Overview of an electrocardiogram
An electrocardiogram is a simple, painless test that measures the electrical activity of your heart. This is also known as an ECG or EKG. Each heartbeat is activated by an electrical signal that begins at the top of your heart and travels downward. Heart problems often affect the electrical activity of your heart.
Your doctor may recommend an EKG if you experience symptoms or signs that indicate a heart problem:
- Pain in your chest
- Difficulty breathing
- Feeling tired or weak
- Beating, running, or jumping with the heart
- The feeling that your heart is beating irregularly
- Detect abnormal sounds when your doctor listens to your heart
- The EKG helps your doctor determine the cause of your symptoms and what type of treatment is needed.
If you are 50 or older or have a family history of heart disease, your doctor may also order an EKG to look for early signs of heart disease.
Types of electrocardiogram
The EKG records a picture of your heart’s electrical activity as it is being monitored. However, some heart problems do arise. In these cases, you may need more or less specialized supervision.
Some heart problems only appear during exercise. During a stress test, you will have an EKG while you exercise. This test is usually done when you are on a treadmill or stationary bike.
Also known as an ambulatory ECG or ECG monitor, the Holter monitor records your heart activity for more than 24 to 48 hours, while you keep an activity diary to help your doctor determine the cause of your symptoms. The electrodes attached to your chest can be carried on a portable battery-operated monitor in your pocket, on your belt, or on your shoulder strap.
Symptoms that do not occur very frequently may require an event logger. It is similar to the Holter monitor but records the electrical activity of your heart when symptoms appear. Some event loggers are automatically triggered when features are detected. Other event loggers Press the button when you feel the functions. You can send the information directly to your doctor over the phone line.
What is this used for?
EKG tests are used to diagnose and/or monitor various heart disorders. In addition to:
- Irregular heartbeat (called arrhythmia)
- Blocked arteries
- The heart is damaged
- Heart failure
Heart attack: Electrocardiograms are often used in an ambulance, emergency room, or other hospital room to suspect a heart attack.
The ECG test is sometimes included in the routine test for middle-aged and older people because they have a higher risk of heart disease than younger people.
Why is an electrocardiogram test done?
An EKG is a painless, non-invasive way to help diagnose the most common heart problems in people of all ages. Your doctor may use an EKG to diagnose or diagnose:
- Abnormal heart rhythm (arrhythmia)
- If the arteries in your heart are blocked or narrow (coronary artery disease) causing chest pain or heart attack
- Have you had a previous heart attack?
- How well some heart disease treatments like pacemakers work
You may need an ECG if you have the following signs and symptoms:
- Chest pain
- Dizziness, mild headache, or confusion.
- Heart palpitations
- Rapid pulse
- Difficulty breathing
- Weakness, fatigue, or decreased ability to exercise.
The American Heart Association does not recommend the use of electrocardiograms to assess low risk in asymptomatic adults. If you have a family history of heart disease, even if you don’t have symptoms, your doctor may prescribe an EKG as a screening test.
If your symptoms come and go, they won’t be captured during a standard ECG recording. In this case, your doctor may recommend remote or continuous ECG monitoring. There are many types.
Holter monitor: The Holter monitor is a small, portable device that records a continuous ECG, usually for 24 to 48 hours.
Event monitor: This portable device is similar to the Holter monitor, but it only records a few minutes at a time. It may take longer than a Holter monitor, typically 30 days. When you normally experience symptoms, you press a button. Some devices will automatically record when an abnormal rhythm is detected.
What are the limitations of the electrocardiogram?
The EKG is a stable image and may not reflect serious heart problems when the patient is symptom-free. A very common example is that of a patient with a history of intermittent chest pain due to severe underlying coronary artery disease. This patient may have a completely normal ECG when not experiencing any symptoms. In such cases, the ECG recorded on the stress test may reflect the underlying abnormality, while the ECG taken at rest may be normal.
Most abnormal patterns on the EKG are unspecified, meaning they can be seen with a variety of conditions. They can be a simple variant and do not reflect any anomaly. The doctor can often standardize these conditions with a detailed examination and sometimes with other cardiac tests (eg, echocardiogram, stress test).
In some cases, the EKG can be completely normal despite the heart condition that is usually reflected on the EKG. The reasons for this are largely unknown, but it is important to remember that a simple EKG does not necessarily exclude the possibility of heart disease. Also, a patient with cardiac symptoms often needs additional evaluations and tests.
What does the ECG (EKG) measure? What heart problems does it diagnose?
- The underlying heart rate and rhythm mechanism.
- The inclination of the heart in the chest cavity (how it is positioned)
- Evidence of increased thickness (hypertrophy) of the heart muscle.
- Evidence of damage to various parts of the heart muscle.
- Evidence that blood flow to the heart muscle is severely affected.
- Abnormal electrical activity patterns leading to abnormal heart rhythm disturbances in the patient
- Electrocardiograms can confirm:
- Abnormally fast or irregular heart rhythms
- Abnormally slow heart rhythms
- Abnormal circulation of cardiac impulses, which may indicate underlying cardiac or metabolic disorders.
- Evidence of a pre-existing heart attack (myocardial infarction)
- Evidence of a severe heart attack in progress
- Evidence of severe impairment of blood flow to the heart during a threatening episode of heart attack (transient angina)
- Adverse effects on the heart of various heart diseases or systemic diseases (hypertension, thyroid conditions, etc.)
- Adverse effects on the heart of certain lung and lung conditions (emphysema, pulmonary embolism [blood clots in lungs and lungs]))
- Some congenital heart defects
- Evidence of abnormal blood electrolytes (potassium, calcium, magnesium)
- Evidence of inflammation of the heart or its lining (myocarditis, pericarditis)
How should I prepare?
Here are some things you can do to prepare:
Avoid oily or oily skin creams and lotions on the day of the test, as they can keep the electrodes in contact with your skin.
Avoid long knitwear, as the electrodes must be kept straight across your legs.
Wear a shirt that can be easily removed to keep the cables on your chest.
What can I expect during the electrocardiogram test?
The ECG is a non-invasive procedure which means that nothing is injected into the body.
- It is painless.
- Many electrodes, usually 12 to 15 in all, are placed on various parts of your body, including your arms, legs, and chest.
- The electrodes are attached using small suction cups or adhesive patches.
- Sensors in the pads detect the electrical activity of your heart.
- The test is usually done when you are at rest.
- The results are usually recorded on graph paper and are understood or read by your doctor or technician.
- The test usually lasts 5 to 10 minutes.
If you need more detailed information, check with the center where the test is performed.
It will lie flat during the test as you create a computer image on graph paper of the electrical impulses moving through your heart. This is called a “relaxation” EKG, but you can use the same test to monitor your heart while you exercise.
Your doctor will archive your EKG samples so you can compare them with future tests.
After Electrocardiogram test
You can resume your normal activities after your EKG.
Your doctor can discuss your results with you on the day of your EKG or at your next appointment.
If your Electrocardiogram result is normal, you don’t need any other tests. If the results show abnormalities in your heart, you may need another ECG or other diagnostic tests such as an echocardiogram. Treatment depends on the cause of your signs and symptoms.
Your doctor will review the information recorded by the ECG machine and if there is a problem with your heart,
- Heart rate. Generally, your heart rate can be measured by monitoring your pulse. An Electrocardiogram can help to accurately calculate if your pulse is hard to feel or if it is too fast or too irregular. An ECG can help your doctor detect an abnormally fast heart rate (tachycardia) or an abnormally slow heart rate (bradycardia).
- Heart rate. An ECG shows cardiac arrhythmias. These conditions can occur when some part of the heart’s electrical system is not working. In other cases, medications such as beta-blockers, cocaine, amphetamines, and over-the-counter cold and allergy medications can trigger arrhythmia.
- Heart attack. An ECG can show evidence of a previous heart attack or progression. The samples on the ECG indicate which part of your heart is damaged, as well as the extent of the damage.
- Inadequate supply of blood and oxygen to the heart. An ECG done when you have symptoms can help your doctor determine if chest pain is caused by decreased blood flow to the heart muscle, such as transient angina chest pain.
- Structural abnormalities. An Electrocardiogram can provide clues about the expansion of the heart’s chambers or walls, heart defects, and other heart problems.
If your doctor finds any problems with your ECG, she may order additional tests to see if treatment is needed.