Panting more. Getting tired on walks. Not wanting to go up or down the stairs. It’s normal for dogs to slow down as they age, but sometimes it’s more than getting older. The early signs of heart disease can be subtle, but it’s important to recognize them. Early diagnosis and treatment of some heart diseases can slow down or prevent congestive heart failure in dogs.
What causes congestive heart failure in dogs?
Heart disease, which can develop into heart failure, is commonly seen in older dogs. According to veterinary cardiologist Dr. Bonnie Lefbom, Dipl. ACVIM, incidence of heart disease varies from between 15% to 30% of older, small dogs and 5% to 15% of giant breed dogs.
Congestive heart failure, which can occur as heart disease progresses, is less common thanks to the veterinary treatments available today, but some dogs with heart disease will go on to develop heart failure. Dr. Lefbom says small breed dogs with a long-standing heart murmur are the most common patients with CHF. Large and giant breed dogs more commonly develop a weakened heart muscle.
One of the most common causes of heart failure in dogs is chronic degenerative valve disease (CVD). “Just like in older people, the heart valves can start to break down and leak, causing backflow in the heart and a heart murmur,” says Dr. Lefbom, who practices at the Regional Veterinary Referral Center in Springfield, Virginia. “Over time, with continued backflow through the valves, the heart enlarges. When the heart gets too big, fluid backs up in the lungs.”
Some breeds at higher risk for developing CVD include:
- Cocker Spaniels
- Cavalier King Charles Spaniels
- Miniature Poodles
- Miniature Schnauzers
- small Terrier breeds
Another common cause of heart failure in dogs is heart muscle disease, which is called cardiomyopathy. With this disease, the valves are OK, but the muscle of the heart thins out, which means it can no longer pump blood the way it needs to. The pump failure causes fluid to build up in the lungs or the belly, Dr. Lefbom says.
Some dog breeds are more prone to developing cardiomyopathy, including:
- Cocker Spaniels
- Doberman Pinschers
- Great Danes.
Diet and congestive heart failure (CHF) in dogs
In recent years, veterinarians have seen an uptick of canine dilated cardiomyopathy, especially in dog breeds not previously identified as being at higher risk for this disease.
“The majority of those dogs were eating new or unusual diets,” Dr. Lefbom says. “Initially, it seemed the diet problem was from foods that were grain-free. Now it appears that dog foods high in legumes (peas, lentils and chickpeas) may be causing this problem. Research is still underway to find the exact cause.”
Stages of congestive heart failure in dogs
Heart failure occurs in stages. According to Dr. Lefbom, early heart failure is very responsive to treatment and dogs start feeling better quickly once they receive care. A dog in the middle stages of heart failure is harder to treat and requires more medication. The late stages of heart failure are the most severe, requiring multiple medications given many times throughout the day. In the late stages, the dog’s quality of life worsens. At this point, pet owners might face the difficult decision to consider humane euthanasia.
Signs of congestive heart failure in dogs
The signs of early congestive heart failure in dogs might not be noticeable at first, especially to the untrained eye. It could be as small as the dog not wanting to go for walks anymore or not go up and down the stairs as frequently. As heart disease progresses, you might notice light coughing, especially in the morning, or see that your dog is breathing faster, even when resting.
Reluctance to move around could also be signs of aging or arthritis. Even little changes in your dog’s behavior or activity are worth checking out with a visit to the veterinarian.
“In the middle stages of heart failure, the dog may start having trouble breathing during exercise or may not be sleeping through the night without coughing,” Dr. Lefbom says. ”The more severe stage of heart failure requires emergency care for a pet that is truly struggling to breathe.”
If you know your dog has heart disease, ask your veterinarian which worsening signs you need to look out for and bring to their attention.
How is congestive heart failure in dogs diagnosed?
Your veterinarian can listen for a heart murmur to diagnose heart disease. Heart murmurs are graded from 1 to 6, with 1 being the least severe and 6 being the most severe.
If your vet is concerned your dog might have congestive heart failure, she will suggest taking X-rays of the dog’s heart and lungs to look for heart enlargement and fluid in or around the lungs.
Although your primary care veterinarian can treat your dog for congestive heart failure, she might refer you to a veterinary cardiologist for further treatment. Board-certified cardiologists are heart specialists who only treat pets with cardiac issues, so they are experts at diagnosing, treating and managing CHF. A cardiologist works together with your regular vet to implement a treatment and monitoring plan for your dog.
What treatments are available for congestive heart failure
Although congestive heart failure in dogs cannot be cured, it can be managed with medications. The goal is improving the dog’s quality of life and extending longevity.
“Veterinarians and veterinary cardiologists treat heart failure using many of the same medicines used for people with CHF,” Dr. Lefbom says. “A common example is the drug called Lasix, or furosemide, to help clear fluid from the lungs.”
With proper treatment, most dogs with CHF can live relatively normal lives. Your veterinarian might recommend some lifestyle changes, for instance, decreasing intense activities like ball chasing. Dogs with CHF generally self-limit, seeming to know how much activity is OK and when it’s time to back off. However, Dr. Lefbom says the most important thing is to keep the dog doing at least some of what they love.
How long can a dog live with congestive heart failure?
On average, dogs diagnosed in the early stages of congestive heart failure and treated appropriately can live comfortably for about one to two years.
A study conducted in 2015 showed that dogs with congestive heart failure live 75% longer when treated by a veterinary cardiologist who works closely with your primary care vet.
Is it best to avoid grain-free diets for dogs with heart disease?
Though no definitive conclusions have been made, veterinary researchers, nutritionists and the FDA continue to investigate the cause of diet-induced heart muscle disease (dilated cardiomyopathy). This leaves many pet owners wondering if they should avoid feeding grain-free diets, especially for dogs with heart disease or at risk for heart disease.
“Feeding a grain-free diet may have less to do with the problem, and the bigger concern seems to be dog foods with high levels of peas, lentils and chickpeas (legumes),” Dr. Lefbom says. “With so many diets on the market, there is no easy answer to what to feed each individual dog.”
Your best bet is to talk to your veterinarian about the best food to feed your dog, and what types of formulations or ingredients to avoid.