The heart rarely gets the credit it deserves—steadily beating away for the duration of our pets’ lives. The heart seems only to attract our attention when it’s abnormal—when it skips a beat, races, flutters, or stops. University Veterinary Hospital wants to help you learn about common pet heart diseases, so that you never take a single beat of their heart, or yours, for granted.

What is heart disease in pets?

Heart disease is any abnormality of the heart or its function and includes many conditions. Heart disease affects 10 percent of dogs, and 15 percent of cats—equating to roughly 7.8 million dogs and 12 million cats. This sizable problem is especially sinister, because most pet heart disease goes unnoticed until the condition is severe. 

Common heart diseases in pets

Fortunately, dogs and cats do not suffer from myocardial infarction (i.e., heart attack). However, they are susceptible to other conditions that damage the heart’s ability to provide necessary blood flow to the body, including:

  • Valvular disease (i.e., mitral and tricuspid regurgitation) Degenerative changes to the heart valves make them “leaky,” allowing blood to flow backward. The leak weakens the heart’s contraction, forcing the heart to move a greater blood volume. The heart muscle thickens and fatigues from overuse. Valvular disease is the number one cause of heart disease in dogs, primarily affecting small breeds, starting at 8 years of age.
  • Dilated cardiomyopathy (DCM) — DCM is caused by the heart’s failure to pump effectively. Enlarged ventricles with thin walls weaken the heart’s contraction strength, and makes delivering oxygenated blood to the body difficult. DCM is the second most common heart disease in dogs, and frequently affects genetically predisposed breeds. DCM has also been linked to boutique, exotic, and grain-free (BEG) diets in many “non-traditional” DCM breeds.
  • Hypertrophic cardiomyopathy (HCM) — HCM is the most common heart disease in cats. In HCM, the left ventricle walls thicken, shrinking the chamber, and reducing the blood volume pumped to the lungs. The heart beats faster to compensate, creating an increased oxygen demand and depriving other body parts. Heart muscle cells die off at a higher rate, leading to further weakening, abnormal rhythms, and heart and lung congestion.
  • Congenital issues — Heart-related birth defects are most commonly openings between the heart chambers that fail to close before birth, or an abnormal blood flow between the heart and the lungs that does not become sealed.
  • Heartworm disease — Heartworms are parasites transmitted by infected mosquitoes. Adult heartworms live in the large pulmonary vessels and the heart, causing resistance to blood flow and forming blockages.
  • Congestive heart failure (CHF) CHF is a condition that results from any disease that slows heart flow. Congestion refers to fluid buildup, most commonly in the lungs or surrounding the heart.

Heart disease signs in pets

Heart disease may go unnoticed until visible signs appear in the advanced stages. Signs vary depending on the condition and its progression, and may include:

  • Coughing
  • Collapse
  • Trouble breathing
  • Fatigue or exercise intolerance
  • Lethargy
  • Disinterest in previously enjoyable activities
  • Abnormal hind limbs (e.g., movement, pain, or paralysis)

Heart disease diagnosis in pets

Your pet’s University Veterinary Hospital veterinarian will perform a physical examination and listen to your pet’s heart and lungs for abnormalities. If disease is suspected, further diagnostics will be recommended, such as:

  • Blood work — CBC and chemistry to evaluate overall health, and possibly a Cardiac ProBNP test, to check for cardiac biomarkers
  • Chest X-rays — To check the lungs for fluid, and assess heart size and shape
  • Electrocardiogram (ECG) To measure the heart’s electrical activity, to look for arrhythmias 
  • Echocardiogram — A heart ultrasound allows the veterinarian to evaluate the heart’s structure, blood flow, and function in real-time

Depending on your pet’s case, we may refer them to a veterinary cardiologist for management.

Heart disease treatment in pets

Medication is the primary method for treating heart conditions. The treatment goal is to improve the heart’s function by reducing its workload. Medication can lessen the heart’s workload by: 

  • Removing excess fluid
  • Decreasing blood pressure
  • Increasing heart muscle strength
  • Preventing arrhythmias

Pets with heart disease must be closely monitored by their cardiologist or veterinarian. Medication adjustment is common, especially after signs have stabilized, so rechecks are important, to ensure the most effective treatment.

Heart disease prognosis in pets

Survival times for pets with heart disease can vary. Early detection and medical management can help many pets live several years after diagnosis, but this is not guaranteed. Pets who are diagnosed with advanced disease may live for only a few months, despite aggressive treatment. 

Heart disease prevention in pets

Although heart disease cannot always be prevented, you can reduce your pet’s risks these ways:

  • Parasite prevention — Stay up-to-date with your pet’s annual preventive care. Regular examinations are key to early detection and treatment.
  • Heartworm prevention — Give your pet year-round heartworm prevention treatment, and have them tested annually for heartworm disease.
  • Quality diet — Feed your pet a high quality, grain-inclusive diet. Contact us for diet recommendations.
  • Watch for weight gain — Keep your pet at a lean body weight. Obesity increases cardiovascular workload. 

The heart certainly knows how to get our attention. Fortunately, when you are informed about heart disease, you are prepared to make wise decisions about your pet’s care. To schedule your pet’s wellness appointment, contact University Veterinary Hospital.