In this post, our Norristown vets discuss ECGs for dogs and cats, when your vet will order one and how to understand your pet's results.
What is an ECG?
An ECG, also known as an EKG, stands for electrocardiogram. It is a non-invasive test for monitoring your pet's heart. Small sensors attached to the skin monitor electrical activity to provide an image of the heart's activity.
What does an ECG tell your veterinarian about your pet?
An ECG tells your vet several things about your pet's heart. For one, it reads the rate and rhythm of the heartbeat. It also gives them an understanding of the electrical impulses that are going through each section of the heart.
A typical ECG consists of a pattern: a small bump that rises up, called the P-wave, then a large spike upward, called the QRS complex, and then another small bump called the T-wave.
The P-wave represents the atria contracting. The QRS complex occurs when the ventricles depolarize, or when the heart contracts in the typical 'heartbeat' rhythm. The T-wave represents the heart repolarizing (repolarizing just means the heart is undergoing a phase of relaxation and resetting its electrical state).
Your veterinarian will examine the wave's shape and measure the distance between its various parts. The P-Wave and QRS complex interval information is frequently of concern. These indicate the rate at which the heart takes in and pumps blood.
This is important to know because it directly affects a pet’s overall health and well-being. A healthy heart ensures that oxygen and nutrients are delivered to all parts of the body, allowing your pet to maintain proper organ function and energy levels. Additionally, a normal heart rate helps remove waste products from tissues, supports a strong immune system, and promotes optimal cardiovascular fitness.
The next major source of information is the peaks of the QRS complex and the distance between them. If there is a constant distance between the spikes you have a regular heartbeat. If they vary, you have an irregular heartbeat.
What are normal cat and dog ECGs?
The normal rhythm for a canine ECG should be 60 to 170 beats per minute. The normal rhythm of a cat’s ECG should be 140 to 220 beats per minute.
Are ECGs safe?
Yes, ECG tests are safe. ECG is a non-invasive diagnostic test that passively monitors the heart.
When would a vet use an ECG?
Your vet may order an ECG for your cat in any of these circumstances:
Abnormal Cardiovascular Rhythm
Cardiac murmurs, gallop sounds, and arrhythmias are a few examples of obvious abnormalities that may necessitate an ECG. These are common symptoms of diastolic dysfunction in dogs and cats, and an ECG is always recommended in these cases.
Arrhythmias can be caused by intracardiac or extracardiac disease, and an ECG can aid in the diagnosis of primary cardiomyopathy and/or infiltrative cardiac disease. The ECG also helps determine the best anti-arrhythmic therapy for each patient.
Heart disease is heritable in many dog and cat breeds. Dog breeds that commonly suffer from this disease include the Doberman Pinscher, Great Dane, Boxer, and Cocker Spaniel, while American Shorthair, Persian, and Maine Coon cats are more likely than other feline breeds to be diagnosed.
Thoracic Radiographic Changes
X-rays may be able to show enlargement of the heart or fat tissue around the heart. But an ECG is the most accurate method for measuring the dimensions of each cardiac chamber, and it is also useful for determining the cause of an enlarged heart detected in X-rays.
Cats can be particularly challenging cardiac patients because they may have severe cardiomyopathy or other heart conditions despite showing no outward symptoms. For cats, an ECG is frequently the only specific diagnostic procedure available that is sensitive enough to detect heart problems.
As heart disease is more common in purebred cats, an ECG evaluation is frequently advised to confirm the presence of heart disease and identify the patient's therapeutic requirements.
How much is an ECG for a dog or cat?
It's always best to contact your vet directly if you're curious about the cost. They should be able to provide you with an accurate estimate.
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.