The pathology of an older dog is dominated by cardio-pulmonary affections. As a dog gets older, it may begin to cough, breathe with difficulty and get tired even after taking shorts walks. These are signs that might not seem very important at first, but which can hide a congestive heart failure. The body of a dog is no longer as strong as it once was. You have probably noticed that your dog fails to catch up like it used to. Aging may predispose any canine specimen to the development of certain diseases.
As a dog owner, what you can do is to educate yourself in order to be a better protector for your pooch.
In fact, heart failure represents the myocardial inability to adapt to effort or to other common body needs. In these conditions, the cardiac output decreases and the tissues no longer receive a sufficient amount of oxygen. Coughing and difficulty in breathing are 2 of the most popular signs that predict the occurrence of heart failure in dogs, but the passive congestion of their organs can also be present. The congestive aspect intervenes when a dog’s heart fails at pumping blood at the needed rate in order to meet the basic needs of its body.
Although this disease is not curable, there are treatment options that can improve the quality of your dog’s life.
Particularities of congestive heart problems
As this disease progresses, the regurgitation of blood from the ventricles back to the atria determines the occurrence of an increased blood volume and blood pressure in both chambers of the heart. In the mitral valve, the increased blood volume could affect the lungs. This is because the water from blood will enter the lungs, causing pulmonary edema and then heart attack.
Conversely, in the tricuspid valve, the increased blood pressure allows blood to go directly in the chest and in the thoracic cavity. A heart disease in dogs should be taken as serious as it is taken in case of humans. The changes that take place can definitively affect a pooch’s life and even lead to its death before you know it.
In general, the congestive heart problems start appearing in dogs that are older than a decade. When their heart fails at keeping up with their bodies’ needs, the increased pressure from their pulmonary circulatory system determines the water from their blood to flow directly into their lungs.
The accumulation of water causes coughing. At times, this cough becomes excessive and it requires medication. However, you should not administer any kind of medication to your pooch before you take it to the vet. Establishing a correct diagnosis is not easy for a vet either and it would probably ask for a lot of tests, so this is definitely not something you can do at home.
Multiple causes of congestive heart problems
In this case, the etiopathogeny is multiple and complex. In simpler words, the causes and the development of this heart disease may be mechanical and biomechanical. Arrhythmias reduce the cardiac output and the ineffective contractions, while the direct mechanical compressions determine the installation of heart failure. For example, worms can cause congestive heart problems or they can simply be hereditary, especially in case of Boxers.
In other cases, a weak heart muscle is enough to cause the occurrence of this heart problem. The factors that determine it are various and more or less threatening depending on their nature and severity.
Heartworm in dogs is caused by a filarial parasite called Dirofilaria Imitis. This disease has been reported in most countries with subtropical, tropical or temperate climates. Dirofilaria is refered to as heart worm because that is where it is found in dogs. The presence of this parasite in a dog’s heart or blood vessels weakens its cardiovascular system, causing pulmonary impairment and, ultimately, death.
At least 70 species of mosquitoes can serve as intermediate hosts for this parasite. Among the most popular species are Aedes, Anopheles and Culex. The disease can occur in many species of wild and domestic animals, such as wolves, coyotes, foxes, raccoons, dogs, and less commonly in cats and ferrets. Although any dog is susceptible to infection if it is kept outside or inside the house, most infections are diagnosed in dogs aged between 3 and 8 years old.
Man is also susceptible to infection with Dirofilaria from mosquito bites, but this disease does not manifest itself so seriously as in case of animals.
A possible deficiency of vitamin E and selenium also favors the occurrence of myocardial dystrophy. It can be said that the lack of something that sustains the energy needs of a dog can have severe consequences. Cases when a dog starves or it has to do intense exercising are perfect examples in this regard. Stress, poisoning and the lack of vitamins consume all the energy left in a dog before it begins to show signs of illness.
Moreover, heart failure can be primary or secondary to other diseases, such as atherosclerosis, chronic nephritis, liver disease or obesity. Heart failure is compensated when the clinical signs manifest after a session of intense effort and uncompensated when these are obvious at all times or even worsen during rest periods.
Heart failure involves increased levels of venous pressure that acts against the affected ventricle, but it also involves lower levels of blood pressure. In congestive heart failure cases that develop slowly, the collapse of blood pressure and the installation of cardiogenic shock are 2 of the most probable outcomes.
A dog’s myocardium tries and succeeds to adapt to the new situation by using different compensation mechanisms, such as tachycardia, tachypnea that means rapid contractions of the heart, vasoconstriction and by increasing its volume. After a while, the poor irrigation of the internal organs causes pulmonary edema, liver failure and passive venal congestion.
The peripheral cardiac edema appears when sodium and water retention are caused by different types of renal insufficiency. The evolution of this cardiac affection along with others is gradual. More specifically, at the beginning a normal type of physical activity does not cause fatigue, shortness of breath or cough. However, as the disease becomes chronic, these signs occur at rest and during exercise.
Congestive heart failure is the type of disease that becomes chronic and manifests by changes like a dog’s heart appears larger in volume because of dilation or hypertrophy, its sounds are diminished and its jugular vein is turgid.
Symptoms that may occur in case of heart disease
The symptoms of congestive heart failure in dogs appear most often in case of small sized dogs that are males. Both sexes may suffer from this disease, but somehow males are affected in a larger number. The dog breeds that have shown signs of predisposition to heart diseases like this one are Poodle, Cocker Spaniel, Schnauzer, Dachshunds, Terriers, Cavalier King Charles Spaniel and so on.
The latter dog breed is more sensitive than the others and it can become ill at a much younger age compared to its fellow canine friends. However, many specimens manage stay healthy throughout their lives. Large breeds of dogs such as German Shepherd, Doberman or Weimeraner can also be affected by heart problems, but such cases were not met often.
At the beginning, except for the murmur of the heart, there are no other symptoms. Only a veterinarian can identify the installation of a heart disease during a routine medical control. As the congestive heart failure progresses, some of the most common symptoms are cough, dyspnea, and accelerated breathing.
Other symptoms that may appear on the way are depression, lack of appetite and weight loss. In addition, fainting and arrhythmias may occur in some severe cases. Moreover, every organ from a dog’s body might be affected by congestive heart failure. Common signs include weakness, lethargy, enlarged liver and abdominal distension. Signs such as jugular vein distension and heart murmur can only be observed by a specialist after it examines the sick pooch.
Establishing a diagnosis by the vet
It goes without saying that the vet is the only entitled person who can establish a diagnosis for your dog. He or she will have to differentiate between the causes of heart failure when examining your dog. Most probably he or she will recommend for a complete blood profile to be conducted, including a chemical blood profile and a complete blood count. He or she might also request a urinalysis, along with a heartworm testing.
In addition, you will be responsible with providing a complete history of your dog’s health, symptoms, and possible incidents that may have preceded this condition.
The information provided by you can give important clues to the veterinarian. If there is any information you can give about your dog’s family line too, that would help the doctor identify the origin of the heart disease. If the tests mentioned above are not enough to draw a conclusion, the vet will require a chest radiograph, a cardiac and an abdominal ultrasound, EKG and a blood pressure measurement.
Possible treatments for chronic heart failure
In most cases, the treatment for congestive heart failure and other types of heart failure is directed toward relieving its symptoms and it may involve the usage of the following drugs: diuretics, ACE, digoxin and others. These drugs are meant to improve a dog’s cardiac tone, stimulate diuresis, combat arrhythmias and treat related diseases.
When ascites or the accumulation of fluid in the chest cavity is involved, then surgical intervention is required in order to remove the liquid. Diuretics might help sometimes, but it really depends on the seriousness of the accumulation and on how complicated is the heart disease.
The degenerative affection of the heart’s valve is the most common cause of heart disease that appears in small sized dog breeds and in dogs older than a decade. Treatment is always aimed at relieving the symptoms and it is rarely curative. However, every prescription must be individualized because every dog is different and reacts different to treatment.
Among the most obvious recommendations is less physical activity, less salt in food and less stress or agitation. Of course, those canine specimens affected by a serious stage of heart failure will be subjected to more aggressive solutions that might improve their health.
Spironolactone blocks the action of a hormone called aldosterone at kidneys, heart and blood vessels levels. By blocking aldosterone, spironolactone causes the elimination of salts and fluids with the help of a dog’s kidneys, but it somehow manages to retain potassium, thereby improving heart function. It is recognized that there are other ways in which spironolactone works on the heart and blood vessels in case of congestive heart failure, but these mechanisms of action are not fully demonstrated in dogs.
Results of the studies showed that dogs with congestive heart failure caused by the malfunction of the heart valves that received this treatment along with the standard treatment had a higher rate of survival than dogs that received the standard therapy plus placebo tablets. In a long term study, it was also shown that dogs that were treated with spironolactone had a lower rate of heart disease worsening compared with dogs that only received the standard treatment.
The treatment with this drug was generally well tolerated when administered daily to dogs with heart diseases for up to 15 months. Since spironolactone can reduce the value of certain male hormones, male dogs which have not been neutered may show signs of prostate reduction. However, this effect is reversible. For the same reasons, spironolactone should not be administered to canine specimens that are still in the growth phase.
In addition, it should also not be administered to dogs that have high blood potassium levels, also called hyperkalemia, or a low level in serum potassium, also called hypokalemia, or to dogs that experience a reduction in the corticosteroid secretion from the adrenal gland. Spironolactone should not be administered to dogs with kidney disease that receive drugs known as NSAIDs, which stands for nonsteroidal anti-inflammatory drugs. As spironolactone is converted to the liver, these tablets should be administered with caution in dogs with liver disease.
Preventing heart problems from occurring
The prevention of congestive heart failure depends on what might cause it in the first place. For example, if worms are those determining the heart disease, then, as a dog owner, you should always make sure your dog is on the right meds that prevent worms from getting through. Whenever you visit the vet, you should ask about those as well. He or she might know what to do, but sometimes aspects like these might slip his or her mind. Asking every time or multiple times is never going to be a problem, but not asking at all might be.
What you feed your dog is of great importance in this case too. You should choose a rational nutritional plan that fits your dog’s age and level of activity. Moreover, you should consider its general health state when you choose one. Dog food should be easy to digest, low in sodium and rich in vitamins. As a loving owner of a dog, you can go for special food made for dogs with heart diseases or for those that are prone to developing one. Specialists have concluded that L-carnitine and coenzyme Q10 are important in the process of myocardial energy production.
Importance of targeted treatment
The treatment available for all kinds of heart diseases that manifest in case of dogs is general and it is addressed to the entire symptomatic procession related to these conditions. The improvements of the heart function, as well the administration of diuretics are 2 of the main steps that are usually recommended.
After interpreting all the test results, a vet will try to determine the cause that contributed to the installation of the heart affection in case of a specific dog. This is because the cause is never the same for all dogs. In most cases, there is a complex chronic pathology related to other organs and systems that might have triggered the heart failure.
An essential goal in this situation is to assess the patient’s chances of responding to a specific treatment. Individual peculiarities are extremely important and should be seriously taken into account during investigations and for establishing a treatment.
Your pooch’s body is a complex machine that functions based on multiple fuels. Once something goes wrong inside it, that thing triggers the deregulation of other systems, fact which leads to a very unpleasant situation when you might not know what to do and the vet might not have a definitive answer for you.
Just as our human loved ones get sick and need care, so do several canine specimens. Heart failure is among the most inconvenient affections, but depending on its evolution stage it can be managed or not. Most often it is manageable and can ensure a few more years of happy life for your pooch.