What Is Congestive Heart Failure?
Congestive heart failure occurs when heart disease progresses to the point where the heart can’t pump blood effectively enough anymore. As a result, fluid builds up in the lungs and other parts of the body (this is called congestion).
In some dogs, heart disease will gradually get worse over time, to the point where heart failure eventually develops. Treating some dogs before heart failure develops will help them stay symptom-free for longer, enabling them to enjoy life to the fullest. Early diagnosis of heart disease and regular, proactive monitoring are therefore the keys to the best long-term outcomes.
In this article we’ll explore the causes of heart failure, the signs to look for, and how you can take proactive steps to keep your dog happy for as long as possible.
Heart disease is common, affecting around 1 out of every 10 dogs seen in veterinary clinics.1,2 There are several different types of heart disease that can cause heart failure, but 9 out of 10 dogs with heart disease have 1 of just 2 diseases.3
The 2 most common causes of heart failure in dogs are:
- • Heart valve disease
- • Dilated cardiomyopathy
Heart Valve Disease
Heart valve disease is by far the most common cause of heart failure in dogs. Around 75% of all heart disease in dogs seen in practice is mitral valve disease (MVD).2,4,5 The mitral valve normally seals to stop blood flowing backward when the heart pumps. In mitral valve disease the valve slowly becomes misshapen over time, eventually becoming leaky. When the heart pumps, this leaky valve allows some blood to flow backward, so the heart has to work harder to be as effective.
Heart Valve Disease Facts
- Causes 75% of heart disease in dogs seen in practice
- Affects middle-aged and older, small and medium breed dogs
- Causes a leaky heart valve
- First sign is a heart murmur
Myxomatous Mitral Valve Disease (MMVD)
MMVD is most common in small and medium breed dogs, especially as they get older. The first sign tends to be a heart murmur, normally picked up by a veterinarian at a routine health check.
Dog Breed Predisposed to MMVD
Dilated Cardiomyopathy (DCM)
DCM in dogs causes the heart muscle to become weak and flabby, so it can’t contract and pump blood efficiently. Dilated cardiomyopathy is most common in large and giant breed dogs. Unlike heart valve disease, the signs of dilated cardiomyopathy can occur suddenly, so regular heart health checks are important to pick it up early.
Dilated Cardiomyopathy Facts
- The second most common heart disease in dogs
- Affects large and giant breed dogs
- Causes the heart muscle to become weak
- Signs can appear suddenly
Dog Breed Predisposed to DCM
Signs of Heart Failure
In the early stages of heart failure, you may not notice any signs, but as it progresses, they will become more obvious.
The most common signs of heart failure in dogs are:
- Coughing
- Difficulty breathing
- Rapid breathing
- Difficulty exercising
- Weakness or lethargy (tiredness)
- Fainting episodes or collapse
- Gray or blue gums
- Swollen belly
Sometimes these signs are subtle and can be mistaken for a dog that is just getting older and “slowing down.” If you notice any of these signs, it is best to get your dog checked by a veterinarian to make sure.
Testing
If your veterinarian suspects heart failure, they’ll recommend some tests to confirm their diagnosis and identify which heart disease is causing the problem.
These tests could include:
- Blood and urine tests
- Chest X-rays to see the heart size and shape, blood vessels, and lungs
- Ultrasound to look at the inside of the heart and how well it’s working
- An electrocardiogram (ECG)
Sometimes your veterinarian will recommend a referral to a veterinary cardiologist.
These tests aren’t just used to diagnose heart failure; they also provide useful information to stage heart disease before heart failure develops. This helps veterinarians decide when they should start treatment.
Many dogs with heart disease will benefit from receiving treatment before they develop heart failure.
Treatments
Although heart failure can’t be reversed, it can be slowed with medicines, and the symptoms of heart failure can be managed to help dogs feel better. There are 2 aims of treating a dog with heart failure:
1. Remove Excess Fluid From the Body
This is done with diuretics, such as furosemide or torsemide. Diuretics make dogs urinate more than usual, so make sure your pup has plenty of potty breaks.
2. Help the Heart Function the Best It Can
The most common medicines used for this are inodilator, angiotensin-converting enzyme (ACE inhibitors), and spironolactone. Most dogs with heart failure may be on 3-4 different medicines to keep them feeling well.
Prevention and Early Intervention
Some breeds are more at risk of heart disease than others, but there are steps that you can take to help keep your dog’s heart healthy:
- Keep your pet at a healthy weight
- Feed a balanced, nutritious diet
- Give your dog frequent cardiac exercise
- Visit your veterinarian regularly
- Give regular parasite preventives
- Look after your dog’s teeth (there’s a link between dental disease and cardiac disease)
Key Takeaways
Early diagnosis and management are crucial for managing heart failure and, sometimes, also delaying it.
Treatment will involve lifelong medications, but affected dogs can have a good quality of life.
Regular visits to your veterinarian are essential to diagnose heart disease early and to keep your dog happy and healthy for as long as possible.
