What to Expect at Your Dog's Vet Visit for a Heart Murmur

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-14

Key Takeaways

• A heart murmur is an abnormal sound detected via auscultation, indicating turbulent blood flow through the heart, not a disease itself; its significance is determined by diagnostic workup, not solely its grade.
• Emergency signs requiring immediate veterinary attention include collapse, pale/blue gums, severe respiratory distress, or inability to stand, indicating potential life-threatening cardiac compromise.
• Diagnostic evaluation typically involves a physical exam, auscultation, pulse palpation, and may include echocardiography (ultrasound of the heart), chest X-rays, blood pressure measurement, and blood tests like NT-proBNP to assess cardiac function and structural integrity.
• Echocardiography is the definitive diagnostic tool, visualizing cardiac chambers, valves, and contractility to identify the cause of the murmur, such as valvular insufficiency or congenital defects.
• Management strategies range from routine monitoring for benign murmurs to pharmacotherapy (e.g., diuretics, ACE inhibitors, positive inotropes) for dogs with diagnosed heart disease, aiming to slow progression and maintain quality of life.
• Regular follow-up examinations and home monitoring of resting respiratory rate are critical for early detection of disease progression or medication side effects, allowing for timely therapeutic adjustments.

If your veterinarian just told you that your dog has a heart murmur, you are probably worried. Here is the short version: a heart murmur is an abnormal sound in the heartbeat, and it is common in dogs. It does not automatically mean your dog is dying, but it does mean your dog needs a careful workup to find the cause. That workup usually happens over one or two visits, and it is mostly painless and low-stress for your dog.

The first thing to know is that most heart murmur evaluations are routine, not emergencies. You have time to breathe, ask questions, and book a proper appointment. However, a few signs mean you should stop reading and go to an emergency vet right now. If your dog is collapsing, struggling to breathe, has pale or blue gums, or cannot stand, do not wait for a scheduled visit. Those signs can indicate a life-threatening heart problem, and your dog needs in-person emergency care immediately.

At a routine visit, your vet will listen to the murmur, grade its loudness, and likely recommend tests to see how well the heart is pumping and whether the murmur is causing damage. This article walks you through exactly what happens, what the tests cost in general terms, and what the results mean for your dog's daily life.

Is This an Emergency?

Use this table to decide how quickly to act. If you are ever unsure, call your vet's office. They can tell you whether to come in now or book an appointment.

{
 "type": "triage",
 "title": "Urgency triage by severity of signs",
 "tiers": [
  {
   "tier": "danger",
   "label": "Go to an emergency vet now",
   "signs": [
    "Collapse or fainting, gums that are pale, white, blue, or gray, open-mouth breathing that does not stop, a resting breathing rate over 30 breaths per minute, inability to stand or walk, coughing up frothy pink fluid"
   ],
   "action": [
    "Do not wait",
    "Drive to the nearest open emergency clinic",
    "Call ahead if you can"
   ]
  },
  {
   "tier": "warn",
   "label": "Book a same-day appointment",
   "signs": [
    "New or sudden coughing, especially at night, a resting breathing rate that climbs from normal to over 30 breaths per minute over a day or two, reduced appetite, lethargy that is clearly worse than usual, a swollen belly that feels tight"
   ],
   "action": [
    "Call your regular vet first thing in the morning",
    "Describe the signs",
    "They will fit you in today"
   ]
  },
  {
   "tier": "safe",
   "label": "Watch at home for 24 to 48 hours",
   "signs": [
    "A murmur found during a routine exam with no other signs, normal energy, appetite, and breathing, occasional mild coughing after drinking water or pulling on the leash"
   ],
   "action": [
    "Keep a log of your dog's resting breathing rate and energy",
    "Book a regular appointment within a few days",
    "Do not exercise your dog hard in the meantime"
   ]
  }
 ]
}

What a Heart Murmur Actually Is

A heart murmur is not a disease. It is a sound. When your vet listens with a stethoscope, a normal heartbeat sounds like a steady "lub-dub." A murmur is an extra whooshing or swishing sound between those beats. It happens when blood flows through the heart in a way that is not perfectly smooth, such as through a leaky valve or a narrow opening.

Your vet will grade the murmur from 1 to 6. Grade 1 is very soft and hard to hear. Grade 6 is loud enough to feel through the chest wall. The grade tells your vet how loud the sound is, but it does not tell you how sick your dog is. A grade 3 murmur can be harmless in one dog and serious in another. That is why the murmur alone is not the diagnosis. The diagnosis comes from the tests that follow.

What Your Vet Will Do First

The first step is a full physical exam. Your vet will listen to the heart on both sides of the chest, feel the pulse in your dog's legs, and check the color of the gums. Pale gums can mean poor blood flow. Your vet will also feel your dog's belly for an enlarged liver or fluid buildup, both of which can happen when the heart is not pumping well.

Your vet will ask you questions about your dog's daily life. Be ready to describe how fast your dog breathes when resting, whether your dog coughs at night, how far your dog can walk before getting tired, and whether your dog has ever fainted. These details matter more than the murmur grade. A dog with a loud murmur but no symptoms often does better than a dog with a soft murmur who is coughing and tired.

The Tests Your Vet Will Recommend

Most dogs with a heart murmur need a few tests. These are not optional extras. They are the standard way to tell a harmless murmur from a dangerous one.

The first test is usually an echocardiogram, which is an ultrasound of the heart. It is painless and does not require sedation in most dogs. Your dog lies on a table while a technician or cardiologist moves a wand over the chest. The images show the heart's chambers, valves, and how well the heart muscle squeezes. This is the single most useful test for a murmur because it shows the actual cause.

Your vet may also recommend chest X-rays. These show whether the heart is enlarged and whether fluid is building up in the lungs. X-rays require your dog to hold still for a few seconds, and some dogs need mild sedation.

Blood tests are often part of the workup. A standard blood panel checks kidney and liver function, which matters because some heart medications affect those organs. A special test called a proBNP test measures a hormone the heart releases when it is stretched. High levels suggest the heart is working harder than it should. Your vet may also check blood pressure, since high blood pressure can strain the heart.

What the Results Mean

The results will place your dog into one of two broad groups. The first group is dogs with a murmur but a structurally normal heart. This is common in young puppies, where the murmur often disappears by adulthood, and in some older dogs with a slightly thickened valve that does not leak. These dogs usually need no treatment, just rechecks every six to twelve months.

The second group is dogs with actual heart disease, most commonly a leaky mitral valve. This is the most frequent heart condition in small breed dogs. The leak lets blood flow backward in the heart, which over time enlarges the heart and can lead to heart failure. If the tests show this, your vet will likely start medication and schedule regular rechecks. The goal is not to cure the leak, because it cannot be cured. The goal is to slow the damage and keep your dog comfortable for as long as possible.

Your vet may refer you to a veterinary cardiologist for the echocardiogram. That is normal and does not mean your dog is in crisis. Cardiologists have specialized equipment and experience, and they often work with your regular vet to manage the condition over time. The cost of a cardiology consult and ultrasound varies widely by region and clinic, so ask for an estimate before you book. Prices can range from a few hundred to over a thousand dollars, but that figure is only general context, not a quote.

The most important thing to remember is that a murmur diagnosis is a starting point, not a final verdict. Many dogs with heart murmurs live happy, active lives for years. The workup tells you what you are dealing with, and the treatment plan that follows is built around keeping your dog's quality of life high. Your vet will guide you through each step, and you can ask questions at any point. You are not alone in this, and your dog is not in immediate danger just because of the murmur itself.

What You Can Do at Home Right Now

If your dog has a heart murmur and is otherwise eating, drinking, and acting normally, you do not need to rush to an emergency clinic. You do need to gather information and book a regular appointment with your veterinarian. Plan for that visit within a few days, not months.

Start keeping a simple daily log. Write down three things: your dog's breathing rate when resting, their energy level, and any coughing. To measure resting breathing rate, wait until your dog is sound asleep. Count how many times their chest rises in one full minute. Do this at the same time each day. A normal resting rate is usually under 30 breaths per minute, but your vet will tell you what is normal for your dog. If the rate climbs steadily day after day, that is a warning sign.

Watch your dog's gum color. Lift the lip and look. Healthy gums are pink, like bubblegum. Pale, white, blue, or gray gums are an emergency. Also watch for these signs: coughing that is worse at night or after lying down, fainting or collapsing, belly that looks swollen or tight, and trouble breathing. Any of these means you need in-person emergency care immediately. Do not wait for a video call.

Do not give your dog any human heart medication, aspirin, or over-the-counter pain relievers. These can be toxic or can dangerously lower blood pressure. Do not start any supplement, including fish oil or taurine, without asking your vet first. Some supplements interact with heart drugs. Do not restrict your dog's water unless your vet tells you to. Do not stop your dog's exercise suddenly, but do avoid intense play, long runs, or heat exposure until you have a diagnosis.

What to Write Down Before You Call

A short list of notes will make your vet visit faster and more useful. Write down your dog's age, breed, and weight. Note when you first noticed the murmur, if you know. Record any coughing episodes, including how often per day and whether they happen after exercise or at rest. Note any fainting, weakness, or collapse, with dates. Track appetite and water intake. List every medication and supplement your dog takes, with doses. Mention any other health conditions, such as kidney disease or diabetes. Finally, write down your questions so you do not forget them in the exam room.

The Step-by-Step Visit and What Drives the Cost

Your vet will start with a full physical exam. They will listen to the heart on both sides of the chest, feel the pulse in the leg, check the gum color, and feel the abdomen. They will ask about the signs you have been logging. Then they will recommend tests based on your dog's age, breed, and the murmur's loudness.

The table below shows the common tests, what they do, and a general cost range. Prices vary widely by region and clinic. A specialty hospital in a city will charge more than a rural general practice. These figures are context, not quotes.

The biggest cost driver is the echocardiogram. It requires a specialist or a vet with advanced training and takes 30 to 60 minutes. If your dog is young, has a soft murmur, and shows no signs, your vet may start with X-rays and bloodwork. If your dog is older, has a loud murmur, or is already coughing, an ultrasound is often recommended early. Breed matters too. Cavalier King Charles Spaniels, Boxers, and Dobermans have specific inherited heart conditions that may warrant earlier imaging.

Questions to Ask Your Vet

Bring this list to the appointment. Ask each question out loud and write down the answers.

• What grade is the murmur, and what does that mean for my dog?
• Do you recommend an echocardiogram now, or can we monitor first?
• If we monitor, how often should we recheck?
• What specific signs should make me call you or go to the emergency room?
• Are there any activity restrictions?
• What diet or weight changes, if any, do you recommend?
• If my dog needs medication, what are the side effects and how do I give it?
• What is the expected progression for this condition?
• When should we repeat bloodwork or imaging?

When an Online Vet Can Help, and When It Cannot

Hands-on care is required for any emergency sign: difficulty breathing, collapse, fainting, blue or pale gums, or a swollen belly. A remote vet cannot listen to your dog's chest, feel the pulse, take a temperature, or run bloodwork. They cannot hear a murmur at all. If your dog shows any of those emergency signs, drive to an in-person clinic now. Do not start with a video call.

A remote consultation is genuinely useful in several situations. If your dog has a known murmur and you are wondering whether a new cough warrants a visit, an online vet can help you decide. If your dog is on heart medication and you have a question about side effects or dosing, a remote vet can advise. If your dog has a mild, previously diagnosed murmur and is due for a routine recheck, a video visit can cover history and visible signs before you decide on in-person testing. For early or mild presentations, a remote vet can explain what to watch for and help you prepare for the in-person workup.

What a remote consultation can produce: a thorough history, a look at your dog's breathing on video, advice on monitoring, and guidance on whether to seek care. In many states, a veterinarian can prescribe after a remote visit. However, prescribing rules differ by state, and many veterinarians will require an in-person examination before prescribing heart medication. That is a safety measure, not an inconvenience. Heart drugs affect blood pressure and kidney function, and dosing must be based on an actual examination and bloodwork. Your vet must determine the dose for your specific dog.

Use remote care as a triage tool and a follow-up aid, not as a substitute for diagnosis. The murmur itself can only be evaluated in person. The American Veterinary Medical Association and the American Animal Hospital Association both emphasize that a physical examination is the foundation of heart care. Plan your in-person visit, use remote help to prepare for it, and keep your daily log going until then.

Common Mistakes Owners Make With a Heart Murmur

The most common mistake is assuming a murmur is either a death sentence or nothing to worry about. Neither is true. A murmur is a finding, not a diagnosis. It tells your vet that blood flow in the heart is turbulent, but it does not say why or how serious it is.

Another frequent error is waiting for visible signs before acting. Dogs hide heart disease well. By the time you notice coughing, fatigue, or a swollen belly, the condition may be advanced. That is why a murmur found on a routine exam is a gift. It gives you time.

Some owners stop exercise entirely, thinking rest protects the heart. Sudden inactivity can weaken muscles and worsen quality of life. Others push their dog harder, hoping to "toughen it up." Both extremes are wrong. Your vet will tell you the right activity level based on the cause and stage of disease.

Finally, do not skip follow-up visits because your dog seems fine. Heart conditions change slowly. Regular rechecks catch those changes early, when treatment adjustments are easiest.

How to Reduce the Chance of It Happening Again

You cannot always prevent heart disease. Some causes are genetic, such as mitral valve disease in Cavalier King Charles Spaniels or cardiomyopathy in Boxers and Dobermans. But you can slow progression and catch problems early.

Keep your dog at a healthy weight. Extra fat makes the heart work harder. Feed a balanced diet and measure portions. Ask your vet about dental care too. Dental disease allows bacteria to enter the bloodstream, which can infect heart valves. Routine cleanings are part of heart health.

Schedule annual exams, or twice yearly for senior dogs. The American Animal Hospital Association recommends more frequent assessments for older pets because age-related disease develops quietly. Your vet can hear a murmur long before you see symptoms.

If your dog is diagnosed with a heart condition, give medications exactly as prescribed. Do not skip doses or stop early because the dog seems better. Set phone alarms if needed. Consistency matters more than perfection.

What Recovery and Ongoing Management Usually Look Like

Recovery depends entirely on the cause. A puppy with a harmless flow murmur may need no treatment at all. The murmur often disappears by six months of age. A dog with early mitral valve disease may need only monitoring for years. A dog in heart failure needs daily medication and frequent rechecks.

There is no cure for most structural heart disease. Management is the goal. That means slowing progression, controlling signs, and maintaining quality of life. Many dogs live happily for years after diagnosis. The timeline varies from months to many years depending on the condition and how early it is caught.

After the initial workup, your vet will set a recheck plan. This often means an exam every three to six months. Some dogs need repeat chest X-rays or echocardiograms to track changes. Blood tests may monitor medication side effects.

At home, you will learn to count your dog's resting breathing rate. Do this when your dog is asleep. Count breaths for 15 seconds and multiply by four. A normal rate is usually under 30 breaths per minute. Write it down daily. If the rate climbs steadily or your dog starts breathing faster at rest, call your vet. This is often the first sign that medication needs adjusting.

Frequently Asked Questions

Can a heart murmur go away on its own?

Yes, in some cases. Puppies can have innocent flow murmurs that resolve by adulthood. These are soft murmurs with no underlying structural problem. Anemia, fever, or stress can also cause temporary murmurs that disappear once the cause resolves. However, most murmurs in adult dogs are caused by structural changes in the heart and will not go away. Your vet uses the physical exam and tests to tell the difference. If the murmur is from disease, it may stay stable for years or slowly get louder as the condition progresses.

Will my dog need to see a cardiologist?

Not always. Many general practice vets are comfortable diagnosing and managing common heart conditions. They can perform chest X-rays, blood pressure checks, and basic echocardiograms. Your vet may refer you to a cardiologist if the case is complex, if the murmur is unusually loud, if your dog is young with a suspected congenital defect, or if the heart is not responding to treatment. A cardiologist has advanced imaging and more experience with tricky cases. Referral is not a sign of failure. It is a sign your vet wants the best information.

How often does my dog need a recheck?

Most dogs with a heart murmur need a recheck every three to six months. The exact interval depends on the cause, the stage of disease, and the medications your dog takes. A dog with a mild murmur and no heart enlargement may go six months between visits. A dog in heart failure may need monthly checks. Your vet will give you a specific schedule. Do not stretch the interval without asking. Early detection of worsening is the single best tool for adjusting treatment.

Can I still walk my dog?

Usually yes, but the intensity matters. Most dogs with a murmur can enjoy moderate, steady walks. Avoid strenuous exercise like long runs, fetch marathons, or agility training unless your vet clears it. Watch your dog during activity. If they lag behind, cough, pant heavily, or collapse, stop and rest. Let your dog set the pace. Your vet will give specific guidance based on the cause of the murmur and the results of your dog's tests.

What happens if I cannot afford the tests?

Tell your vet honestly. They can prioritize the most essential tests and delay others. A physical exam, chest X-ray, and blood pressure check are often the minimum needed to assess risk. Some clinics offer payment plans or work with third-party financing. Pet insurance may cover diagnostics if you enrolled before the murmur was found. Do not skip testing entirely. Knowing the cause and stage lets you make informed decisions about care and costs.

Is a heart murmur painful?

The murmur itself is not painful. It is a sound, not a sensation. However, the underlying heart disease can cause discomfort. Dogs with heart failure may feel breathless, tired, or have a swollen abdomen. These signs are distressing. Medication and monitoring are designed to relieve them. If your dog seems uncomfortable, restless, or is breathing hard at rest, contact your vet promptly. That is a sign the current treatment plan needs adjustment.

Related Clinical & Scientific Guides

• How to Help Your Senior Cat with Mobility Issues: Tips and Products
• How to Prepare Your Cat for a Vet Visit for Kidney Disease
• What Blood Tests Does My Senior Dog Need and What Do They Cost?

References and Further Reading

• AAHA Senior Care Guidelines for Dogs and Cats
• International Renal Interest Society Staging Guidelines
• AVMA Pet Owner Resources
• MSD Veterinary Manual Pet Owner Version
• AAHA Pet Owner Resources

Related Articles

• How to Prepare Your Dog for a Veterinary Visit for Arthritis
• Dog Heart Disease: How to Monitor Your Dog's Condition at Home
• How to Adjust Your Dog's Diet for Kidney Disease: A Vet's Guide
• Dog Cushing's Disease: What to Expect from Diagnosis to Daily Management
• How to Monitor Your Senior Dog's Heart Rate at Home

This article is general educational information for pet owners. It is not a substitute for veterinary diagnosis, examination, or treatment. If your pet is showing severe or rapidly worsening signs, contact an emergency veterinary hospital immediately.