Understanding heart failure in dogs
Causes, Symptoms and Long-Term Management
This article is for educational purposes only and does not promote or advertise prescription-only veterinary medicines. Any treatment discussed should only be used under veterinary direction and supplied against a valid veterinary prescription where required.
Heart failure in dogs is a condition where the heart can no longer pump blood as efficiently as the body requires. This does not mean the heart has stopped working, but that it is struggling to meet the body’s demands.
How a normal heart pumps blood around the body:
Heart failure usually develops as a result of underlying heart disease. With appropriate veterinary management and monitoring, many dogs can live comfortably for months or even years after diagnosis.
What causes heart failure in dogs?
- Mitral valve disease – common in small and medium breeds
- Dilated cardiomyopathy (DCM) – more common in large breeds
- Congenital heart defects
- Chronic heart rhythm abnormalities
What happens in heart failure?
As the heart weakens, pressure builds within the circulation. This can lead to fluid accumulation in the lungs or abdomen, resulting in breathing difficulty and reduced exercise tolerance.
The body activates compensatory hormonal systems to support circulation, but over time these changes contribute to disease progression. Many veterinary treatments aim to counteract these effects.
Common signs of heart failure in dogs
- Coughing (especially at night)
- Reduced exercise tolerance
- Increased breathing effort
- Lethargy
- Abdominal swelling
- Collapse in advanced cases
How heart failure is managed
Heart failure cannot usually be cured, but it can often be managed effectively. Treatment plans are tailored to the individual patient and adjusted over time.
Management typically involves medications that:
- Support cardiac output
- Reduce fluid accumulation
- Modulate hormonal pathways involved in disease progression
Common medication classes used in canine heart disease
Pimobendan (inodilator therapy)
Pimobendan is commonly used to support heart function. It increases contractility while reducing vascular resistance, helping improve circulation efficiency.
It may be used in dogs with mitral valve disease or dilated cardiomyopathy based on veterinary assessment.
Diuretics
Diuretics help remove excess fluid from the body and are used when fluid accumulation occurs in the lungs or abdomen.
Different diuretic options may be selected depending on clinical response and disease progression.
RAAS-modulating medications
Medications acting on the renin-angiotensin-aldosterone system (RAAS), including ACE inhibitors and related drugs, are used to reduce cardiac workload and counteract harmful hormonal effects.
Living with a dog with heart failure
Many dogs maintain a good quality of life with appropriate treatment and monitoring. Owners play a key role in ongoing care.
- Administer medication consistently
- Monitor resting breathing rate
- Watch for changes in behaviour or appetite
- Seek veterinary advice if symptoms change
Monitoring resting respiratory rate at home
Digital monitoring tools
Some owners prefer digital tools to track trends over time. Apps can help record respiratory rate and share data with veterinary professionals where needed.
Prescription medicines and veterinary oversight
Many medications used in heart disease are classified as prescription-only veterinary medicines (POM-V).
These medicines require a valid prescription and ongoing veterinary supervision to ensure safe and effective use.
Accessing ongoing treatment
If your dog has been prescribed long-term medication, your veterinary surgeon may provide a written prescription for ongoing supply through a registered veterinary pharmacy.
Supporting long-term heart care
A diagnosis of heart failure can feel overwhelming, but many dogs respond well to treatment. Understanding the condition and maintaining consistent monitoring helps support long-term management.
Your veterinary team can guide treatment decisions and adjust therapy as needed over time.