What is Heart Disease in Dogs?
Heart diseases in dogs are any abnormality in the heart of a dog and its functioning. It comprises a wide range of conditions, can be congenital abnormalities (that is, gotten from birth) and disorders of physical structure, function, or electrical activity.
Statistics show that an estimated 7.8 million dogs in the United States have heart diseases, meaning that approximately 10% of all dogs in the United States have heart diseases.
Various factors are responsible for heart diseases in dogs, ranging from nutrition, ageing, breed, and obesity. Therefore, regardless of the cause of the heart disease your dog might have, you must spot the signs early; this way, you can best manage the condition if it develops.
Hence, let’s look at some signs that show your dog might have a heart problem.
Signs That Your Dog Has Heart Diseases
The signs of heart disease in your dog largely depend on the type of the disease and the severity of the disease itself. Most times, the symptoms may not start showing early, but then as the disease progresses, it could lead to congestive heart failure, in which case the heart would no longer be able to perform optimally and meet the pet body’s demand.
Other times, a pet may show signs of difficulty breathing, unwillingness to walk or exercise, a distended abdomen, trouble sleeping, or fatigue.
As mentioned above, there are numerous types of heart problems a dog can develop, but there are some of them which are most common among them.
When your dog develops a heart disease, it affects its body functions largely because the heart is a very important organ of the body. However, unlike in humans, the most common form of heart disease is valvular disease, which mostly affects small breed dogs and constitutes 70-75% of heart diseases in dogs. Also, heartworm disease causes 13% of heart disease.
Let’s now go through a few more common heart problems in dogs.
Common Heart Diseases in dogs
- Dilated Cardiomyopathy (DCM)
This is a family of diseases most common in dogs that weaken the heart muscle. This then leads to less blood being pumped out of the heart with each heartbeat, which causes the walls to stretch and the chambers to dilate or become larger, placing the dog at the risk of developing congestive heart failure (CHF).
Large and giant-breed dogs are more prone to being affected by DCM. Although, certain specific breeds of dogs have higher risks of developing DCM, among which are: Boxers, Great Danes, and Doberman Pinschers. DCM that is congenitally contracted is irreversible and progressive. The only remedy to this is early diagnosis and prompt medication.
- Valvular Degeneration
Your pet’s heart is anatomically similar to that of the human heart. It comprises four chambers, with two on each side, with valves that open and close to regulate blood flow. The valves are placed between the upper chamber (the atria) and lower chamber (that is, the ventricle) and at the exit from each lower chamber. However, as a pet age, their heart valves can deteriorate to the point where they no longer close totally, causing their blood to flow in the wrong direction. This is what constitutes valvular degeneration.
- Degenerative Mitral Valve Disease’ (DMVD)
The most common type of valvular degeneration is ‘degenerative mitral valve disease’ (DMVD). This disease occurs as dogs age when the mitral valve – the valve which separates the left atria from the left ventricle – thickens and becomes weaker; in effect, only a small amount of blood is allowed to flow backward through the valve with each heartbeat.
This backward flow is referred to as ‘mitral valve regurgitation. As the mitral valve regurgitation increases, there would be progressive heart enlargement, and the dog runs the risk of developing CHF. DMVD has been found to mostly affect older small-breed dogs, and although most dogs only experience mild disease, statistics show that 30% may experience more severe disease that would require lifelong management.
- Heartworm Disease
This is the only preventable heart disease affecting dogs. It is, however, potentially fatal. Heartworm disease is caused by an infection caused by a worm parasite, Dirofilaria immitis.
The organism is usually transmitted by mosquitoes carrying the heartworm larvae (known as microfilariae) from an infected animal host to a new animal host. The moment the larvae arrive in the new host, they grow into adult worms within several months and live in the blood vessels that serve the heart and the lungs.
The heartworms could enter the heart itself in more severe cases. Generally, small-breed dogs cannot withstand heartworm infections or treatments as well as large-breed dogs do. This is major because small-breed dogs have smaller blood vessels and heart chambers and can only tolerate fewer worms without vessel damage or blockage.
Fortunately, this disease is preventable, and it’s best to work towards preventing it than having to treat it in your pet. You can do this by keeping your pet on year-round heartworm preventatives and protecting your pet from developing heartworm disease. These medications can also prevent your family from contracting zoonotic infections.
In conclusion, asides from heartworm disease, most heart diseases that pets are prone to cannot be prevented; therefore, the best thing is for the disease to be discovered early to ensure that your dog has a long lifespan regardless of whatever heart condition he/she might have.