Your pet’s heart is one of their most important organs, despite its simple design—four chambers that receive and pump blood, and four valves that keep blood flowing in the correct direction. A number of problems can disrupt normal function, however, and heart disease affects approximately 15% of cats and 10% of dogs, which means the condition is fairly common. Unfortunately, heart disease is often silent until it progresses and compromises your pet’s health. A 2015 study published in the Journal of Veterinary Cardiology found that heart disease was common in apparently healthy cats. The Mill Creek Animal Hospital team does not want your pet’s health to suffer, so we are reviewing heart disease basics, including how to detect a problem in your pet early, before the disease advances.

Common heart disease types in pets

Pets do not develop atherosclerosis and have heart attacks like people, but several heart disease types are common, including:

  • Hypertrophic cardiomyopathy (HCM) — HCM, the most common heart disease to affect cats, causes the heart wall to thicken inward, which shrinks heart chamber size. The smaller chambers do not keep up with normal blood flow, and blood backs up in the cat’s lungs. Sluggish blood flow can also cause formation of a clot (i.e., aortic thromboembolism), which can break free from the heart, become lodged in the vessels leading to the back legs, and obstruct blood flow.
  • Valvular disease — Valvular degeneration, which interferes with normal blood flow through the heart, is the most common heart disease in dogs. A damaged heart valve does not completely close and allows blood to backflow, or regurgitate, when the heart contracts. Valvular degeneration most commonly affects older, small-breed dogs.
  • Dilated cardiomyopathy (DCM) — DCM, which develops mainly in dogs, causes the heart wall to weaken and stretch. Over time, pressure causes the heart chambers to dilate, and the weakened walls cannot adequately pump blood to the body. DCM mainly develops in genetically predisposed dog breeds, but a recent increase in cases has been potentially linked to boutique, exotic, and grain-free (BEG) diets.
  • Heartworm disease — Heartworms are parasitic worms transmitted by mosquitoes. As the microscopic larvae mature, they migrate to the heart and lungs, causing inflammation and obstructing blood flow. Infections will progress and become life-threatening without treatment.
  • Congestive heart failure (CHF) — Any heart disease that slows blood flow through the heart, such as HCM or DCM, can cause CHF. As blood backs up in vessels leading to the heart, excess pressure causes fluid to leak into the lungs, thorax, or abdomen. 

Heart disease signs in pets

Heart disease often causes few obvious signs, making regular veterinary visits critical for your pet. During a thorough physical exam, our veterinary team can often detect subtle signs that indicate a problem. 

As heart disease advances, your pet may develop more obvious clinical signs, such as:

  • Lethargy
  • Tiring easily
  • Decreased appetite
  • Coughing
  • Difficulty breathing

If your pet shows heart disease signs, our team should evaluate them immediately. 

Heart disease diagnosis in pets

During your pet’s physical exam, our veterinary team will look for signs, such as an increased respiratory rate, heart murmur, or pale mucous membranes, that could indicate heart disease. If we suspect a problem, we may perform additional diagnostic tests, such as:

  • Blood pressure measurement
  • Blood work
  • Chest X-rays
  • Electrocardiogram (ECG)
  • Cardiac ultrasound

Heart disease treatment in pets

Many heart disease types can be treated to allow your pet to enjoy a good quality of life. Medications are often used to improve the heart’s efficiency, so it can better keep up with your pet’s oxygen needs. If your pet develops CHF, medication may also be used to control fluid accumulation. Heart disease treatment will include frequent veterinary visits to monitor your pet’s progress and heart function. 

Heart disease prognosis in pets

Your pet’s long-term prognosis depends on their heart disease type and severity. Treatment success and prognosis is typically better in pets who are diagnosed early, before their heart disease advances. Unfortunately, DCM that develops naturally carries a poor prognosis and typically progresses to death. DCM that develops secondary to a BEG diet may resolve with a diet change.

Heart disease prevention in pets

While you cannot prevent every heart disease type, you can take measures to significantly decrease your pet’s risk. Institute these precautions to keep your pet healthy:

  • Ensure your pet is on year-round heartworm prevention—ask our team which product is best for your pet’s situation.
  • Feed your pet a veterinary-approved diet that includes on the packaging an American Association of Feed Control Officials (AAFCO) guarantee that the diet meets specific veterinary standards. 
  • Keep your pet at a healthy weight. Like people, overweight pets are more likely to develop heart disease, and excess weight can worsen existing disease.

Routine veterinary visits are critical to detect heart disease signs, and any other potential problems, before they progress. Contact us at Mill Creek Animal Hospital to schedule your pet’s next check-up, so you can get ahead of any problems they may develop.