Dog Heart Health: A Veterinary Cardiologist’s Guide
Heart disease is common in dogs, especially as they age, but many heart conditions can be managed for a long time when they are found early. With good care, plenty of dogs with heart conditions live happy, comfortable lives for years. Knowing your dog's normal dog heart rate is the simplest place to start. Heart checks are one pillar of caring for an aging dog – our senior dog care guide covers the rest. This guide, reviewed by a board-certified veterinary cardiologist, explains the warning signs to watch for, the main heart conditions dogs develop, how veterinarians diagnose them, and the everyday steps that support a healthy heart.
Quick answer
The most useful early warning signs are a new cough, faster breathing at rest, tiring more easily, fainting or collapse, and a swollen belly. If your dog’s resting or sleeping breathing rate is consistently over about 30 breaths per minute, or the trend keeps climbing, call your veterinarian. Labored breathing, collapse, or pale, grey, or bluish gums should be treated as an emergency.
The warning signs of heart trouble in dogs
The earliest sign is often something subtle. See your veterinarian if you notice:
- A cough, especially at night or after lying down
- Faster or harder breathing at rest (a resting/sleeping breathing rate over about 30 breaths per minute is a red flag)
- Tiring easily or not keeping up on walks
- Fainting, collapse, or sudden weakness
- A swollen or bloated belly
- Restlessness at night, or pale/bluish gums (urgent)
The main heart conditions in dogs
| Condition | What it is |
|---|---|
| Heart murmur | An extra heart sound from turbulent blood flow – a sign, not a disease itself. Read more |
| Mitral valve disease (MVD) | The most common acquired heart disease, especially in small breeds; a leaky valve that can lead to heart failure. |
| Dilated cardiomyopathy (DCM) | The heart enlarges and the muscle weakens; some cases are linked to diet/taurine. Read more |
| Congestive heart failure (CHF) | When a diseased heart can’t keep up and fluid backs up, often into the lungs. Read more |
How vets diagnose heart disease
Your veterinarian starts by listening to the heart with a stethoscope (this is how murmurs are found). From there they may recommend chest x-rays (to see heart size and lung fluid), an echocardiogram (an ultrasound of the heart – the gold standard), an ECG for rhythm, blood pressure, and sometimes a blood test called NT-proBNP that can support the picture when heart disease is suspected, though it does not replace imaging. A board-certified cardiologist can pull these together to stage the disease precisely.
How heart disease is managed
Treatment depends on the condition and stage, and is directed by your veterinarian. It can include heart medications (such as pimobendan and diuretics), a heart-friendly diet (often lower in sodium), weight management, sensible exercise, and at-home monitoring of the resting breathing rate. Nutrition can support normal heart function, but it does not replace a diagnosis or prescribed medication.
The role of diet and supplements
Good nutrition supports a healthy heart. Taurine, L-carnitine, coenzyme Q10, L-arginine, and omega-3 fatty acids all have roles in normal heart function – which is why our CardioChew, formulated with veterinary cardiologist Dr. Matthew Miller, combines them to support normal heart and circulatory function. A supplement supports a healthy heart; it does not treat heart disease and is not a substitute for veterinary care. See our guides to taurine for dogs, heart supplements, and a heart-healthy diet.
When to see your veterinarian
Book a visit for any of the warning signs above, and treat fast or labored breathing, collapse, or blue/pale gums as an emergency. Routine check-ups matter too: many heart problems are first caught as a murmur during a wellness exam, long before a dog seems sick.
Explore the guide
Start with the topic that fits your dog: heart murmurs, congestive heart failure, enlarged heart and DCM, normal heart rate, taurine, and heart supplements.
References and further reading
- American College of Veterinary Internal Medicine (ACVIM). 2019 consensus guidelines for the diagnosis and treatment of myxomatous mitral valve disease in dogs. Journal of Veterinary Internal Medicine.
- Merck Veterinary Manual (MSD Manual). Heart disease and heart failure in dogs.
- Cornell University, Riney Canine Health Center. Canine heart health resources.
Frequently asked questions
What are the first signs of heart disease in dogs?
Often a cough, faster or harder breathing at rest, tiring easily, or reduced stamina. A resting breathing rate consistently over about 30 breaths per minute is an early warning worth a vet visit.
How long can a dog live with heart disease?
It varies widely by condition and stage. Many dogs with early disease live normal lifespans; even after heart failure begins, treatment often gives dogs a good quality of life for months to a couple of years. Your vet can give your dog’s outlook.
Can heart disease in dogs be cured?
Most canine heart disease is managed rather than cured, but good treatment can keep dogs comfortable and active for a long time. Early diagnosis makes a real difference.
What can I give my dog to support heart health?
A complete balanced diet, a healthy weight, and the heart-support nutrients your vet approves. Supplements like taurine, CoQ10, and L-carnitine may support normal heart function alongside – never instead of – veterinary care.
When is a dog’s heart problem an emergency rather than a vet appointment?
Treat labored or open-mouth breathing, collapse, fainting, or blue or grey gums as an emergency and go to a clinic right away. A new cough, tiring more easily, a rising resting breathing rate, or a murmur found at a checkup means book a prompt vet visit, not an emergency.
How do I count my dog’s resting breathing rate at home?
Count the breaths your dog takes in one minute while calm or asleep. Under about 30 is reassuring, and a rate that keeps climbing above 30 to 40 is worth a vet call. See our heart rate guide for how to do it.
This guide is educational and is not a substitute for veterinary diagnosis or care. If you are worried about your dog’s heart, contact your veterinarian.
This guide is educational and is not a substitute for veterinary diagnosis or care. If your dog has signs of heart trouble, talk to your veterinarian.