Nutritional Supplements For Heart Disease In Dogs

Congestive heart failure or heart disease affects around one in three elderly dogs. The most common cause of heart disease is mitral valve insufficiency, where a 'leaky' valve on the left side of the heart allows blood to flow in the wrong direction during every heartbeat. This creates back pressure on the thin-walled left atrium, causing a series of hormonal and physical changes throughout the body which lead to fluid retention and further stress on the failing heart in a self-perpetuating vicious circle. Dogs with mitral insufficiency display signs of heart failure which commonly include poor exercise tolerance, coughing, and a swollen fluid-filled abdomen.

Dilated cardiomyopathy(DCM) affects large breed dogs, sometimes at a young age. This type of canine heart disease is characterised by thinning and weakening of the muscular walls of the dog's heart, often accompanied by an irregular heartbeat. Dogs with DCM may show similar signs to those with mitral valve disease, but also commonly show signs of weakness including fainting.

Before talking about any of the finer detail of nutritional deficiencies in dogs with heart failure, we must emphasise the importance of maintaining a healthy body weight in these pets. While low body weight in a patient with heart failure usually suggests a poor prognosis, obesity is a far more serious contributing factor to heart disease. The increased blood volume and heart rate, decreased exercise tolerance, and poor ability to regulate blood pressure in obese dogs greatly complicate successful management of their heart problems. It is vital therefore to aim for an ideal body weight in your pet with heart failure.

Every dog should be fed a good quality balanced diet to maintain a healthy body weight and general vitality. In addition, dogs with cardiac disease may benefit from supplementation with:

• Electrolytes & minerals (especially potassium and magnesium)
• Taurine
• L-carnitine
• Omega-3 fatty acids
• Vitamin E
• Selenium

Electrolytes and minerals such as potassium and magnesium play an important role in allowing the cardiac muscle to contract normally (as in the video clip above). Deficiencies in these nutrients will cause heart muscle weakness and a worsening of the signs of heart failure in dogs. Unfortunately, it is not easy for your veterinarian to determine whether deficiencies exist, as these minerals are stored in body tissues rather than in the blood, meaning that it would require a biopsy of your dog's heart muscle to measure the true state of affairs.

It is advisable therefore to provide supplemental potassium and magnesium (within safe limits) to your dog with heart disease. Overloading him with potassium in particular is not advisable, but any reputable mineral supplement for dogs will not exceed safe levels.

Although taurine deficiency is well-established as the most common cause of DCM in cats, its role in dogs is less clear. However, most veterinarians would advise supplementing the diet of any dog with a failing heart with this amino acid which is normally found in meat.

L-carnitine is a fat-soluble vitamin which plays a pivotal role in heart function. It is found in high concentrations in healthy heart and skeletal muscle. Fatty acid breakdown is the main source of the energy which drives the contraction of your dog's heart, and it is L-carnitine which allows these fatty acids to be metabolised. L-carnitine deficiency is the cause of dilated cardiomyopathy in a proportion of dogs, and supplementation may be helpful in maintaining muscle mass while controlling obesity in many older dogs.

As it has the potential to have a massive positive impact on some cases of canine heart disease, it should be supplemented in all dogs with heart failure.

By definition, a heart that is failing is unable to meet the body's demands despite working at maximum capacity. The stress that this effort places on the heart leads to further damage, inflammation and scarring in the walls of your dog's heart and contributes to deteriorating heart function over time. Anti-oxidants such as omega 3 normally found in fish oil, have been shown to reduce the risk of sudden death and severe cardiac rhythm disturbances in dogs with heart disease.

Omega 3 fatty acids such as linolenic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) have a range of other beneficial effects in dogs including improved function of the nervous system and kidneys.

Likewise, vitamin E and selenium work together to reduce stress on the dog's heart muscle and reduce the development of stress and scarring.