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ECG 101: Understanding the Lifesaving Diagnostic Tool

Electrocardiograms, also referred to as ECGs or EKGs, help doctors discover heart problems by monitoring the electrical activity of the heart. ECG machines provide critical information to doctors, which they can use to promote the early detection and treatment of heart disease. As heart disease is a major killer in the U.S., the ECG machine is an important tool in promoting the health and wellbeing of Americans.

Lifesaving Diagnostic Tool

The very first ECG device was invented in 1903 by German scientist Willem Einthoven. Einthoven won a Nobel Prize in 1924 for his work on the device, and much of his original work remains relevant to medical care and treatment today, especially since ECGS are now commonly used to diagnose heart problems. About 75 million are performed in the U.S. each year. The worldwide number of ECGs performed yearly is estimated to total about 150 million. Although there has been some recent criticism of overuse of ECGs, no one who has ever had a heart condition detected and treated thanks to ECGs would agree.

Heart disease is one of the leading causes of death in the U.S., resulting in the deaths of more than 600,000 people annually. Heart disease is also a major cost for individuals and the health care system as a whole, representing more than $108 billion each year in treatment costs and lost wages and productivity. Men are more likely to suffer from heart disease, and the illness is more prevalent in the South than other parts of the country.

How ECGs Work

The heart is a large muscle consisting of four chambers – two upper chambers called atria and two lower chambers known as ventricles. The heart has a natural electrical system called the sinus node that sends pulses causing the heart to contract and pump blood through the body.

An ECG machine monitors the electrical pulses and represents them as line tracings on paper or a digital display. Trained cardiologists can observe these tracings and diagnose possible problems with the heart.

The ECG uses electrodes placed on various parts of the body to monitor the electrical activity of the heart. The standard ECG uses 10 electrode leads – one on each arm and leg and then six across the chest. Signals detected by the electrode lead are recorded by the ECG machine. Much of the helpfulness and accuracy of ECG findings depends on the medical professionals conducting the test and analyzing the results, so finding highly qualified doctors and technicians to perform the test is important.

Why Doctors Order an ECG

Physicians may order an ECG for a variety of reasons, including:

  • Monitoring the electrical activity of the heart
  • Discovering why a patient may be having chest pains
  • Determining whether symptoms of heart disease such as dizziness, fainting, palpitations, or shortness of breath are being caused by heart disease or are signs of another illness
  • Determining whether the heart chambers’ walls have become hypertrophied
  • Monitoring the progress of medications in treating heart disease
  • Monitoring the effectiveness of pacemakers
  • Monitoring how medications prescribed for other illnesses are affecting the heart
  • Checking on heart health for sufferers of high blood pressure, diabetes, high cholesterol, or other ills.

Often, when patients check into a hospital or emergency room after experiencing chest pains, an ECG will be ordered to determine whether that patient has experienced a heart attack. Even if a heart attack has not occurred, an ECG machine will help doctors determine whether patients are experiencing pain because of angina or atherosclerosis. Often initial ECGs may not detect abnormal activity, but serial ECGs conducted over a brief interval will discover heart conditions.

In recent years, doctors have prescribed regular ECGs to older patients. Doctors assert that regular screening using ECGs will help detect heart problems early, allowing for more effective interventions by physicians.

Preparing for an ECG

To prepare for an ECG test, patients should provide full disclosure to their doctors regarding any medications they may be taking. Some medications may influence the results of the test, and doctors need to be aware of these factors to properly interpret the information provided by the ECG.

When getting ready for the test, patients will need to take off any jewelry they may be wearing. In most cases, men will be bare-chested during an ECG and women typically wear a bra, t-shirt, or hospital gown.

The Test

During the test, patients will lie on a table or bed. Medical personnel performing the test will clean the areas of the patient’s arms, legs, and chest where the electrode leads will be placed. Personnel may shave some of these areas. To improve conduction, medical personnel may place a special ECG gel on patients’ skin where the ECG leads will touch.

Once the patient has been prepared, a doctor or nurse will attach the electrode leads to the skin. The ECG machine will be activated and the test will begin. If an older machine is being used, medical personnel may move the electrodes a few times during the test.

Patients will be asked to keep still and breathe normally during the ECG test. There are no risks associated with the test and it usually takes just five to 10 minutes to perform.

With the information gathered from an ECG, doctors will develop treatments for possible heart conditions. These treatments may consist of changes to diet and physical activity, medications and, in some cases, surgery.

Last Word

ECG tests are commonly ordered by doctors because they are fast, relatively inexpensive, and capable of diagnosing a variety of cardiac problems. ECG machines are not infallible – certain disturbances and other factors may skew the results of a test and inexpertly trained medical professionals may not accurately interpret the results. Working with highly qualified medical personnel who use trustworthy ECG machines by reliable providers like Medical Device Depot can help improve patients’ chances of obtaining accurate, actionable information concerning their health.

Sources:

http://www.cardiology.org/recentpapers/ecgrev.pdf
http://www.medcan.com/articles/the_benefits_and_limitations_of_electrocardiography/
http://www.emedicinehealth.com/electrocardiogram_ecg/article_em.htm
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