Skip to main content

How long can an old dog live with a heart murmur?

Does your old dog have a heart murmur? This guide will help you and your pet

A man hugs a golden retriever, facing away from the camera
Eric Ward / Unsplash

Learning that your senior dog has a heart condition can feel devastating. It forces you to contemplate the idea that your best friend won’t be around forever. But while the diagnosis of a heart murmur can be scary, there is no reason to jump to the worst-case scenario. Murmurs range in severity; while some are serious, others are less so. Before you start frantically Googling “old dog heart murmur life expectancy,” keep reading to learn more about the different types of heart murmurs, the prognosis, and how you can help your pup live a long and content life.

Man in a plaid shirt hugging his dog
Roman_studio / Shutterstock

What is a heart murmur?

Like us, dogs’ hearts pump blood throughout their bodies, creating a steady beat that can be heard through a stethoscope. If there is a disturbance in the blood flow, it makes a noise distinct from a regular heartbeat called a murmur. There are a few different ways vets classify heart murmurs: type, grade, and configuration.

The type is based on when in the beating cycle the murmur takes place. The three types of murmur are systolic, diastolic, and continuous; knowing the type of murmur can help the vet determine its cause. The grade of the murmur lets the veterinarian know how loud it is. Murmurs are graded on a scale of one to six, with one being barely detectable with a stethoscope and six being the most severe and loudest. The doctor will also be able to uncover the heart murmur’s configuration. This classification describes the way murmurs sound and separates them into four categories: plateau, crescendo-decrescendo, decrescendo, and machinery. Your vet can explain which of these categories your dog’s murmur fits into so you can learn more about their condition.

A cavalier king charles spaniel lies on the floor and looks up with big sad eyes
PicsbyFran / Pixabay

How serious is a heart murmur in older dogs?

In general, murmurs can be difficult to predict because there are so many varieties and degrees of severity. As such, life expectancies differ based on a few factors, including the type of murmur and even the breed of dog. Some pups can have murmurs for years without ever developing heart disease. Others, though, may progress to congestive heart failure rapidly. Certain breeds are more likely to develop heart disease. These breeds include Chihuahuas, Boxers, Dobermans, and Cavalier King Charles spaniels. But even with congestive heart failure, pups can survive for years with medication and attentive care.

While they may sound scary, heart murmurs are not always dangerous. If your senior pup has a low-grade murmur and no accompanying symptoms, there is little cause to worry. Your vet will likely recommend monitoring your dog’s condition to make sure it doesn’t decline. Remember that heart murmurs typically occur in older dogs because of an underlying health condition. Many of these causes are treatable and may even resolve on their own. However, the outlook may be more guarded in more severe cases, especially with older dogs. Your veterinarian is the best person to talk to about your dog’s prognosis.

Vet listens to a dog's heart and lungs
Sergey Mikheev / Shutterstock

Monitoring and treatment can help your dog’s health outlook

Early diagnosis and treatment are vital to giving your pup the best chances of survival. It’s crucial to know that vets don’t treat the heart murmur itself; they focus on the symptoms and underlying issues associated with the murmur. The treatment plan and prognosis both depend on the cause of the murmur. Follow the vet’s recommendations and closely monitor your pet’s health to assess whether the murmur indicates a more serious heart condition. You should also research the symptoms of heart disease in dogs so you know more about what to watch for.

The vet may recommend that you monitor your pup’s breathing rate when he’s resting or sleeping, as well as his diet and activity levels. They can also advise you on which type of dog food is best for your dog’s condition. General guidelines are that dogs with heart disease must be on a low-sodium diet. You’ll also need to keep an eye on your pet’s potassium and phosphorus levels.

The veterinarian can also tell you how much exercise your dog should be getting. Too much strenuous activity can be hazardous for a pup with heart disease.

In addition to extending their life, one of the main goals of heart disease treatment is ensuring the dog retains a high quality of life post-diagnosis. By working with your dog’s vet, monitoring the dog’s condition, and managing their health properly, you can help ensure that they continue to live a happy life for as long as possible.

A man dressed in a Jacket holds his black and brown dog in his arms and kisses the dog
Chewy / Unsplash

What are the grades of heart murmurs in dogs?

Heart murmurs are graded on a scale of one to six based on severity. Veterinarians use these grades to inform the next steps, if any, such as treatment. The six grades are:

  • Grade 1. These heart murmurs in dogs are soft — the vet could barely hear the issue. Grade 1 heart murmurs are considered the least serious of the six.
  • Grade 2. A vet can hear the murmur’s soft sound when using a stethoscope.
  • Grade 3. These heart murmurs in dogs are more serious. The doctor will classify a Grade 3 heart murmur as “intermediate loudness.” The murmur radiates in multiple spots.
  • Grade 4. These heart murmurs range from moderate to intense. The vet can hear the murmur on both sides of your pet’s chest.
  • Grade 5. These murmurs are some of the most serious. They’re loud, and the vet doesn’t need to put much effort or pressure on the chest with a stethoscope to know that the dog has a murmur. In fact, the vet can feel the murmur by placing their hand on the pup’s chest.
  • Grade 6. These are the most serious heart murmurs. Grade 6 heart murmurs are loud and detectable by touching the chest with a hand.
a tri-color dog sitting on sidewalk
Alexander Dummer / Pexels

Don’t give up hope

When anyone brings up a heart murmur, you likely assume the worst. But the causes of murmurs in canines are so widespread, and the severity depends on so many factors that it’s challenging to know what to expect just from those two little words. There is still hope for your dog; many pups, even older ones, can live long, happy lives after their diagnosis. Your veterinarian can clarify your dog’s condition and what to expect in the coming months and years. With an early diagnosis, expert treatment, and regular monitoring, you can provide your dog with the best life possible, even with a heart murmur.

Editors' Recommendations

Shannon Cooper
Former Digital Trends Contributor
Shannon Cooper has written about everything from pet care and travel to finance and plumbing in her seven years as a writer…
What to do if your dog keeps throwing up with no sign of stopping
Here's what to try first and when to call the vet
A dog sleeping in a bed with a water bottle on his head and a thermometer in his mouth.

If you're like most pet parents, the sight of your beloved dog throwing up sends shivers of fear down your spine. Just like us, dogs occasionally eat something that disagrees with them and causes them to vomit. In most cases, your dog's vomiting will resolve on its own, but if your pup keeps throwing up, it could be cause for concern.

We'll give you the rundown on everything you need to know about why your dog keeps throwing up, from potential reasons why your pet might be vomiting to when you should take your pooch to the vet. 

Read more
Can dogs eat celery? The do’s and don’ts you should know
Your pup will probably love a veggie snack now and then
Woman chops up veggies including celery for her dog

Your dog's favorite snacks might include dog biscuits, fancy chews, or even that bacon you dropped on the floor one time, but can dogs eat celery? The truth is lots of dogs like veggies, even bland ones such as celery. While you wouldn't want this green and healthy nibble to become a staple in their diet, you can absolutely give your pup a celery snack now and then — and they might grow to love it.

Can dogs have raw celery?
As omnivores, our pet dogs need a balanced diet of both meat and plants. That's likely because their domestic history made them into scavengers thousands of years ago when our ancestors were still in the hunter-gatherer phase. In modern times, this diet preference has huge benefits because you can throw in some healthful treats that will give your pup a nutrition boost and keep them full.

Read more
Why do dogs hate cats? The truth behind this age-old grudge
Find out what's behind the dog and cat rivalry that's been around forever
A black pug and a tabby cat sit on a table

Even if you've never been around dogs or cats, you've probably heard about their rough relationship. Cats and dogs are rivals at best and enemies at worst -- right? It sure seems that way when there are thousands of stories and even videos of dogs and cats not getting along. Whether you've witnessed a dog-cat chase with your own eyes or have heard your pup barking at the neighbor's cat at all times of the day, it's only natural to wonder, "Why do dogs hate cats?"
Some dogs couldn't care less if a feline friend stopped by for a visit -- that's true -- but plenty of other pups would go positively bananas. So what's the difference?

Why do dogs hate cats?
While it's easy to assume that dogs and cats "hate" one another because of their vast differences, it's a bit more complicated than that. Even dogs that regularly chase cats don't do so out of malice or hate. It's an instinctual thing!

Read more