It is often said that the best things come in small packages. When it comes to a Chihuahua’s heart, this is definitely true. Although it is very small, this organ is somewhat like the engine that drives the rest of the body.
A Chihuahua’s heart works exactly like ours, only on a miniature scale. Blood flows into the right side of the heart. From there, it travels to the lungs to pick up oxygen. From the lungs, blood flows to the left side of the heart.
The left side is somewhat larger than the right and has more pressure. It pumps oxygenated blood to fuel the rest of the body. If all of this seems like a lot of work, that’s because it is. In tiny dogs, this cycle may be completed as often as 160 times every minute.
The Size of a Chihuahua’s Heart
A Chihuahua’s heart size will vary depending on how big or small the dog is. On average, it will range from the size of a grape to the size of a walnut. For comparison, a giant breed, such as an Irish wolfhound, has a heart about the size of an adult fist.
There’s actually a way to measure heart size in dogs. It’s called the vertebral heart scale. Using x-rays of the chest, veterinarians measure distances between the heart, rib bones and certain backbones. This tells them is there is something abnormal about the size of the heart, such as being too big or too small.
Knowing how the heart size stacks up against averages gives them important clues on how well it is working. The term for a heart that is too big is cardiomegaly. Diseases or conditions that cause cardiomegaly are called cardiomyopathies.
Diseases That Affect Chihuahua Hearts
Like many toy breeds, Chihuahuas inherit an increased risk for developing heart defects. The most common defect seen in this breed is called patent ductus arteriosus.
Before puppies are born, their lungs don’t work. Blood is oxygenated through the mother’s placenta. It bypasses the puppy’s lungs completely. This is done by a blood vessel called the ductus arteriosus.
This blood vessel normally closes at birth. At that time, blood can begin circulating through the lungs normally. Sometimes, this vessel doesn’t close as it should. This eventually causes heart failure, although most puppies appear healthy at diagnosis.
Chihuahuas pass this common defect through breeding. The good news is that it can be corrected with surgery if it is caught soon enough.
Other conditions that affect a Chihuahua’s heart include swelling, infection, leaking valves and abnormal rhythms. Most of these conditions are treatable with medication, diet and exercise.
Keeping a Chihuahua’s Heart Healthy
The principles of keeping a Chihuahua’s heart healthy aren’t that different from those for humans. Keeping weight in check, regular exercise and a good quality diet go a long way towards helping this amazing organ stay in tip-top condition.
Most people are not aware that dental health plays a major role as well. When tartar builds up on a dog’s teeth, it creates a lot of harmful bacteria. Once swallowed, the bacteria can get into the bloodstream, damaging the heart and other vital organs.
There are many ways to do a heart health checkup. The most simple is thorough an exam. When veterinarians listen to a dog’s heart, they can detect abnormal sounds that might indicate a problem.
Radiographs, or x-rays, are another common tool for detecting heart health. Veterinarians also use echocardiograms, blood pressure monitoring and blood tests.
Fun Facts About Chihuahua Hearts
- Do you know the thump-thump sound you hear when a Chihuahua’s heart beats? The valves opening and closing as blood moves in and out creates it.
- Being afraid or in pain will make their heart beat faster.
- A human heart and a Chihuahua’s heart are pretty much the same. Other than size, there’s only a few differences in the vessel and valves.
- A Chihuahua’s normal heart rate is as much as 65 beats-per-minute faster than larger breeds.
Final Thoughts: They May Be Small but They’re Mighty
A Chihuahua’s heart may be tiny, but it’s big on courage. It one of the AKCS’s top 50 most popular breeds for a reason. They’re incredibly cute, fiercely loyal and loving. Without a doubt, spending time with one of them will make your heart beat faster.