ECG – Electrocardiogram
Today morning, I was to clinic and been advice to do ECG test. Thought in my mind, I never done it before and totally no idea about it. The nurse was telling me not to be afraid, not pain at all etc. The best advice to ask me to relax otherwise it will be affected the report. Even the nurse gives me some info of how it works. Therefore, the report done, and there is no symptom of heart decease.
Many thousands of people suffer from various conditions of the cardiovascular system including angina, high blood pressure and heart failure. Most adults will undergo an ECG examination at some stage in their adult lives. Therefore, it might be useful and interesting to know something about the test.
Today there are tens of thousands of electrocardiograms in use throughout the world. Although modern equipment may look a little different to the devices however the basic principles remain the same. The electrocardiogram detects and records the pattern of electrical activity in the heart and the pattern is recorded on special graph paper. This paper record is known as an electrocardiograph which I do have it this morning after the test.
Figure 1 (Sample of electrocardiograph)
Many people will have heard of artificial pacemakers but may not be aware that the heart has its own inbuilt pacemaker as well; this is referring to as the sino-atrial or SA node. This tiny structure emits an electrical impulse, which is conducted through the electrical conducting system of the heart. This electrical impulse stimulates the cardiac muscle to contract resulting in pumping of the blood through the chambers of the heart and out though the general circulation. The ECG detects and records this electrical activity and the tracing allows the doctor to reach certain conclusions regarding cardiac function.
ECGs are performed for a variety of reasons. A doctor may recommend an ECG in order to evaluate various symptoms such as chest pain or an irregular heart beat. Alternatively the test may be used to evaluate the state of heart in people with various risk factors such as high blood pressure and raised cholesterol levels. Sometimes it may be performed on people with no symptoms of the disease that happen to have a family history of heart disease. In some cases they may even be used as a form of reassurance in people who are anxious about the possibility of having heart disease. It happened to me, and the test to convince me as my healthy condition.
The ECG is useful for long term follow up of a person with known heart disease. One record can be compared with the next and indicate if significant change in cardiac function has happened in the interim. People with artificial pacemakers are well used to having regular ECGs in order to establish their artificial pacemaker is discharging effectively. Artificial pacemakers are fitted in situations where the SA node is faulty and not discharging properly.
The test can be performed in the surgery or at the hospital. It is important to realise that the test is painless and does not discharge any electricity into the person being examined. Rather it is measuring the low voltage electricity that is being discharged within the heart itself. It is customary for the person to strip to the waist for the examination. The person usually lies down for the test and a series of electrodes is applied to the wrists, ankles and chest. The electrodes act as sensors and a special jelly is applied to the skin, which helps to improve electrical conduction through the electrodes. The test takes less than ten minutes to perform.
Figure 2 - How a patient with connected to the 10 electrodes necessary for a 12-lead ECG
The ECG is a very useful diagnostic tool that is painless and patient friendly. It is quite likely that you will undergo this test some day, in which case you have absolutely nothing to fear from the test itself.
