
An electrocardiogram, commonly known as an EKG or ECG, is a non-invasive medical test that records the electrical activity of your heart.1 An EKG or ECG is a simple yet powerful tool that can help your doctor detect a wide range of cardiac abnormalities, from irregular heart rhythms to evidence of a heart attack.2
Each time your heart beats, an electrical impulse travels through its chambers, causing the muscle to contract and pump blood throughout your body. An EKG captures these electrical signals and displays them as a series of waves on a moving strip of paper or a digital screen. By analyzing the pattern, size, and duration of these waves, a doctor can gain crucial insights into the heart's function and identify potential issues.1
An EKG or ECG is characterized by a series of distinct waves, each corresponding to a specific electrical event in the heart.
By analyzing the timing, shape, and sequence of these waves and segments, doctors can assess your heart rate, rhythm, and overall cardiovascular health.
While often used interchangeably, heart rate, pulse, and rhythm refer to distinct aspects of your heart's function, all of which are measured by an EKG:
An EKG provides a visual representation of both the rate and the rhythm of the heart, allowing a physician to make a thorough assessment of its electrical health.
An EKG is a powerful tool that helps medical professionals detect a variety of heart conditions by analyzing the heartâs electrical activity. Some of the most common conditions an EKG can help diagnose include:
By highlighting these patterns, an EKG provides critical insights that guide diagnosis, monitoring, and treatment, making it one of the first steps in evaluating heart health.
Your doctor may recommend an EKG for various reasons, including the investigation of symptoms that could indicate a heart problem. These symptoms often include2:
EKGs are also used to monitor the health of individuals with known heart conditions, to assess the effectiveness of treatments like pacemakers or medications, and as part of a routine check-up to screen for potential heart disease, especially in individuals with risk factors such as high blood pressure, high cholesterol, smoking, diabetes, or a family history of heart disease.5
An EKG or ECG can be performed in several different ways depending on what your doctor needs to learn about your heart. Some tests are done while youâre resting, others capture how your heart responds to exercise, and some monitor your rhythm continuously over hours or days. Understanding the main types of EKGs can help you know what to expect and why your doctor may recommend one test over another.
The most comprehensive type of electrocardiogram is the 12-lead EKG, typically performed in a hospital or clinic setting. This test uses 10 to 12 small, sticky electrodes placed on the chest, arms, and legs. These electrodes capture the heart's electrical activity from 12 different angles, providing a detailed, three-dimensional view of the heart. This level of detail is essential for accurately diagnosing complex heart conditions.1,2
A stress or exercise EKG records your heartâs electrical activity while your heart rate and blood pressure increase through controlled physical activityâlike walking on a treadmill or pedaling a stationary bike. Throughout the test, clinicians monitor your ECG tracings, symptoms, blood pressure, and how quickly your heart recovers afterward. The goal is to see how your heart performs when itâs working harder than it does at rest.
Because many arrhythmias are brief or unpredictable, doctors often prescribe extended monitoring tools (also called ambulatory monitoring devices) that record the heartâs rhythm over longer periods. This may include a Holter monitor, event recorder, or implantable loop recorder.
A convenient, over-the-counter, and often more affordable option, is a personal EKG. These portable, handheld devices make it possible to record an EKG from anywhere and at any timeâlike when youâre experiencing one of the symptoms mentioned earlier. Personal EKGs typically record fewer leads than an in-hospital EKG (usually a 1- or 6-lead), but are still highly effective at detecting rhythm abnormalities. Personal EKGs offer a convenient way to monitor your heart proactively and share important data with your doctor remotely.
An EKG is more than just a test, itâs a window into how your heart is working in real time. With options ranging from clinical to at-home monitoring, you have more ways than ever to stay informed and involved in your heart health. If youâre exploring tools that can support you between appointments, ask your doctor whether a personal EKG like Kardia could be a helpful part of your care plan.
Kardia personal EKGs do not check for heart attack and do not replace regular health checkups with your physician. Seek medical attention if you are experiencing any concerning symptoms or if you are having an emergency.
1. https://www.ncbi.nlm.nih.gov/books/NBK536878/
2. https://www.mayoclinic.org/tests-procedures/ekg/about/pac-20384983
3. https://www.ncbi.nlm.nih.gov/books/NBK549803/
4. https://my.clevelandclinic.org/health/diagnostics/16953-electrocardiogram-ekg
5. https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/electrocardiogram
6. https://my.clevelandclinic.org/health/diagnostics/heart-rate
7. https://www.mayoclinic.org/diseases-conditions/heart-arrhythmia/symptoms-causes/syc-20350668