Quick orientation
Heart disease is common in UK dogs — affecting roughly 10% overall and rising sharply with age. The two most common forms are mitral valve disease (small breeds, common from middle age onwards) and dilated cardiomyopathy (larger breeds, often Dobermans and similar). Both are progressive but, with modern treatment, dogs typically live for years after diagnosis with good quality of life. Early detection meaningfully extends both lifespan and quality of life.
The two main types of canine heart disease
Mitral valve disease (MVD) — the small-breed condition
The most common heart condition in UK dogs. The mitral valve (between the left atrium and left ventricle) gradually thickens and stops sealing properly, causing blood to leak backwards. The heart compensates by enlarging. Eventually, if untreated, the changes lead to congestive heart failure.
Strongly linked to small and toy breeds: Cavalier King Charles Spaniels are particularly affected (often from middle age), but Chihuahuas, Yorkshire Terriers, Dachshunds, and many other small breeds are over-represented. Most cases are diagnosed by middle age and progress over years.
Dilated cardiomyopathy (DCM) — the large-breed condition
The heart muscle weakens and the heart enlarges, losing its ability to pump effectively. Usually affects larger breeds: Dobermans (particularly), Boxers, Great Danes, Irish Wolfhounds, and (more recently in the UK) some Cocker Spaniels. Often progresses faster than MVD; in some breeds it can present suddenly with collapse or sudden death.
Additionally there are congenital heart defects (present from birth, often diagnosed in puppies during early checks), arrhythmias (irregular heart rhythm, sometimes linked to specific breeds like Boxers), and pericardial disease (uncommon).
Have some form of heart disease
Develop mitral valve disease
Typical lifespan after diagnosis with treatment
Typical UK echocardiogram cost
Warning signs to watch for
The early stages of heart disease are usually silent — the dog seems entirely well, and the only sign is a heart murmur picked up during routine veterinary examination. This is one of the strongest arguments for annual or twice-yearly check-ups, particularly for at-risk breeds.
As the disease progresses, signs to watch for:
- Coughing, particularly a dry cough that gets worse with exercise or at night, or after lying down
- Reduced exercise tolerance — needing to stop on walks they used to manage
- Faster breathing rate at rest — healthy dogs typically breathe 15–30 breaths per minute when sleeping; consistently above 30 warrants attention
- Lethargy or sleeping more
- Reduced appetite
- Episodes of fainting or collapse, often after exercise or excitement (a more serious sign)
- Restlessness at night, difficulty getting comfortable
- A swollen abdomen in advanced cases
- Pale or bluish gums in severe acute episodes (emergency)
Monitoring resting respiratory rate at home is one of the single most useful things owners can do for a dog with known heart disease. Count breaths over a minute while the dog is asleep — a sustained increase above 30 (or above the dog's own established baseline) is the earliest warning of fluid building up in the lungs and warrants prompt vet contact.
Sudden severe breathing difficulty is an emergency
A dog with known heart disease who suddenly develops rapid, laboured breathing, can't settle, or has pale or bluish gums is having a likely cardiac emergency. Contact a vet immediately or take the dog directly to an emergency clinic — see our emergency vet guide for more on recognising urgent situations. Early treatment of acute heart failure markedly improves outcomes.
What diagnosis involves
A typical UK cardiac workup:
- Clinical examination — the vet will listen carefully to the heart and lungs, check pulse quality, examine gum colour and refill time. A new murmur in an at-risk breed is the most common starting point.
- Chest X-rays — assess heart size, look for fluid in or around the lungs.
- Echocardiogram (heart ultrasound) — the most informative test. Shows valve function, chamber sizes, and pumping efficiency. Increasingly performed in general practice with cardiology training; advanced cases may be referred to a cardiology specialist.
- ECG — useful when arrhythmias are suspected.
- Blood tests including NT-proBNP — a heart-specific marker that can help stage disease and monitor response to treatment.
- Blood pressure measurement
For confirmed serious disease, periodic re-staging is typical: every 6–12 months in stable cases, more frequently if symptoms change.
Treatment
Treatment depends on the type and stage. For the most common pattern (advanced mitral valve disease):
- Pimobendan — the cornerstone medication for symptomatic MVD and DCM. Improves heart function and survival. Recent UK and international evidence supports starting it earlier than was previously practice in some pre-symptomatic dogs with significant heart enlargement.
- Diuretics (typically furosemide) — to manage fluid build-up once heart failure develops
- ACE inhibitors — added at certain stages to reduce strain on the heart
- Spironolactone — often added in advanced cases
Dietary management (controlled sodium, sometimes a prescription cardiac diet) supports medication. Exercise should be moderated based on the dog's tolerance — not stopped, but not pushed.
For DCM in specific breeds, the medication regime is broadly similar but the prognosis varies more widely by breed.
For selected mitral valve disease cases, surgical mitral valve repair is now available at a small number of UK referral centres. It's a major procedure with a substantial cost (typically £15,000–£25,000+) but offers a curative option for selected dogs. Discuss with a cardiologist whether it might be appropriate.
Typical UK costs in 2026
- Initial consultation + auscultation: £35–£70
- Chest X-rays: £150–£300
- Echocardiogram (general practice): £300–£600
- Echocardiogram (specialist cardiologist): £500–£900
- NT-proBNP blood test: £100–£180
- Pimobendan + furosemide combination (varies by dog size): £50–£180/month
- Routine quarterly review + bloods: £120–£250
Most lifetime pet insurance policies cover cardiac disease. Check whether your policy has annual condition caps, whether echocardiograms count as diagnostics or treatment, and (if relevant) whether surgical mitral valve repair would be covered.
Choosing a vet for cardiac care
Most UK general practices manage stable heart disease competently. For more complex cases or specific breeds, things to look for:
- A vet with additional qualifications or particular interest in cardiology
- In-house echocardiography or a clear, fast referral pathway to a cardiologist
- For at-risk breeds (Cavaliers, Dobermans, Boxers), a practice that takes routine cardiac screening seriously — ideally annual auscultation in middle age, with formal echocardiogram screening as appropriate
- For dogs with established heart disease, a practice that supports home respiratory rate monitoring and is responsive when those numbers shift
Our choosing a vet guide covers the general framework.
Frequently asked questions
Find a vet for ongoing cardiac care
Cardiac care is a long-term relationship with one practice. The FetchRated directory lists UK veterinary practices with verified reviews — use it to find a practice with strong cardiology experience for ongoing care.
