With Valentine’s Day fast approaching, this is when we all make time to appreciate those that are special to us. Our pets hold a special place in our hearts, and so, we should make sure that we take care of theirs. This month’s Moss Veterinary Hospital newsletter will focus on heart disease in pets. Heart disease is not just a human problem. In animals, heart conditions can generally be divided into congenital and acquired forms; with congenital diseases being those that animals are born with and acquired conditions are those that develop during the life of the animal.

Acquired heart disease in dogs

Heart disease is not an uncommon problem among dogs and depending on breed prevalence can affect between 8-10% of the dog population with increasing incidence with age. Acquired heart disease accounts for 95% percent of the primary heart conditions.

There are two principal causes of acquired heart disease in dogs:

Valvular disease

This results from a dysfunction of the valves within the heart. Normally valves create a tight seal between the chambers of the heart that allow one-way flow of blood through the heart. Incompetent or leaking valves allow blood to flow backward within the heart chambers and create turbulence that is heard as a murmur with a stethoscope. This form of heart disease is more common within small to medium breeds. Susceptible breeds include the Cavalier King Charles Spaniel, Schnauzers, Poodles and Chihuahuas.


Dilated Cardiomyopathy (DCM)

This is the second most common form of heart disease and results from the ineffective pumping action of the muscles of the heart resulting in stretching of the heart muscles. This usually affects large to giant breed dogs

including Dobermans, Boxers, Great Danes, Irish Wolfhounds and St. Bernard’s.


Acquired heart disease in cats

Acquired disease in cats can be further categorized as either primary cardiomyopathy or secondary heart disease, which may result from such conditions as systemic hypertension and thyroid disease. Heart disease is fairly common in the cat, and animals can have the disease for many years before exhibiting any clinical signs.

Hypertrophic cardiomyopathy is the most common form of heart disease in the cat and reduced cardiac function results from an increase in the thickness in the heart muscle.


Animals will advanced heart disease will often enter a phase known as congestive heart failure (CHF) where the body is no longer able to cope with the reduced effectiveness of the heart and significant signs develop.

Cardiac arrhythmia

A cardiac arrhythmia is an irregularity in the normal rhythm of the heart beat. This may occur with or without the presence of muscular changes in the heart (cardiomyopathy) but can also have serious implications for heart function. Animals with cardiac arrhythmias may also show similar signs to those with muscular or valvular heart disease. An ECG is required to determine the nature of abnormal cardiac rhythms.

Signs of heart disease

How will you know if your pet is suffering from a heart condition?

You may notice the following in any combination.

  • Rapid or difficult breathing (especially panting in cats).
  • Coughing.
  • Changes in behavior.
  • Reluctance to exercise or tiring easily.
  • Restlessness—especially at night.
  • Poor appetite and/or weight loss.
  • Swollen abdomen.
  • Fainting/collapsing.


Here at Moss Veterinary we use a variety of methods to diagnose the presence of heart disease including thorough physical examinations and listening to your pet’s heart and lungs; but other diagnostic tools include: thoracic x-rays, cardiac ultrasound, ECG, blood tests and blood pressure measurement. Early diagnosis and treatment can help your pet to live a longer and more enjoyable life.

Ways to keep your pet healthy

Take note of any changes in your pet’s behaviour or energy levels.

o Maintain proper body weight. Avoid high fat treats or salty snacks.

o Maintain regular exercise – Ask your veterinarian about the type, level, and frequency of exercise that’s right for your pet.

o Annual checkups – taking your pet to the vet at least once a year can help to make sure any conditions are diagnosed early.

o For dogs – Know your breed! Some are more prone to heart disease.

We will be conducting special cardiac clinics during the month of February, where, if you are concerned that your pet may have symptoms of heart disease or already has a diagnosed heart condition, we will perform a physical examination of your pet’s cardiopulmonary system free of charge.  The clinics will take place on February 14th and 28th between 2 – 4pm. Please contact the clinic to book an appointment or discuss your pet’s condition with one of our staff members.