines 90% of dogs will develop heart valve disease by age 10. Dachshunds are also very susceptible, particularly miniatures. On reason Willie has had no progression of his disease may be his large size. Another may be the exercise and nutrition program I developed for both dogs. Let’s examine both of these avenues.
Although definitive research has not yet been completed, several interesting genetic observations link MMVD to small weight dogs, especially toy and miniature breeds/forms. Here’s a brief summary of many studies:
- Since dogs are exceedingly inbred, congenital defects are common.
- All modern small dog breeds with a high incidence of MMVD share at least one common small dog ancestor that transmitted susceptibility genes.
- Constant breeder selection for small size also selected for some other genes that are detrimental. Unfortunately there was little choice in the matter because genetic information is “swapped” in discrete blocks, not by individual genes.
- Many genes that affect skeletal development also affect cardiac development.
- Fairly recently there has been a trend to miniaturize breeds. The heart does not reduce in size in proportion to body size reduction. Body size decreases faster, hence the chest cavity becomes too cramped for the heart, reducing its ability to expand and contract properly. This is especially a problem in small dogs that love to run hard, and for overweight dogs.
Running hard and tending towards overweight are describe my Dachsunds exactly. Both Willie and Schottzie get one to two hours of off-leash exercise daily, running, stalking jumping up on logs, digging etc. When it’s hot I take them in shallow water to walk by wading. I also taught them to jump off a pier and swim, and they have free run of the house and yard. To support this exercise they get only wet or homemade food, with plenty of fish, shellfish, eggs, venison, buffalo and beef. Vegetables and fruits of all sorts are chopped and added to each meal, but I do not feed them any grains. They receive glucosamine/chondroitin and Ark Naturals Royal Coat fish oil/borage oil blend three times per week. No sense waiting until the dog already has arthritis—it can be prevented or deferred.
The fish oil/borage oil blend is incredibly important. Although MMVD is not directly associated with inflammation of the arteries like human atherosclerosis is, the progression of the disease to congestive heart failure is associated with dramatic increases in biochemicals associated with inflammation. Part of the damage the lesions cause to the heart valves is inflammatory in nature, just like chronic knee or back pain. The surest, fastest and safest way to reverse any sort of chronic inflammation in cats and dogs, from heart disease to arthritis to dermatitis is fish oil/borage oil. Fish oil has the added benefit of protecting all mammals studied so far from other types of heart disease such as abnormal rhythms (atrial fibrillation). Together these oils will also heal itchy skin, flaky coat and restore a lustrous, full healthy coat.
As the dog ages he/she can be further protected from rapid progression of MMVD or other heart disease by using a supplement to strengthen the heart. When the valves leak, or the heart muscle becomes weak or damaged, the heart has to work harder to pump the same amount of blood. This can restrict exercise, which further weakens the heart and may cause the dog to gain weight, which again reduces mobility. A veterinarian will recommend that dog with congestive heart failure be exercise-restricted, but not an otherwise healthy dog with a heart murmur or slightly enlarged heart.
Ark Naturals Heart Healthy chewable supplement from the Gray Muzzle line provides three critical cardiac nutrients, taurine, carnitine and coenzyme Q10. When any of these are deficient the heart muscle runs out of energy. “Energy starvation” of the heart muscle is a primary feature of heart failure. Many research studies have shown that supplementation these nutrients for dogs, cats and humans with heart disorders is beneficial and safe. What makes Gray Muzzle Heart Healthy effective?
- Taurine is often called an amino acid but it is a sulfonic acid. It is critical for the maintenance and function of all muscles, particularly the heart. It is present in seafoods and meat, and can be synthesized by humans and dogs but not necessarily at optimum levels, especially to support a damaged or aging heart. Cats have a very high requirement for taurine but cannot synthesize it, so it must be in their diet or they will eventually perish
- L-carnitine is a non-protein amino acid that protects the heart muscle from oxidative stress and low oxygen levels due to poor circulation or partial arterial blockage. Like taurine, it is present in animal foods and can be synthesized, but not necessarily at optimum levels.
- Abnormally low levels of CoQ10 in heart tissue are observed in patients with heart failure. Supplementation reduces fatigue, improves exercise capacity, lowers blood pressure and increases the ability of the heart to pump blood.
- Adding the herb hawthorn to CoQ10 amplifies its ability.
- Botanical antioxidants such as bilberry, wheat grass, grape seed (and the produce I feed my dogs) and sulfur amino acids (egg protein is a rich source) are critical to prevent oxidative damage to the heart tissue and lower blood pressure.
- Diuretics such as dandelion slightly reduce blood volume, concentrating the oxygen-rich red cells and also reduce the fluid retention, which can occur if blood is not pumped through the kidneys at the optimal rate.
We all want to give every dog with a chronic heart condition every chance possible to delay or defer disease progression. With a little knowledge, there is so much you can do with good nutrition. Why not try? We’re always here to help with questions or comments.
Table 1. Selected dog breeds at increased risk for myxomatous mitral valve disease. The first list breeds have weights averaging 10 kg (22 pounds) or less. Dogs marked with* have large and small forms that are considered one breed but both sizes are affected.
Chihuahua Bolognese Maltese
Toy Poodle Pekingese Dachshund*
Miniature Pinscher Shih Tzu Miniature Schnauzer
Bichon Frise Pug Cavalier King Charles Spaniel
Miniature Poodle Whippet Papillion
Yorkshire Terrier Cairn Terrier Fox Terrier
West Highland Terrier Welsh Terrier Boston Terrier
American Cocker Spaniel Beagle Standard Poodle
Bull Terrier* Great Dane German Shepherd