In this post, our Upland 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, is an acronym that stands for electrocardiogram. It’s a test used to monitor your dog or cat’s heart. Little sensors attach to the skin and 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 that the wave is the right shape and measure the space between the wave's various components. The information provided by the P-Wave and the QRS complex interval are frequently the causes for concern. These indicate how quickly the heart is pumping blood and how quickly it is absorbing blood.
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 extracardiac or intracardiac diseases, and an ECG can help rule out primary cardiomyopathy and/or infiltrative cardiac disease. Determining the best antiarrhythmic therapy for each patient is assisted by the ECG.
Heart disease is heritable in many breeds of dogs and cats. Dog breeds include the Doberman Pinscher, Great Dane, Boxer, and Cocker Spaniel, to name a few. Breeds of cats include the Maine Coon, Persian, Ragdoll, and some American Shorthairs.
Thoracic Radiographic Changes
On radiographs, cardiomegaly can be caused by cardiac enlargement, pericardial fat accumulation, and/or patient variability. An ECG is the most accurate tool for determining the size of each cardiac chamber and is crucial in determining the cause of radiographic cardiomegaly.
Cats can be particularly difficult cardiology patients because they can have severe cardiomyopathy or other heart diseases despite showing no clinical signs. An ECG is frequently the only diagnostic test that is both specific and sensitive for 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: This post is for informational purposes only. Inland Valley Veterinary Specialists is unable to offer ECGs at this time.