Home Tests and Procedures Deep Dive Into ECGs and How They Help Medical Professionals

Deep Dive Into ECGs and How They Help Medical Professionals

Verified By Apollo Cardiologist October 7, 2020 9708 0

Electrocardiogram (ECG or EKG) is used by doctors to check a person’s heart rate and rhythm. This test helps doctors detect a heart attack, heart disease, any abnormal heart rhythms, or an enlarged heart that may result in heart failure.

It records the heart’s electrical activity through tiny electrode patches attached to the skin of the person’s arms, legs, and chest. ECG is a safe, quick, and painless testing technique that helps doctors to-

  • Check your heart rhythm
  • Detect a heart attack.
  • Diagnose poor blood flow to the heart muscles, also known as ischemia.
  • Detect other cardiac abnormalities, such as thickened heart muscles.
  • Detect major abnormalities in the electrolyte levels, such as low or high calcium, high potassium, etc.

An ECG machine is a piece of standard equipment in every operating room and ambulances. Some smart gadgets also have an ECG testing facility.

Types of ECG testing

If you have any symptoms related to heart problems, your doctor may recommend conducting an ECG test. The different types of ECG tests that can be conducted include –

  • Standard ECG

In a standard ECG testing, small electrode patches are attached to the skin of the chest, legs, and arms of the person, which captures the reading of the heart’s electrical activity. This is a painless and non-invasive testing technique used to detect the heart rhythm at any point in time.

  • Holter Monitor

This is a small, wearable device that provides a continuous reading of the ECG recording. The device is used to capture the reading for 24 to 48 hours. This test is conducted after performing the conventional ECG  test for checking the heart rhythm.

  • Implantable loop recorder

This is a type of heart monitoring device that provides recordings of your heart rhythms continuously for up to three years. It enables the recording of your heart’s electrical signals through remote monitoring with a tiny device inserted just beneath the chest’s skin.

  • Event monitor

This portable device is similar to the Holter monitor, which records the heart rhythm only at certain times for a few minutes. This can be worn for longer than a Holter monitor. Each time you observe any symptoms related to cardiac problems, a single push of a button will record and store the heart’s electrical activity for a few minutes, which the physician can later study.

  • Signal-averaged electrocardiogram

This test detects any possible risk of getting a condition known as heart arrhythmia, resulting in cardiac arrest. While the test is similar to a standard ECG, it makes use of more advanced technology for analyzing such risks.

What are the symptoms indicating the need for ECG?

Your doctor may recommend an ECG  if you experience any of the following symptoms –

  • Heart palpitation
  • Breathlessness or difficulty in breathing
  • Chest pain
  • Confusion or lightheadedness, and dizziness
  • High pulse rate
  • Fatigue, weakness, and decline in the ability to exercise

However, if you have a family history of cardiac disease, your doctor might recommend an electrocardiogram as a screening test, even if you do not show any symptoms of heart problems.

 What to expect from ECG testing?

 ECG testing is usually done under professional medical supervision in a clinic or hospital. Here is what you will experience before, during, and after an echocardiogram

· Before an ECG

You will need to change into a hospital gown. If your body’s area where the electrodes need to be placed has hair, the technician will shave the hair so that the electrodes stick to the body. Once you are ready, you will be asked to lie on a bed or examining table.

· During an ECG

During the examination, up to 12 sensors can be attached to your limbs and chest. The electrodes contain adhesive pads with wires connected to a monitor, recording the electrical signals as your heartbeats. A computer captures the reading and displays it on the monitor screen or paper.

While you are allowed to breathe normally during the test, you need to lie still for a few minutes while the testing is being done. Moving or talking during the test might produce distorted results.

· After an ECG

There are no restrictions imposed after the testing is complete. You can resume your normal activities after the ECG test has been done.

Call 1860-500-1066 to book an appointment.

Risk factors associated with ECG

An ECG is a completely safe procedure with no risk of getting an electrical shock during the testing. During the testing process, the electrodes do not produce any electricity and record only the electrical activity of your heart.

 Reviewing the ECG test results

Your doctor will review the ECG recordings, usually on the same day as the test, to identify any complications with your heart, including:

  • Heart rhythm: An ECG test helps detect irregularities in the heart rhythm, which occurs when a part of the heart’s electrical system malfunctions. Sometimes, certain medications like amphetamines, beta-blockers, OTC cold and allergy drugs, and beta-blockers may trigger abnormal rhythms .
  • Heart rate: An ECG test provides accurate results for people with an irregular pulse count or if the pulse is difficult to check. It helps doctors in identifying an unusually fast or slow heartbeat.
  • Heart attack: The ECG report patterns help to indicate which part of the heart is damaged or the extent of the damage caused. It shows evidence of a previous heart attack or one that is in progress.
  • Structural abnormalities: An ECG test can provide valuable insights about the enlargement of chambers or walls of the heart, and any other heart problems or defects.
  • Inadequate oxygen and blood supply to the heart: AN ECG test performed while you are showing cardiac  symptoms will help your doctor determine the underlying cause of such problems and whether it is due to reduced blood and oxygen supply to the heart.


The ECG makes use of standard terminology across different hospitals and countries for diagnosing test reports. The doctor will determine the type of ECG testing that will be appropriate in your case after checking your present health condition. If there is any abnormality in the ECG test report, your doctor may prescribe other additional tests to decide the future course of action.

Frequently Asked Questions (FAQs):

1. What is a normal ECG reading?

Each ECG cycle has 5 waves: P, Q, R, S, T corresponding to different phases our the heart activities. While the P wave represents normal atrium (upper heart chambers) depolarization, the QRS complex (one single heart beat) corresponds to depolarization of the left and right ventricles (lower heart chambers) and the T wave represents  re-polarization (or recovery) of the ventricles. To interpret ECG, you needs to focus on the heart rate (frequency), shape, size and regularity of each individual waves and the timing as well as interaction between waves.

2. How accurate is the ECG  for diagnosing a heart attack?

An ECG is an important test in suspected heart attacks. Heart attacks can be classified by measuring an ECG called the ST segment. This corresponds to the damage area inflicted on the heart.

3. Can ECG help to detect blocked arteries?

Your doctor might use electrocardiogram testing for determining or detecting abnormal heart rhythm  caused by poor blood supply to the heart due to coronary arteries being blocked. The ECG can also determine whether you have had a heart attack before.

Call 1860-500-1066 to book an appointment.

Verified By Apollo Cardiologist

The content is reviewed and verified by our experienced and highly specialized team of heart specialists who diagnose and treat more than 200 simple-to-complex heart conditions. These specialists dedicate a portion of their clinical time to deliver trustworthy and medically accurate content

8000+ Top doctors Associated and Apollo Hospitals is continuosly ranked as No1 Multispecialty Hospitals in India with best in class treatments for Cancer, Knee replacements, Liver Transplant, Heart, Diabetes, Kidney.

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