Heart Disease in Dogs (CHF in Dogs)
What is Heart Attack?
A heart attack, or “myocardial infarction,” happens when blood is blocked from reaching the heart muscle (myocardium). Deprived of oxygen and nutrients, the heart muscle dies and the affected heart chamber can no longer effectively pump blood through the body. Canine heart attacks have been seen in all breeds and are very rare. Increased risk for heart attack can be seen accompanying heart disease, congenital heart abnormalities, and genetic predisposition. Heart attacks require emergency medical attention and can result in sudden death. Canine heart attacks have been seen in all breeds and are very rare. If you notice symptoms of a heart attack in your dog, keep calm and contact a veterinarian immediately.
Types of heart disease
The heart is an important and complex organ, and heart disease in dogs can show up in a variety of ways affecting specific parts of the heart and body.
The heart is divided into different parts to pump blood throughout the body. The right side, made up of the right atrium and ventricle, directs blood to the lungs so that the blood cells can pick up oxygen, which is then delivered back to the heart. Then the left side, which contains the left atrium and ventricle, pumps the newly oxygenated blood throughout the rest of the body through the circulatory system.
Just like with heart disease in humans, when heart disease develops in a dog, their heart must adapt or change in order to continue to work efficiently and bring oxygen to the rest of the body. These changes typically occur slowly over time—often years—and cause enlargement of the heart. This timeframe is known as the preclinical form of heart disease, considered as such since dogs show no obvious outward signs of heart disease.
Heart disease is an unfortunate but tolerable condition for your dog. The heart is the most important organ in your dog’s body. It pumps blood containing oxygen and nutrients through the blood vessels to the cells of the body. Most heart conditions involve a decrease in the effective pumping of blood. This can lead to a buildup of fluid in the chest and abdomen. There are two main types of heart conditions: one affecting the heart valve and the other the heart muscle. Dogs with either type can be successfully managed through nutrition, exercise and, if necessary, medication. With the right dog food and advice from your veterinarian, your dog can continue to enjoy a happy, active life.
The two main heart conditions
Chronic Valvular Disease: A leaking heart valve reduces the quantity of blood that can be pumped around the body.
Myocardial Disease: In this condition, weakness or thickening of the heart muscle results in the heart pumping less efficiently.
What causes heart disease?
Although there is no single cause, nutritional problems can play a major role in heart conditions. Aging is the most common reason dogs develop heart conditions, but other factors like heartworm can also lead to heart disease. Other factors that can contribute include:
Body condition: Overweight dogs are more likely to develop heart disease.
Age: Heart conditions in dogs occur more frequently with increasing age.
Breed: In dogs, chronic valvular disease is more common in small breeds such as miniature poodles, cocker spaniels, Pomeranians and schnauzers. Myocardial disease is more common in large and giant breeds like Great Danes and Irish wolfhounds.
Heart disease is a relatively common problem in dogs, especially for certain pedigrees such as the Cavalier King Charles Spaniel (prone to mitral valve disease), and the Doberman (prone to dilated cardiomyopathy).
Some of the most common types of heart disease in dogs include:
Mitral valve disease is a problem with a one of the valves inside the heart. It’s particularly common in small breeds such as the Cavalier King Charles Spaniel, Dachshund, and certain terriers.
Dilated Cardiomyopathy is a weakness in the heart muscle that causes the heart to become large, floppy and unable to pump blood properly. DCM is most common in large/giant breed dogs such as the Doberman and Great Dane.
Arrhythmias
An arrhythmia is an abnormal heart beat rhythm that can cause fainting episodes.
Congenital heart disease
A congenital problem is something a puppy is born with. Congenital heart disease is usually quite serious, but fortunately, it’s also rare. There are many different types of congenital heart disease, including:
- Patent ductus arteriosus (PDA)
- Pulmonic stenosis
- Aortic stenosis
- Atrial septal defects (ASD)
- Ventricular septal defects (VSD)
- Tetrology of Fallot
Pericardial disease
The pericardium is a thin membrane that sits around the heart, so pericardial disease is anything that goes wrong with this membrane.
Symptoms
Heart problems tend to cause symptoms such as:
- Coughing
- Breathlessness, heavy breathing or excessive panting
- Lethargy (low energy)
- Exercise intolerance (slowing down on walks)
- A heart murmur (which will be heard by your vet)
- Collapse/fainting
- Weight loss
- Abdominal swelling
The following symptoms may indicate a heart problem in your dog.
- Tired, lack of energy
- Fainting or collapsing
- Frequent coughing. In some cases, a low-pitched cough that sometimes leads to gagging
- Breathing difficulties that include shortness of breath
- Reduced ability to exercise
- Reduced appetite and/or noticeable weight gain or loss
- Swelling in the abdomen
IMPORTANT: A heart condition may not be obvious in the early stages. If you are in any doubt about your dog’s health, consult your veterinarian.
Treatment: The importance of nutrition
Although treatments cannot reverse heart disease, your dog can live a relatively normal life. The food your dog eats plays an important role in his overall health and well-being. When your dog has been diagnosed with a heart condition, it’s even more important to feed the right dog food.
Heart disease typically causes the heart to enlarge, and this enlargement causes a loss of efficiency. The heart then begins to hold more fluid than it should and this is where the real problems begin. For this reason, veterinarians recommend feeding dogs a low-sodium food that will help reduce fluid build-up and make it easier for their hearts to work effectively.
For accurate diagnosis and treatment options, always consult your veterinarian and ask them to recommend the best food for your dog’s heart health.
The treatment your dog needs will depend entirely on the type of heart problem they have. Follow the links above for more information about treating a specific type of heart disease. However, common treatments include:
- Monitoring. Some heart conditions don’t need treatment in the early stages. However, if this is the case, it’s likely that your vet will ask you to monitor your dog and return for regular check-ups.
- Medication. Most common types of heart disease can be managed with medicines, careful monitoring and lifestyle changes. Heart medications may not cure your dog’s problem, but may slow its progression down and reduce symptoms. It’s important to be aware that even with medication, most types of heart disease get progressively worse with time.
- Surgery. There are certain types of heart disease (mostly rare, congenital problems) that can be treated with an operation. Surgery can be very successful, but is only useful for specific types of heart disease. It’s important to know that heart surgery has significant risks, can be expensive and is usually only performed in a specialist veterinary centre.
FAQ ON HEART DOGS
What are the signs of heart disease in dogs?
The clinical signs of heart disease depend on the type of disease and severity. It is important to note that early on there may be no symptoms at all. As heart disease progresses to congestive heart failure, which occurs when the heart is unable to meet the body’s demands, a dog may develop more obvious symptoms such as fatigue, reduced willingness to walk or exercise, difficulty breathing, loss of appetite, weight loss, a distended abdomen, trouble sleeping or coughing. If you see any of these symptoms, you should have your pet seen by a veterinarian immediately.
How do you know if your dog has heart disease?
Since early heart disease is asymptomatic, it is best to take your dog to the veterinarian every year to screen for heart disease. Your veterinarian will listen to your pet’s heart for abnormal sounds like murmurs or irregular rhythms and will look for other subtle signs of heart disease. If your veterinarian suspects heart disease, they may measure blood pressure or suggest additional tests like x-rays, cardiac ultrasounds, or ECGs to confirm the diagnosis and determine the cause so that treatment can be started.
What can you do if your dog develops heart failure?
While there is no cure for congestive heart failure (CHF), fortunately there are medications available to help the heart work better. The Quality of Life and Extension of Survival Time trial (QUEST), the largest clinical trial studying of dogs with CHF, reported that dogs treated with pimobendan lived longer and enjoyed a higher quality of life compared to dogs treated with conventional therapy. Speak with your veterinarian or a veterinary cardiologist to determine which medications your dog will need depending on the type and severity of their heart disease.
What can you do to prevent heart disease in dogs?
Unfortunately, although diet and exercise are important for preventing other important diseases like obesity, diabetes and arthritis, they have not been found to prevent acquired heart disease in dogs. In fact, most forms of heart disease in dogs cannot be prevented except for one notable exception: heartworm disease. It is sad to think that 13% of all dogs in the US with heart disease have a disease that is entirely preventable. Keeping your pet on year-round heartworm preventatives can protect your pet from getting this deadly disease. Although heartworm disease can be treated, it is much easier to prevent it in the first place. In addition to preventing heartworm disease, these medications are also effective against other internal parasites and can protect your human family from zoonotic infections. Protecting your pet from heartworm disease not only makes sense, it’s also really simple!
Although heart disease in dogs cannot be prevented with the exception of heartworm disease, the goal is early diagnosis and treatment. Routine visits to the veterinarian can help catch heart disease while it is still asymptomatic. During these visits, your veterinarian will listen to your dog’s heart for murmurs or irregular rhythms and look for early signs of heart disease. Additional tests like x-rays, cardiac ultrasounds or ECGs may be ordered by your veterinarian to establish the diagnosis and determine the cause in order to start the right treatment. Starting treatment earlier can improve quality of life and extend life expectancy.
Take home message:
The take home message is that heart disease is almost as common in dogs as in people. Even though most forms cannot be prevented, heart disease caused by heartworms can easily be avoided with year-round preventatives. Likewise, in dogs who have developed heart failure, quality of life and life expectancy can be improved with early diagnosis and treatment. I recommend taking your dog to your veterinarian for a routine check-up to screen for heart disease at least annually and every 6 months for older pets.
If you have any questions or concerns, you should always visit or call your veterinarian – they are your best resource to ensure the health and well-being of your pets.
Compiled & Shared by- Team, LITD (Livestock Institute of Training & Development)
Image-Courtesy-Google
Reference-On Request.
