Heart Disease in Dogs
Overview/Description of Disease
The heart is a muscular pump which pushes blood around the entire body. In a normal dog it beats approximately 150,000 times a day. A muscle that works this hard needs to be in shape (with good muscle tone) to do its job effectively!
The heart is actually made up of two pumps because a dog's body, like ours, has two different circuits for blood flow, moving first through one and then the other. One of these circuits takes blood through the lungs so that oxygen can be replenished and waste gases, such as carbon dioxide, are removed. This oxygen-enriched blood then moves through the other circuit, reaching all parts of the body to deliver the oxygen needed for normal body function and removing waste products as needed.
Heart disease causes a disruption in circulation; blood is pumped less effectively, leading to poor blood supply to muscles and organs. Because muscles and organs need consistent blood supply to work correctly and stay healthy, heart disease can cause muscles and organs to atrophy and weaken.
There are several forms of heart disease that affect dogs, some of which affect the heart muscle itself and others which affect the heart valves. One of the most common forms of heart disease is dilated cardiomyopathy. Another common form is chronic valve disease (CVD).
Dogs are often at risk for certain types of heart disease depending on genetics, breed, age, and size. Breeds commonly affected include:
- Doberman Pinschers
- Cocker Spaniels
- Great Danes
- Irish Wolfhounds
- Boston Terriers
While a dog's body is resilient and is able to adapt to heart disease early on, as the disease progresses, the heart's ability to function becomes so poor that symptoms of failure become easier to spot. Keep an eye on your pooch and make sure to call your veterinarian if he or she:
- Doesn't want to play or exercise
- Is tired or lethargic
- Has difficulty breathing or is coughing up fluid
- Collapses or faints
Diagnosis and Treatment
Valve disease is usually first identified when your veterinarian hears a murmur, caused because the valve has become leaky. Cardiomyopathy (heart muscle disease) may or may not cause a murmur so there may be no immediate signs for your veterinarian to identify. If they suspect heart disease, either because they hear a murmur or they are suspicious based on what you tell them, your veterinarian