Electrocardiography is a system of tracing graphically, the electric impulses generated by the heart muscles during a heartbeat. The graphic record is called electrocardiogram (ECG).
The working of the heart is regulated by electrical impulses. It’s each part including the various valves from where the blood flows in and out produces its own electric wave pattern. These electrical impulses are recorded by a machine called electrocardiograph.
Electrocardiogram provides extremely useful information regarding the condition and performance of the heart. It is very useful in the treatment of heart ailments.
Electrocardiograms are made by attaching electrodes to various parts of the body. These lead off the feeble heart current to the recording instrument. The four extremities and the chest become standard places for attaching the electrodes. When the electrocardiogram is switched on, an automatic pen recorder moves up and down on a chart paper and records each wave impulse.
The normal cardiogram shows typical upward and downward deflections that reflect the alternate contractions of the auricles (two upper chambers) and of the ventricles (two lower chambers) of the heart.
Variations in amplitude and direction of the current may give important information concerning the heart’s function and state of health. It can tell whether the heart is enlarged and where the enlargement occurs, whether the heart action is irregular and where the irregularity originates, whether a coronary vessel is occulted and where the occlusion is located or whether a slow rate is physiological or caused by the heart block. High blood pressure, thyroid disease and certain types of malnutrition may also be revealed by an electrocardiogram.
During the late 1960s, computerized ECGs came into use in many leading hospitals. These instruments directly tell the abnormalities of the heart muscle. Much advanced tests such as Trad Mill Test, Holter, Thallium stress tests etc are now available for finding the abnormalities of heart. Echo cardiography is also considered as an important diagnostic technique for heart disorders.
