Reasons & Procedure For Conducting an Electrocardiogram (ECG) Test

Submitted on March 27, 2012

What is an Electrocardiogram (ECG)?

An electrocardiogram or ECG is a diagnostic device that is used to monitor the electrical activity of the heart. The results are measured and displayed in the form of a graph on a monitor or are printed out on paper. These results can help to diagnose different abnormalities of the heart.

Reasons Why It is Conducted

An ECG test is normally done on someone who has been complaining of symptoms such as a pain or discomfort in the chest, palpitations, abdominal pain, nausea, and weakness. Any of these symptoms can be a sign of a problem with the heart. The ECG is also normally monitored during a surgical procedure to ensure that the heart is functioning normally.

The heart is divided into four compartments, namely, the right atrium, right ventricle, left atrium, and left ventricle. Blood enters into the right atrium after having travelled through the rest of the body. The right atrium then pushes the blood into the lungs where it is absorbs the oxygen from the air and releases carbon dioxide. The blood then enters the left atrium from where it is pumped into the left ventricle. The blood is then pumped back into the body's circulatory system from the left ventricle.

The heart beats almost 60 to 100 times a minute with the aid of its own natural pacemaker. This natural pacemaker is located in the right atrium and is called the sino atrial node or sinus node. The sinus node generates electrical signals that cause the contractions in the heart. The hearts natural pacemaker does not require the assistance of the brain for it to function and this is the reason why the heart still keeps beating even when the brain fails.

The electrical activity of the heart is displayed in the form of a graph with indicators called P, Q, R, S, and T. Atrial contractions are shown as P and ventricular contractions are show as Q, R, and S. The last wave called T indicates that the heart is repolarizing or getting ready for the next set of contractions.

How to Perform It?

To perform an ECG test, the doctor or nurse may ask the patient to lie flat on a bed. Twelve adhesive pads are then stuck to the body. Six of these pads are attached to the chest starting from the lower breastbone till the location below the left armpit. The remaining six are connected to the arms and legs. These pads are then attached to the ECG machine to take the electrocardiogram reading.

A normal electrocardiogram will show the P, Q, R, S, and T waves in a rhythmic, constantly repeating pattern that mimics the functioning of the heart. Any wave formation that deviates from this standard is an abnormal electrocardiogram and may indicate a variety of problems with the heart.

Taking an electrocardiogram reading is a simple and painless procedure that is most commonly used to analyze and identify problems that are related to the heart. A routine ECG check is recommended for people above the age of 35, to ensure that they are in good health.