Electrocardiography is a medical technique by which minute electrical impulses, related to the functioning of the heart muscle, are detected, recorded, and printed out over time for interpretation by doctors. It is the best way to detect, diagnose, and determine the severity of many heart problems, mostly involving abnormal heart rhythms. It is also useful for detecting certain types of heart damage, murmurs, and circulatory problems.
The term electrocardiography is derived from three Greek words relating to electricity, the heart, and writing. The printout of data obtained from electrocardiography is called an electrocardiogram and is often abbreviated as ECG or EKG. Many doctors and health professionals prefer EKG as it helps prevent confusion with another type of medical process called an electroencephalogram or EEG.
A patient being examined by electrocardiography is fitted with a number of skin electrodes, sensors which can detect the minute electrical impulses of the human body. These electrodes are placed at various points on the body, mostly on the chest, but also at each wrist and ankle. They transmit the electrical impulses generated by the operation of the heart and circulatory system back to a central unit that interprets the data and prints it out in a continuous, real-time format on paper. Many machines also have a digital display and recording capability.
A doctor can study the data on an EKG and use it to diagnose and detect irregular heart rhythms, certain types of heart damage, and other circulatory problems. An EKG is especially useful for diagnosing damage due to myocardial infarctions, commonly known as heart attacks. Patients believed to have suffered a heart attack or in danger of an imminent heart attack are nearly always hooked up to an electrocardiography machine as soon as they come under medical care.
Doctors rely on electrocardiography to give them much information that would be unavailable without surgery or more invasive procedures. A skilled cardiologist, or doctor that specializes in treating heart problems, can obtain a great deal of information about a patient's heart and circulatory system through electrocardiography. Even certain genetic abnormalities or the presence of some types of drugs may be detectable through EKG analysis.
An EKG is often used as a monitoring tool for patients with heart or circulatory problems, in addition to its use as a diagnostic tool. It is not uncommon for these types of patients to be connected to an EKG machine for extended periods while under care or treatment for these types of issues. Alarms may be programmed to alert doctors to potential problems that may arise with these patients while connected to one of these machines.