Heart disease is a catch-all term that describes the many possible heart conditions seen in around 10% of dogs and cats. Pets can be born with heart disease (i.e., congenital), but they more commonly acquire the disease over time. Pet heart diseases differ from people, so Neighborhood Veterinary Centers wants to provide pet owners the information they need to recognize potential heart disease signs and provide their pets with needed care.

Heart disease versus heart failure in pets

Heart disease and heart failure are two different conditions with different implications for your pet’s long- and short-term health. Heart disease is any condition or abnormality that affects the heart’s structure or function, and may or may not lead to heart failure over time. Heart failure is the heart’s inability to adequately pump blood throughout the body, which results in oxygen deprivation and failure of other organs to properly function. 

Heart failure can only result from heart disease, but not all heart diseases lead to heart failure.

Pet heart disease types

Dogs and cats can suffer from many heart diseases, including those they are born with and those they acquire with age. Different diseases cause various changes to normal heart function, including:

  • Abnormal valve closing or opening
  • Abnormal communication (i.e., holes) between heart chambers
  • Fast, slow, or irregular heart rhythm
  • Too much resistance in the blood vessels
  • Physical blockages caused by parasites (i.e., heartworm)
  • Heart muscle weakness, leading to heart enlargement

Dogs and cats are prone to different heart disease types, with 85% of cats with heart disease diagnosed with hypertrophic cardiomyopathy. Many heart disease variations exist, but the most commonly diagnosed in dogs include:

  • Mitral valve dysplasia or degeneration
  • Dilated cardiomyopathy
  • Heart arrhythmias and arrhythmogenic cardiomyopathies
  • Heartworm disease

Pet heart disease diagnosis

Heart disease is often suspected based on a routine physical examination, when your veterinarian first detects a heart murmur (i.e., an abnormal “whooshing” sound). Abnormal heart rhythms or weak, irregular pulses also indicate heart disease. Heart disease should be suspected if you or your veterinarian note any of the following signs:

  • Exercise intolerance or uncharacteristic fatigue
  • Coughing, in dogs only
  • Fainting or collapsing
  • Increased breathing effort or rate
  • Fluid accumulation in the lungs, abdomen, or legs
  • Blood pressure problems

Specific diseases may depend on your pet’s age or breed. A few well-known examples include mitral valve disease in Cavalier King Charles spaniels and arrhythmogenic cardiomyopathy in boxers. Definitive diagnosis requires specialized heart testing, including:

  • Chest X-rays — To evaluate heart size and look for fluid buildup
  • Electrocardiogram (EKG) — To evaluate heart rhythm and electrical activity
  • Heart ultrasound — To evaluate blood flow and valve function
  • Blood testing — To look for heart-damage-specific proteins

Your veterinarian may refer your pet to a veterinary cardiologist during or after their heart disease diagnosis. Specialists can often better manage your pet’s long-term heart disease care and make adjustments for optimal treatment.

Pet heart disease treatments

Heart disease treatments depend on the specific functional problem and may include:

  • Medications — Medications are used to improve blood flow and heart muscle strength, reduce fluid buildup, regulate blood pressure, normalize heart rate and rhythm, and reduce heart muscle damage.
  • Surgery — Some congenital conditions or valve disorders may respond best to surgical treatments, which are performed only by qualified veterinary cardiologists or surgeons in highly specialized facilities.
  • Heartworm treatment — A medication protocol can successfully kill heartworms in dogs but requires several months of strict rest. Cats cannot receive this medication, so they are closely monitored and given supportive care until the worms die naturally.

How long can pets with heart disease live?

Most pets with heart disease who are properly managed can live years after their diagnosis, and many pets with congenital disease who receive surgical treatments can live full, normal lives. Unfortunately, some cats with heart disease do not show disease signs until they die unexpectedly. Some pets with heart disease will progress quickly to heart failure and live only weeks or months following their diagnosis. Working closely with your veterinarian and a veterinary cardiologist will maximize your pet’s quality of life and longevity.

Heart disease in pets usually develops over time, and intervention during the early stages can greatly improve your pet’s outcome. Contact your nearest Neighborhood Veterinary Centers location to schedule a visit if you notice your pet acting tired or displaying other heart disease signs, or if your pet needs an overall health and wellness check.