In this post, our Torrance vets will discuss ECGs for dogs and cats when your vet will order one as well as how to understand your pet's results so you can make the best decisions regarding their health care.
What is an ECG?
Did you know that an electrocardiogram (ECG), also known as an EKG, is used to monitor the heart's activity? This test involves attaching small sensors to the skin that monitor electrical activity and provide a representation of the heart's function. The best part is that this test is non-invasive, making it a safe and reliable way to observe the heart in pets and humans.
What Does an ECG Tell Your Veterinarian About Your Pet?
Your pet's heart can be analyzed through an ECG, which provides information about the rate, rhythm, and electrical impulses flowing through different sections of the heart. A typical ECG shows a pattern of a small bump called the P wave, a large upward spike known as the QRS complex, and another small bump called the T wave. The P wave signifies the atria contracting, while the QRS complex represents the ventricles depolarizing. The T wave shows the ventricles' repolarization.
Your veterinarian will look for correct wave shapes and distances between different parts of the wave, paying particular attention to the PR interval and the QRS complex interval. These intervals indicate the heart's speed in taking in and pumping out blood. Measuring the distance between the peaks of the QRS complex also helps determine if the heartbeat is regular or irregular. Additionally, counting the QRS complexes over a specific time interval can provide the heart rate.
It's important to note that cats and dogs may have different heart rates and rhythms, so it's best to consult your veterinarian about the expected values for your pet's breed.
Are ECG Safe
ECG tests are completely safe. This diagnostic test is non-invasive and monitors the heart without causing any harm.
When Would a Vet Use an ECG
Here are some instances where a veterinarian may request an ECG examination:
Abnormal Cardiovascular Physical Exam
During a physical exam, cardiac murmurs, gallop sounds, and arrhythmias may indicate the need for an echocardiogram in both dogs and cats. Diastolic dysfunction is a common cause of these abnormalities, and it is important to rule out primary cardiomyopathy and infiltrative cardiac disease that could be contributing factors. Arrhythmias can be caused by either intracardiac or extracardiac disease. An echocardiogram helps identify any underlying issues and determine the most effective anti-arrhythmic therapy for each patient.
Breed Screening
Some breeds of dogs and cats may have a genetic tendency towards heart disease. To confirm the absence of a murmur, a board-certified cardiologist may need to listen to the heart. If a murmur is detected, an echo may be recommended for a thorough evaluation. However, an echo may be routinely advised in certain breeds to detect any potential heart issues.
Thoracic Radiographic Changes
Cardiomegaly noted on radiographs can be due to cardiac enlargement, pericardial fat accumulation, and/or patient variability. An echocardiogram is the most specific tool for determining the size of each cardiac chamber and is a very useful tool in delineating a cause for radiographic cardiomegaly. The echocardiogram is highly specific and sensitive for congestive heart failure and pulmonary hypertension.
Feline Echocardiography
Cardiology cases involving cats can pose a particular challenge since they can develop severe cardiomyopathy, even without any physical exam abnormalities, clinical signs, or radiographic changes. An echocardiogram is the most appropriate diagnostic procedure to accurately diagnose heart disease in cats, as it is both specific and sensitive. Purebred cats are more susceptible to heart disease, and thus, echocardiographic evaluation is highly recommended for these patients. In cases where heart disease is suspected, an echocardiogram is necessary to confirm its presence and determine the necessary treatment for the patient.
Pre-Anesthetic Evaluation
Before placing a dog or cat under anesthesia, obtaining a complete understanding of the patient's cardiovascular status can be helpful.
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.