ECG- ELECTROCARDIOGRAM

• ELECTROCARDIOGRAM(ECG)

GENERAL INTRODUCTION 🤔

👉 An electrocardiogram records the electrical signals in your heart. It's a common and painless test used to quickly detect heart problems and monitor your heart's health.

👉 Electrocardiograms — also called ECGs or EKGs — are often done in a doctor's office, a clinic or a hospital room. ECG machines are standard equipment in operating rooms and ambulances. Some personal devices, such as smart watches, offer ECG monitoring. Ask your doctor if this is an option for you.

👉 Electrocardiography is the process of producing an electrocardiogram (ECG or EKG) . It is a graph of voltage versus time of the electrical activity of the heart using electrodes placed on the skin. These electrodes detect the small electrical changes that are a consequence of cardiac muscle depolarization followed by repolarization during each cardiac cycle (heartbeat).

👉 Changes in the normal ECG pattern occur in numerous cardiac abnormalities, including cardiac rhythm disturbances (such as atrial fibrillation and ventricular tachycardia), inadequate coronary artery blood flow (such as myocardial ischemia and myocardial infarction), and electrolyte disturbances (such as hypokalemia and hyperkalemia).

Types📝:-
👉 Holter monitor
👉 Implantable loop recorder

Why it's done🤔🤔🤔?

👉 An electrocardiogram is a painless, noninvasive way to help diagnose many common heart problems in people of all ages. Your doctor may use an electrocardiogram to determine or detect:

👉 Abnormal heart rhythm (arrhythmias).

👉 If blocked or narrowed arteries in your heart (coronary artery disease) are causing chest pain or a heart attack.

👉 Whether you have had a previous heart attack.

👉 How well certain heart disease treatments, such as a pacemaker, are working.

👉 You may need an ECG if you have any of the following signs and symptoms:

👉 Chest pain
👉 Dizziness, lightheadedness 
👉 confusion
👉 Heart palpitations
👉 Rapid pulse
👉 Shortness of breath
👉  Weakness, fatigue or a decline in ability to exercise

👉 The American Heart Association doesn't recommend using electrocardiograms to assess adults at low risk who don't have symptoms. But if you have a family history of heart disease, your doctor may suggest an electrocardiogram as a screening test, even if you have no symptoms.

👉 If your symptoms tend to come and go, they may not be captured during a standard ECG recording. In this case your doctor may recommend remote or continuous ECG monitoring. There are several different types.

Holter monitor📝:-
👉 A Holter monitor is a small, wearable device that records a continuous ECG, usually for 24 to 48 hours.

Event monitor📝:-
👉 This portable device is similar to a Holter monitor, but it records only at certain times for a few minutes at a time. You can wear it longer than a Holter monitor, typically 30 days. You generally push a button when you feel symptoms. Some devices automatically record when an abnormal rhythm is detected.

Electrocardiograph machines📝:-

👉 Electrocardiographs are recorded by machines that consist of a set of electrodes connected to a central unit. Early ECG machines were constructed with analog electronics where the signal drove a motor to print out the signal onto paper. Today, electrocardiographs use analog-to-digital converters to convert the electrical activity of the heart to a digital signal. Many ECG machines are now portable and commonly include a screen, keyboard, and printer on a small wheeled cart. Recent advancements in electrocardiography include developing even smaller devices for inclusion in fitness trackers and smart watches. These smaller devices often rely on only two electrodes to deliver a single lead I. Portable six-lead devices are also available.

👉 Recording an ECG is a safe and painless procedure.The machines are powered by mains power but they are designed with several safety features including an earthed (ground) lead. Other features include:

👉 Defibrillation protection: any ECG used in healthcare may be attached to a person who requires defibrillation and the ECG needs to protect itself from this source of energy.

👉 Electrostatic discharge is similar to defibrillation discharge and requires voltage protection up to 18,000 volts.
Additionally circuitry called the right leg driver can be used to reduce common-mode interference (typically the 50 or 60 Hz mains power). ECG voltages measured across the body are very small. This low voltage necessitates a low noise circuit and instrumentation amplifiers. Simultaneous lead recordings: Earlier designs recorded each lead sequentially, but current models record multiple leads simultaneously. Most modern ECG machines include automated interpretation algorithms. This analysis calculates features such as the PR interval, QT interval, corrected QT (QTc) interval, PR axis, QRS axis, rhythm and more. The results from these automated algorithms are considered "preliminary" until verified and/or modified by expert interpretation. Despite recent advances, computer misinterpretation remains a significant problem and can result in clinical mismanagement.

Risks📝:-
👉 An electrocardiogram is a safe procedure. There is no risk of electrical shock during the test because the electrodes used do not produce electricity. The electrodes only record the electrical activity of your heart.

👉 You may have minor discomfort, similar to removing a bandage, when the electrodes are removed. Some people develop a slight rash where the patches were placed.

How you prepare📝

👉 No special preparations are necessary for a standard electrocardiogram. Tell your doctor about any medications and supplements you take. These can often affect the results of your test.

What you can expect📝📝📝
👉 An electrocardiogram can be done in a doctor's office or hospital and is often done by a nurse or technician.

Before📝
👉 You may be asked to change into a hospital gown. If you have hair on the parts of your body where the electrodes will be placed, the technician may shave the hair so that the patches stick.

👉 Once you're ready, you'll be asked to lie on an examining table or bed.

During📝:-

👉 During an ECG, up to 12 sensors (electrodes) will be attached to your chest and limbs. The electrodes are sticky patches with wires that connect to a monitor. They record the electrical signals that make your heart beat. A computer records the information and displays it as waves on a monitor or on paper.

👉 You can breathe normally during the test, but you will need to lie still. Make sure you're warm and ready to lie still. Moving, talking or shivering may distort the test results. A standard ECG takes a few minutes.

After📝:-
👉 You can resume your normal activities after your electrocardiogram.

Results📝:-

👉 Your doctor may discuss your results with you the same day as your electrocardiogram or at your next appointment.

👉 If your electrocardiogram is normal, you may not need any other tests. If the results show an abnormality with your heart, you may need another ECG or other diagnostic tests, such as an echocardiogram. Treatment depends on what's causing your signs and symptoms.

👉 Your doctor will review the information recorded by the ECG machine and look for any problems with your heart, including:

Heart rate📝

👉  Normally, heart rate can be measured by checking your pulse. An ECG may be helpful if your pulse is difficult to feel or too fast or too irregular to count accurately. An ECG can help your doctor identify an unusually fast heart rate (tachycardia) or an unusually slow heart rate (bradycardia).

Heart rhythm📝

👉 An ECG can show heart rhythm irregularities (arrhythmias). These conditions may occur when any part of the heart's electrical system malfunctions. In other cases, medications, such as beta blockers, cocaine, amphetamines, and over-the-counter cold and allergy drugs, can trigger arrhythmias.

Heart attack📝

👉  An ECG can show evidence of a previous heart attack or one that's in progress. The patterns on the ECG may indicate which part of your heart has been damaged, as well as the extent of the damage. Inadequate blood and oxygen supply to the heart. An ECG done while you're having symptoms can help your doctor determine whether chest pain is caused by reduced blood flow to the heart muscle, such as with the chest pain of unstable angina.

Structural abnormalities📝

👉 An ECG can provide clues about enlargement of the chambers or walls of the heart, heart defects and other heart problems.