Heart Disease in Cats: UK Guide to Symptoms and Treatment
Heart disease is less discussed in cats than in dogs, but it is far from rare — hypertrophic cardiomyopathy (HCM) alone affects an estimated one in seven cats at some point in their lives. Because cats are masters at hiding illness, heart disease often goes undetected until it has progressed to a dangerous stage. Knowing the signs and getting regular screening can make a real difference.
Key takeaways
- HCM is the most common feline heart disease — many cats are diagnosed only after a routine murmur detection, underlining the value of regular check-ups.
- Echocardiography (£300–£600) is the definitive diagnostic tool; ongoing medication typically costs £20–£60 per month.
- A cat breathing rapidly at rest or open-mouth breathing is a potential cardiac emergency — seek veterinary help immediately.
Types of Heart Disease in Cats
The most common feline heart disease by a considerable margin is hypertrophic cardiomyopathy (HCM), in which the walls of the heart muscle thicken, reducing the heart's ability to fill and pump blood effectively. It can be inherited (particularly in Maine Coons, Ragdolls, British Shorthairs and Persians) or develop spontaneously in any breed.
Other types include dilated cardiomyopathy (DCM), where the heart muscle becomes thin and weak — once common due to dietary taurine deficiency, now rare in cats fed complete diets — and restrictive cardiomyopathy, where scar tissue stiffens the heart. Secondary heart disease can result from hyperthyroidism (common in older cats) or high blood pressure causing the heart to thicken in response to increased workload. Treating the underlying cause can improve or stabilise the cardiac changes in these secondary cases.
Signs of Heart Disease in Cats
Many cats with HCM remain asymptomatic for years and the condition is only detected by a vet hearing a heart murmur during a routine check-up. When symptoms do appear, they can include rapid or laboured breathing, open-mouth breathing, lethargy, collapse and reduced exercise tolerance. Some owners notice their cat breathing faster during sleep — counting resting respiratory rate (normal is under 30 breaths per minute) is a useful home monitoring tool recommended by cardiologists.
Congestive heart failure (CHF) occurs when the failing heart causes fluid to accumulate in the chest (pleural effusion) or lungs (pulmonary oedema). This is a genuine emergency: a cat in respiratory distress — struggling to breathe, gaping mouth, blue-tinged gums — needs immediate veterinary attention. A particularly devastating complication is aortic thromboembolism (ATE or 'saddle thrombus'), where a clot lodges at the aortic bifurcation, causing sudden paralysis of the hindlimbs and severe pain.
Diagnosis and Costs
If your vet detects a heart murmur or suspects cardiac disease, they will recommend an echocardiogram (cardiac ultrasound) — the gold standard for diagnosing and staging HCM. This typically costs £300–£600 at a general practice, or slightly more if performed by a veterinary cardiologist. Chest X-rays (£100–£250) help detect fluid accumulation, and an ECG (£60–£120) may be recommended to assess heart rhythm.
BNP (BNP/NT-proBNP) blood tests (£40–£80) can support diagnosis by indicating heart muscle stress, though they do not replace imaging. For cats with known HCM, annual or six-monthly echocardiograms are recommended to monitor progression. Genetic testing for HCM mutations in predisposed breeds (Maine Coon, Ragdoll) costs around £50–£100 through specialist laboratories and is valuable for breeding decisions.
Treatment and Managing Heart Disease in Cats
Treatment depends on the stage of disease. Asymptomatic HCM — especially with only mild to moderate changes — may not require medication initially. Once the cat progresses to a more advanced stage, medications are introduced. Atenolol (a beta-blocker) or diltiazem (a calcium channel blocker) may be used to slow the heart rate, and clopidogrel (an antiplatelet drug) is often prescribed to reduce the risk of dangerous blood clot formation.
For cats in congestive heart failure, diuretics such as furosemide are essential — and injectable furosemide in an emergency visit costs as part of an overall treatment that may reach £500–£1,500 including hospitalisation and drainage of pleural fluid. Long-term oral medication typically costs £20–£60 per month. Cats that survive a saddle thrombus episode require intensive care costing £1,000–£3,000 and have a guarded prognosis for recurrence. Regular home monitoring of resting respiratory rate is strongly recommended by the VRCC (Veterinary Referral and Critical Care) and other UK cardiologists.
Find a Vet Near You
Heart disease management involves specialist tests and ongoing monitoring. Use CompareMyVet at app.comparemyvet.uk to find local practices with published prices so you can plan your cat's cardiac care without financial surprises.
Related guides
Common questions
Many cats with asymptomatic or mild HCM live years without medication and maintain a good quality of life. Once congestive heart failure develops, prognosis shortens but cats can still have months of comfortable life with appropriate treatment and careful home monitoring.
Yes — breeds such as Maine Coons, Ragdolls and British Shorthairs are at higher risk, and echocardiographic screening every one to two years from around two years of age is recommended by veterinary cardiologists. Early detection allows closer monitoring and timely intervention.
HCM has a hereditary component, particularly in Maine Coons and Ragdolls where specific gene mutations (MYBPC3) have been identified. DNA tests can detect these mutations, though a negative test does not rule out HCM from other causes.
CompareMyVet is live in Brighton & Hove — search 29 practices by price, ownership and services. Launching across the UK in 2026.