What is an ECG?
An ECG is an acronym for electrocardiogram. It is a test used to monitor your pet's heart. Little sensors attached to the skin monitor electrical activity to give a representation of what the heart is doing.
This is a non-invasive way of observing the heart in pets.
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 gives 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 is when the ventricles depolarize, or the large contraction of the heart that is the typical 'heartbeat'. The T-wave represents the heart repolarizing.
Your veterinarian will check the shape of the wave and measure the distance between its various parts. Frequently, the P-wave and QRS complex intervals provide information that is of concern. These indicate how fast the heart takes in blood and pumps it.
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 cats 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?
Some examples of when a vet may order an ECG are:
Abnormal Cardiovascular Rhythm
Cardiac murmurs, gallop sounds, and arrhythmias are some obvious abnormalities that may necessitate an ECF. These can often be an indication of diastolic dysfunction and an ECG is always warranted when this occurs in dogs and cats.
ECGs can be caused by either intracardiac or extracardiac disease, and they help rule out primary cardiomyopathy and/or infiltrative cardiac disease. The ECG can also help determine the best anti-arrhythmic therapy for each individual patient.
Breed Screening
Many dog and cat breeds are genetically predisposed to heart disease. Dog breeds include the Doberman Pinscher, Great Dane, Boxer, and Cocker Spaniel, to name a few. Cat breeds include the Maine Coon, Persian, Ragdoll, and some American Shorthairs.
Thoracic Radiographic Changes
Cardiomegaly on radiographs can be caused by cardiac enlargement, pericardial fat accumulation, or patient variability. An ECG is the most precise tool for measuring the size of each cardiac chamber and is extremely useful in determining the cause of radiographic cardiomegaly.
Feline Echocardiography
Cats can be particularly difficult cardiology patients because they can have severe cardiomyopathy or other heart diseases despite showing no clinical symptoms. An ECG is frequently the only diagnostic test that is both specific and sensitive in cats.
Purebred cats have a higher incidence of heart disease, therefore an ECG evaluation is often recommended to confirm the presence of heart disease and determine the therapeutic needs of the patient.
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 only. Taylor Veterinary Emergency does not offer ECGs at this time.