Dog Heart Murmur -What Does It Mean? Is it Serious? │ Twin Trees Vet Talk (FREE VET ADVICE PODCAST)

My vet said my dog has a heart murmur- What does it mean? Do I need to do anything? Should I be concerned?

On today's episode of Twin Trees Vet Talk, we welcome our very special guest, Dr. Mark Harmon. Dr. Harmon is a Veterinary Cardiology Specialist at Boundary Bay Veterinary Specialty Hospital in Vancouver, BC (Canada).

We discuss the causes of heart murmurs and the steps a pet owner should take to find out the significance of the heart murmur and whether indicative of a serious heart problem. If your vet detects a heart murmur in your pet, a referral to a cardiologist can provide you with important information about what is causing the murmur and if any intervention is needed. The cardiologist will perform an electrocardiogram (EKG or ECG) to assess the heart rhythm, and an echocardiogram (ultrasound of the heart) to assess size, shape, and function of the heart, and to detect any structural or functional abnormalities. Sometimes additional tests may be needed.

If your pet has any indication of heart disease (even a very soft murmur, exercise intolerance, shortness of breath, cardiac arrhythmia, etc.) it very is important to have the heart evaluated, and to see a cardiologist whenever possible. If heart disease goes undiagnosed, it can continue to get worse under the surface and eventually culminate in a big emergency like congestive heart failure (CHF). We hope you enjoy this episode! Please leave your questions and comments below!

-Signs Of Heart Disease In Dogs And Cats │ Twin Trees Vet Talk (FREE VET ADVICE PODCAST)
-The Amazing World Of Veterinary Cardiology: 
-IT'S NOT OVER! Grain Free Dog Food & Heart Disease│Twin Trees Vet Talk (FREE VET ADVICE PODCAST)
-Congestive Heart Failure in a Dog / CHF | Cute Patients 
- 3 Tips from the Emergency Vet │ Twin Trees Vet Talk (FREE VET ADVICE PODCAST)   
-1.7 Preventative & Wellness Care for Pets (Dangers to Avoid #7 of 7) 
-Genetic Heart Disease | Pet Parenting 101 

-Diet-associated DCM update from Lisa Freeman (Board-Certified Veterinary Nutritionist at Tufts University): 
-Orthopaedic Foundation for Animals:
-AKC Guide to Responsible Pet Breeding:


-Until you know exactly what you're dealing with, you don't really know the consequence of the heart disease. And that's where cardiologists can be so helpful, is getting an accurate diagnosis.
-Just the murmur itself- that's just a noise, like when your car makes a noise.
- We just don't know until you look, and sometimes we look and we're like- there's something serious here, we need to be proactive about it. Cats are very different with their heart disease. Sometimes they sound totally normal and when you look under the surface they can have very very serious things [Music]

[Dr. Lopez]: We have a very special guest, Dr Mark Harmon. He is a board certified veterinary cardiologist at Boundary Bay Veterinary Specialty Hospital. Let's do this one: My dog has a heart murmur but she seems fine. What does it mean?

[Dr. Harmon]: Yeah I think this is a great question. So a heart murmur is generally just due to something like a leaky valve or maybe a hole in the heart, like a congenital thing that they're born with that shouldn't be there, or a vessel that stays open. But really the consequence of a heart murmur you cannot say until you know what you're dealing with. So the murmur intensity or how loud it is...some people will assume that, well if it's a soft murmur then that's probably okay, and if it's a loud murmur that's bad. But that's completely dependent on the disease that you're dealing with. So dogs that have dilated cardiomyopathy- those dogs often have very soft murmurs to potentially no murmur present and they can have very serious heart disease. Whereas dogs with chronic age-related sort of changes to their valves in their heart may have murmurs for years and years and years and may never develop problems from it. Certain things, with congenital heart disease, loud murmurs are actually better than soft heart murmurs. So until you know exactly what you're dealing with, you don't really know the consequence of the heart disease, and that's where cardiologists can be so helpful is getting an accurate diagnosis as to what you're dealing with, and saying well this is something we do need to worry about or saying you know we're lucky this very loud murmur is actually something that we are happy that it's a loud murmur this situation because it's actually a very minor defect. So you really need more information to be able to make those best decisions for your pets as far as: is this something we need to worry about or not.

[Dr. Lopez]: yeah just the murmur itself that's just a noise like when your car makes a noise.

[Dr. Harmon]: Exactly.

[Dr. Lopez]: You know you need to find out what's causing the noise, get the diagnostics done, see a cardiologist, because then they can tell you what's causing that noise, how serious it is.

[Dr. Harmon]: Yeah exactly, exactly. And not all noises that we hear when we listen to these animals are going to be significant. We love to give that news, that thankfully it's something that's benign or that's not going to be a problem and that they can kind of go on with their day-to-day life. But at the same time, we just don't know until you look and sometimes we look and we're like there's something serious here and we need to try to get on this and be proactive about it.

[Dr. Lopez]: Yeah. So when the cardiologist is assessing it to try to see what's causing it, usually you're going to want to run special tests just like a mechanic would do, looking under the hood, to see what what's making that noise.

[Dr. Harmon]: Exactly. We do ECGs because anytime you have any concerns about heart disease, arrhythmias or abnormal heart rhythms can be a problem, or conduction problems within the heart. So it looks at the electrical side of things. Whereas the echocardiogram looks into the heart and you can actually see: how well is the heart pumping? how big are these heart chambers? how well are these valves working? are there any holes that shouldn't be there? And so you can put that information together, and say, well these are the things that we have going on, and determine its real significance.

[Dr. Lopez]: So an echocardiogram, which is an ultrasound of the heart and an EKG or electrocardiogram to look at the rhythm.

[Dr. Harmon]: Really, those get us the vast majority of the way there for most cases.

[Dr. Lopez]: That's very helpful. Yeah a lot of times it just comes as such a shock when dogs come in in heart failure. And they're like, "But he was fine, he's the fastest runner! Oh, but he's had that heart murmur..."

[Dr. Harmon]: We see this all the time too on our side of things.

[Dr. Lopez]: Just like if you have a noise coming from your engine, if you keep driving around like that, maybe your car will still run fine ...until one day. That's what happens when bad hearts decompensate. Over time, if you do have a problem, it just gets worse and worse, and then eventually it turns into an emergency.

[Dr. Harmon]: Yeah exactly. And I would say like the addition part to that, because you know we're talking primarily about dogs in that situation, is cats are very different with their heart disease. They can have heart murmurs sometimes, they can have other heart sounds that we can pick up on such as gallops that we can hear ,sometimes they sound totally normal though. So if pet owners look at their animals and they do feel like something's off with how they're breathing or anything like that, they should definitely start by seeing their vet and potentially getting chest x-rays, because cats can actually sound quite normal on the surface and then when you look under the surface they can have very very serious things going on. So they're very good at hiding things from us.

[Dr. Lopez]: That's really good to know.


00:00 Teaser
0:39 Intro, heart murmur- what does it mean?
1:12 loud vs soft murmur
1:49 why to see a cardiologist
2:55 ECG and echocardiogram
3:50 heart failure
4:18 cats are different


WELCOME TO TWIN TREES VET TALK! An informal chat with Dr. Lopez (Emergency Veterinarian) and friends to share our perspective on pet predicaments, being a veterinarian, our shared love for animals and more! Have a quick question? Want to run something by us? Or just need our two cents? This is your chance! Each week we select a handful of questions to answer.




1) DON'T WAIT TOO LONG TO GET HELP! If you wait too long, it could be too late. This is especially true for concerns such as laboured breathing, pale gums and weakness. You know your pet best, so if you are worried or concerned, "when in doubt, check it out!"

2) PREVENT THE PREVENTABLE. Learn as much as possible about dangers that face your pet, such as household poisons, seemingly harmless objects (like toys, clothing, garbage and rocks), other animals, and vehicles. Pets are like toddlers and they need a responsible adult/babysitter to protect them from danger. Puppies and kittens need to start their vaccines at ~8 WEEKS (and they need boosters too!) to protect them from deadly diseases.

3) BE PREPARED FOR THE WORST CASE SCENARIO. Have a plan in place, know your nearest emergency clinic, have the ASPCA phone number on speed dial. Know basic first aid training and CPR. But MOST IMPORTANTLY, BE FINANCIALLY PREPARED. The cost of medical treatment in an emergency, and the owners' ability to pay for it, is probably the most important factor that determines whether a pet will receive the medical care it needs. The best way to protect yourself is to have good medical insurance for your pet. Do your research.

**REMEMBER**: WE ARE ALL ON THE SAME TEAM, with the best interest of the patient as everyone's first priority. Let your vet do what he/she does best, and don't try to grab the steering wheel and obstruct your vet from doing his/her job. We are all in the same car, we are all headed to the same place, but only one of us has the driver's license (meaning, only the vet has the medical training and background to "drive the car"). 


The medical information on this site is provided as an educational resource only, and is not to be used or relied on for any diagnostic or treatment purposes. This information does not create any veterinarian-client-patient relationship, and should not be used as a substitute for professional diagnosis and treatment.

Please consult your pet's health care provider before making any health care decisions or for guidance about a specific medical condition. Twin Trees Vet expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site.

#doghealth #heartdisease #cardiology #veterinarysurgeon #veterinarian #pethealth #pets #veterinaria #heartsounds