Quick answer

The earliest signs of heart disease in dogs are a soft cough (especially at night or after lying down), tiring faster on walks, and a resting breathing rate above 30 breaths per minute while asleep. If you notice any of these, schedule a vet visit — early detection can significantly improve outcomes.

What are the first signs of heart problems in a dog?

Heart disease often starts quietly. Watch for: a soft, persistent cough — especially at night or after resting; tiring faster on walks; faster breathing while asleep; restlessness at night; and in later stages, a swollen belly or fainting. Any fainting or collapse is an emergency — go to a vet immediately.

How do I check my dog’s resting breathing rate?

While your dog is fully asleep, count one full rise-and-fall of the chest as one breath. Count for 30 seconds and double it. Under 30 breaths per minute is generally normal. Consistently above 30 — or a noticeable upward trend — is worth mentioning to your vet. Our homepage has a free tap-along counter that does the timing for you.

Which breeds are more prone to heart disease?

What happens at the vet?

Your vet will listen for a heart murmur, may recommend chest X-rays and blood work, and might refer you to a specialist for an echocardiogram (ultrasound of the heart). The key is staging — determining where things are so the right plan can start at the right time.

How can I support a dog with a heart condition?

Follow any prescribed medication schedule closely, keep their weight healthy, stick to consistent moderate exercise, and monitor their sleeping breathing rate regularly. Talk to your vet about diet — and don’t hesitate to ask for a referral to a specialist if you want a second opinion.

This article is for general information and is not a substitute for veterinary advice.

Not veterinary advice This article is for general educational purposes only. We are dog owners who research carefully — we are not veterinarians. Nothing here is a substitute for professional veterinary advice, diagnosis, or treatment. Always consult your veterinarian about your dog's specific situation, and never delay seeking veterinary care because of something you read online. See our full Disclaimer.
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