The heart is a very important organ in the body, whether human or canine. Canine heart disease is usually a progressive condition that takes years to develop, as the dog ages and heart muscles or valves get worn out. In most cases, symptoms do not immediately occur or manifest very subtly.
As such, even though timely diagnosis is important to allow early treatment of the disease, dog heart problems frequently go unnoticed until they are at the advanced stages and clinical signs are apparent. Having pet owners knowledgeable about common signs of heart disease in dogs can be beneficial in helping them spot out potential problems early on.
This article thus serves as a guide for dog owners for telltale signs to watch out for that may suggest heart problems. Of course, these clinical signs may also be observed in other health conditions that may not be directly related to the heart. Therefore, it is best to visit your veterinarian for regular health check-ups so that they can accurately find out if anything is bothering your fur baby.
Exercise Intolerance
Heart disease impedes the heart’s ability to pump blood that delivers oxygen throughout the body. As such, a decrease in stamina can be observed in dogs with heart problems. You may find your pooch easily out of breath after a short burst of physical activity such as during exercise. They may appear to have some trouble catching their breath and may easily get tired from walking and playing.
Weakness and Tiredness
Because they easily run out of breath after doing physical activities, dogs with heart problems get easily tired and fatigue faster than healthy dogs. You may find an otherwise active pooch to lie down more frequently and sleep longer than usual. They may appear to lack energy and are less inclined to move around, play, or take long walks. This generalized weakness may be accompanied by depression, as your pooch may appear to have lost their joy in life.
Fainting Episodes
When the blood pressure is too low and the heart fails to deliver enough oxygen to the brain, a dog may faint or collapse, losing consciousness temporarily. The medical term for this occurrence is syncope, and it may be triggered following exercise or strenuous physical activity, when the heart is challenged to pump more blood to various organs of the body. Watching your dog faint can be very alarming and scary. Dogs usually recover spontaneously from a fainting episode as if nothing happened once enough oxygen has been delivered to the brain. However, it is best to keep calm, alert, and bring your dog immediately to the vet once you notice your pooch has fainted.
Respiratory Problems
Dogs with heart problems typically show abnormal respiratory symptoms associated with difficulty in breathing or being dyspneic, such as breathing too heavily, taking quick shallow breaths, or even having difficulty breathing in certain positions, such as when lying down. Additionally, dogs with heart disease may develop a persistent cough that does not resolve after days, weeks, even months.
In most conditions related to heart muscle problems and valvular disease, fluid builds up in the heart due to poor pumping, causing the heart to enlarge. The enlarged organ can press on nearby anatomical structures such as the airways, causing your dog to cough. Additionally, as the blood overflows in the heart chambers, fluid can spill over the lungs, causing pulmonary edema. This can be another cause for the persistent cough seen in dogs with heart disease.
Cold and Blue
Another problem with poor delivery of oxygenated blood to the different organs of the body due to heart disease is that distal body parts such as the ears, paws, and tail may appear cyanotic or blue and cold to touch. The skin and mucous membrane, such as the gums, can also appear bluish. Cyanosis and cold extremities usually suggest an emergency, as the dog must be immediately attended to with critical care in order to improve and stabilize the oxygen levels in the body.
Enlarged Tummy and Extremities
An enlarged abdomen, the medical term for which is ascites, is due to the buildup of fluid within the abdominal cavity. Dogs with an enlarged tummy due to fluid buildup develop a bloated or pot-bellied appearance. Following heart disease, ascites can occur, as well as swelling of the distal extremities such as the legs.
These types of clinical signs are usually associated with right-sided heart failure that leads to portal hypertension, or the increased pressure in the portal blood vessel that delivers blood from various internal organs to the liver. Because of portal hypertension, plasma proteins escape from the capillaries into the interstitial space. The fluid and osmolar imbalance causes fluid and proteins to escape into the abdominal circulation, leaving less volume available for circulation throughout the body.
Ascites is one of the reasons why vets prescribe diuretics and a low sodium diet to dogs with heart failure. Diuretics will help the dog excrete the excess fluid in their body, and a low sodium diet will prevent fluid retention. Concurrently, dogs are also given medications that will help improve cardiac function.
Reduced Appetite and Weight Loss
As having heart problems bring about some difficulty and general feeling of discomfort for your dog, as seen especially from the clinical signs listed above, it is only inevitable that they gradually lose appetite for food and feel less inclined to eat over time.
Following reduced appetite, dogs may naturally lose weight. However, some dogs with heart disease may still eat normally yet lose so much weight at an alarming rate, and this phenomenon is called cardiac cachexia. Cardiac cachexia is common in dogs with congestive heart failure. It leads to loss of lean body mass that ultimately causes general weakness and lethargy.
Many factors, and not just a reduced appetite, contribute to cardiac cachexia. Because of the underlying heart disease, the animal’s body demands an increase in nutrients and energy. However, nutrient absorption and metabolism are impaired, and the body may be too busy producing inflammatory cytokines that can also harm the body because is not getting enough glucose, it turns to protein for energy, leading to muscle wasting.
Following diagnosis of heart disease, your veterinarian will recommend dietary changes to help your dog with weight management and to meet their optimum energy requirements. Proper diet is just as important as medications in managing canine heart problems and ensuring that your pooch can still live the rest of their life comfortably.