Just as with humans, our pets can be prone to heart conditions, especially as they get older. While dogs and cats do not commonly get heart attacks like humans, they are commonly prone to another group of heart conditions known as congestive heart disease.
What is congestive heart disease?
Congestive heart disease is characterised by inefficient and sluggish blood flow in the body due to abnormalities in the heart.
In order to understand why pets develop congestive heart disease, it is important that we familiarise ourselves with the structures within the heart. The heart is made up of left and right sides. Each of these sides is divided further into upper and lower chambers, which are separated by one way flaps/valves that ensure that blood flows smoothly in one direction through the heart and blood vessels.
Common causes of congestive heart disease include:
- Thickening of heart valves due to bacterial infection (commonly from bacteria spread from bad teeth) or wear and tear of valves with age,
- Defects in heart valves or holes between the heart chamber walls from birth, and
- Abnormal changes in the heart muscle wall with age.
The traffic jam
The above-mentioned defects in the heart lead to an increase in blood pressure in the blood vessels as blood flows in a turbulent two directional manner rather than the normal one way smooth flow. When the congestion and blood pressure is too great, fluid in the blood vessels have nowhere to go, so it starts to leak out into various organs such as the lungs, chest cavity or belly cavity. Think of it as cars stuck in a traffic jam trying to detour out of the congested road. The inefficient flow of blood around the body also means less oxygen is carried to various organs. When these signs develop, congestive heart disease progresses to congestive heart failure.
What will I notice if my pet develops congestive heart disease?
Pets affected with early stages of congestive heart disease commonly show no signs of illness. However, a physical examination by your veterinarian may pick up a heart murmur. This is commonly the first and only sign of congestive heart disease.
Are some breeds more prone than others?
Congestive heart disease can affect any pet, but some breeds of dogs and cats are more prone than others.
Cavelier King Charles Spaniels have a particularly high genetic predisposition to heart disease secondary to degenerative heart valves. Other commonly affected breeds include Shih Tzus, Lhasa Apsos, Miniature and Toy Poodles, Dachshunds, Cocker Spaniels, Miniature Schnauzers and other terrier breeds.
Some large breed dogs are prone to reduced ability of the heart muscle wall to contract (dilated cardiomyopathy, or DCM), including Dobermann Pinschers, Newfoundlands and Boxers.
Cats are generally prone to abnormal thickening of the heart muscle walls (hypertrophic cardiomyopathy, or HCM). Both purebreds such as Persians, oriental breeds and American Shorthairs, and domestic short hair cats can be affected. Cats that are not receiving a complete and balanced diet can also suffer from DCM related to taurine deficiency.
How do I know how severe my pet’s heart condition is?
Once your veterinarian diagnoses your pet with a heart murmur, these diagnostics test may be recommended:
- Chest x-rays: To assess the size of the heart, blood vessels of the lungs and clarity of the lungs,
- Heart ultrasound (echocardiography): Allows for a more thorough assessment of the various chambers, valves, muscle walls and contractility of the heart ,
- Electrocardiogram (ECG): To diagnose an abnormal heart rhythm (arrythmia).
- These diagnostic tests will allow your veterinarian to better understand the cause and severity of the heart condition so that an appropriate management plan can be developed.
How can I help my pet?
Treatment for congestive heart disease/failure is aimed at relieving the consequences of the structural heart defect and improving heart function. Treatment options include:
- Medications: When a pet is experiencing heart failure, medications to decrease blood pressure, dilate blood vessels and improve heart muscle function are usually prescribed by your veterinarian. Before your pet is at the stage of heart failure, there is no evidence that starting these medications early will help delay the onset of heart failure.
- Diet: A low sodium diet can help prevent excessive blood pressure, helping to ease the effects of congestive heart failure. Prescription diets made specifically for dogs with heart disease are typically low in sodium and may also contain supplements to enhance heart function.
- Supplements: Co-enzyme Q10, L-carnitine, omega-3 oils and Hawthorn are some supplements that can assist in optimising heart function. These supplements may be beneficial even before heart failure sets in.
Is prevention better than cure?
While it is difficult to prevent the common causes of heart failure such as degenerative valve disease, some causes such as bacterial infection of heart valves secondary to dental disease can easily be prevented by regular brushing of your pet’s teeth coupled with professional veterinary dental scaling to ensure that your pet’s pearly whites do not become a home for nasty bacteria that travel in the bloodstream to other organs such as the heart.
It is also essential that your pet receives regular check ups at least once a year, as a heart murmur is most commonly the only early sign of a heart issue. If a heart murmur or arrythmia is detected, it is important to discuss the need for further diagnostic investigation and management of the heart disease with your veterinarian.
If you pet is already on medication for heart failure, it most likely needs it for life. Ensure that you always have sufficient amount of medications available, and arrange for timely rechecks as recommended by your veterinarian as the dose or types of medications needed may change with time.
Every life is dependent on a well functioning heart, and your pet depends on you to ensure that it’s heart stays in good shape. I have too often seen senior dogs or cats that had not seen a veterinarian for years coming to the clinic with severe breathing distress due to undiagnosed heart failure that had been brewing over the years. It is heartbreaking that some of these pets would have survived if they were brought in to the veterinarian earlier. Get your pet’s heart and general health checked today if it has been more than a year since that last vet visit!
The Top 5 Signs of Congestive Heart Failure
- Breathing difficulties
- pale/blue gums
- decreased energy levels
- loss of appetite
Left untreated, these signs can rapidly lead to sudden death. It is essential that you recognise that these signs may mean that your pet is in an emergency situation and needs immediate veterinary attention.