The heart is one of the most important organs in a dog’s body. It ensures oxygen in the blood reaches all areas of the body. When it doesn’t pump efficiently, other organs are affected. The dog’s heart contains two chambers: the atrium and the ventricle. When either of these chambers stop pumping blood correctly, the blood and fluid begins building up around the heart leading to canine congestive heart failure.
Two main causes of canine congestive heart failure:
- Dilated Cardiomyopathy
- Degenerative valvular disease
With degenerative valvular disease one of the valves that prevents blood from back-flowing into the other chamber of the heart begins to fail. If blood escapes one chamber while the heart is pumping, it causes an imbalance in pressure. This form of heart failure is more common in small breeds like Yorkshire Terriers.
When the cause of the congestive heart failure is related to dilated cardiomyopathy, either the left or right ventricle chamber starts growing. As one chamber is larger, the blood doesn’t move around effectively. Larger dogs, such as Great Dane, are most susceptible.
First stage of canine congestive heart failure
Generally, there is little you’ll notice during the first stage. The heart rate increases and the body adjusts to the changing blood flow by contracting the blood vessels. This triggers a bodily response to retain more sodium and water within the body. These three actions, when combined, trigger a higher blood pressure.
Some pets are diagnosed with a heart murmur years before developing congestive heart failure. If your vet hears a murmur, be aware that it may progress to congestive heart failure when your canine becomes elderly.
Signs you may see include an intolerance for exercise, coughing or wheezing when extremely active or overly excited and restlessness before going to sleep.
Advancing congestive heart failure in dogs
As the congestive heart failure progresses, symptoms become a little more obvious. Coughing and wheezing following activity occur, as well as weight loss and lack of appetite. In some dogs, abdominal swelling becomes apparent.
As pressure builds on the lungs, fluid begins developing. Pulmonary edema is a risk. If your dog begins coughing up red or pinkish foam, contact your veterinarian immediately.
Late stage canine congestive heart failure
In the latter stages of congestive heart failure, the dog becomes lethargic. He’ll breathe heavily when resting, refuse most activity and lay around all day. During activity, it isn’t uncommon for the dog to collapse or faint. The dog’s gums and tongue often turn a bluish-gray color during this fainting spell because the extremities are not getting enough blood.
What to Expect from Treatments
Dogs with congestive heart failure will be on medications to regulate the heart rhythm and to tighten blood vessels so that fluids cannot leak into the chest cavity. Low-sodium diets and diuretics are used to regulate the amount of fluid in the body. Light exercise is often advised. By Dr Ruan Du Toit Bester
Hope this info helps
Till next week
Dr Ruan Bester
Ask the Vet: Royal Veterinary Centre
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