WHAT IS AN ELECTROCARDIOGRAM (ECG)
An electrocardiogram is a noninvasive medical procedure that is used to measure the electrical activity of the heart over a period of time using electrodes placed on the skin.
- Tiny electrical changes on the skin that arise from the heart during each heartbeat are detected by the electrodes.
- These electrodes are placed on the skin of the chest, arms and legs and information about the structure and function of the heart are learned.
- In some instances, men may need to have their chest shaved to allow for an optimal connection
- It is one of the safest and least invasive method used by millions of cardiologists in the world to detect problems in the heart.
- The electrocardiogram is shown in the form of electrical waves which are represented on graph paper.
- Electrocardiogram monitors or machines are used during the procedure
TYPES of ECG TEST
Resting 12-lead ECG- this is the standard test for measuring the heart’s electrical function. It is performed while the patient lies flat on his/her back while a computer creates a picture, on graph paper, of the electrical impulses moving through the heart. 12 electrodes are placed on the chest, arms, and legs at the same time.
Holter Monitor – the Holter monitor is a type of electrocardiogram used to monitor the electrical activity of the heart continuously for a period of 24 hours or longer. The electrodes are taped on the skin after which you may be asked to go home and continue with your daily routine except for the shower. The doctor may ask to keep tab of what you do and any symptoms noticed. It is mostly recommended if the doctor suspects palpitation or inadequate blood flow to your heart muscles.
Signal-Averaged electrocardiogram – it is a type of electrocardiogram that is more detailed. In this procedure, multiple electrical activities of the heart are obtained over a period of 20 minutes in order to capture abnormal heartbeats. This is to check if the patient is at a high risk of getting heart arrhythmia, which can cause cardiac arrest. The procedure is similar to the resting ECG but with highly sophisticated equipment.
WHAT IS MEASURED ON THE ECG?
- Rate and rhythm of heartbeats
- Size and positions of the heart chambers
- Presence of any damage to the heart’s muscle cells
- Presence of impaired blood flow to the heart
- Effects of cardiac drugs
- The function of implanted pacemakers
- Pattern of abnormal electric activity
WHEN IS AN ECG PERFORMED
- As a routine physical examination or evaluation
- As a cardiac exercise test
- As an evaluation of symptoms of chest pain, shortness of breath, fainting, palpitations, or dizziness.
WHAT CONDITIONS CAN BE DIAGNOSED?
- Abnormally fast or irregular heart rhythms
- Abnormally slow heart rhythms
- An enlarged heart
- Poor blood supply to the heart
- An abnormal position of the heart
- An inflammation of the heart
- Previous heart attack
- Damage to the heart
- Cardiac arrest during emergency room or intensive care monitoring
- Disturbances of the heart’s conducting system