ECG for Pets: When it's Needed?

In this blog post, our vets in Novato will talk about ECGs (electrocardiograms) for dogs and cats. You will learn when your vet may need to order an ECG for your pet and how to interpret the results. Understanding your pet's ECG results will help you make informed decisions about their healthcare.

What is an ECG?

An ECG, also known as an EKG, is a test that monitors the heart by tracking its electrical activity through sensors attached to the skin. It is a safe and painless method of observing the heart in animals and humans without any invasive procedures.

What Does an ECG Tell Your Veterinarian About Your Dog or Cat?

An ECG test provides important information about your pet's heart to your vet. It tells them how fast and regularly your pet's heart beats and how electrical signals are moving through each part of the heart. The ECG shows a wave pattern that represents different actions of the heart. For instance, the P wave indicates when the atria contract, the QRS complex shows when the ventricles contract and the T wave shows when the ventricles relax. 

To diagnose potential issues, the vet looks for specific data, such as the shape and distance between the waves. They pay special attention to the PR interval and QRS complex interval, which indicates how quickly the heart is taking in and pumping out blood. The distance between the peaks of the QRS complex is also important. If the distance is the same, the heartbeat is regular, but if it varies, it is irregular.

The vet can determine the heart rate by counting the number of QRS complexes over a certain time interval. However, it's important to note that the rate and rhythm of your pet's heartbeat may vary depending on their breed. So, it's always better to consult your veterinarian to learn more about what values are expected of your pet.

Are ECG Safe

ECG tests are safe because they are non-invasive and passively monitor the heart as a diagnostic test.

When Would a Vet Use an ECG

Some examples of when a vet may order an ECG test are:

Abnormal Cardiovascular Physical Exam

During a physical examination, a veterinarian may notice certain abnormalities in an animal's heart, such as cardiac murmurs, gallop sounds, or arrhythmias. These abnormalities could indicate a problem with the heart's ability to relax, which is referred to as diastolic dysfunction. An echocardiogram is typically recommended for dogs and cats to diagnose such conditions. Arrhythmias, which are irregular heartbeats, can be caused by heart disease or other underlying conditions. An echocardiogram can help identify underlying problems such as primary cardiomyopathy or infiltrative cardiac disease. Additionally, it can assist the veterinarian in determining the best anti-arrhythmic therapy for the animal.

Breed Screening

Certain breeds of dogs and cats are more likely to inherit heart disease. Sometimes, a cardiologist must listen to their hearts with a stethoscope to check for unusual sounds. If there is a murmur, a complete evaluation using an echo is needed. However, an echo is always needed for some breeds to check for heart disease.

Thoracic Radiographic Changes

Cardiomegaly means that the heart looks bigger than normal in X-rays. This can be because the heart is actually more significant, there is extra fat around it, or because of differences between people. To find out why the heart looks big, doctors often use a test called an echocardiogram. This test is very good at measuring the size of the heart's different parts and can help determine if the big heart is causing problems like heart failure or high blood pressure in the lungs.

Feline Echocardiography

Cats can suffer from heart problems even if they appear healthy during a physical examination or on an X-ray. Therefore, an echocardiogram is the most accurate detection of cat heart disease. Purebred cats are more susceptible to heart disease, so it is crucial to perform this test. In addition, an echocardiogram can assist in determining the best course of treatment if a cat is diagnosed with heart disease.

Pre-Anesthetic Evaluation

Knowing their heart health is applicable before giving a dog or cat anesthesia.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Our veterinarians in Novato can help if you're concerned about your pet's heart. Call us to book a consultation.