Electrocardiogram Research

What is an electrocardiogram?
An electrocardiogram (EKG or ECG) is a test that checks for problems with the electrical activity of your heart. An EKG translates the heart's electrical activity into line tracings on paper. The spikes and dips in the line tracings are called waves.
What does an electrocardiogram do?
An electrocardiogram (ECG) measures the heart’s electrical activity to help evaluate its function and identify any problems that might exist. The ECG can help determine the rate and regularity of heartbeats, the size and position of the heart's chambers, and whether there is any damage present.
What does the graph tell?
The number of waves per minute on the graph is the heart rate.
The distance between these waves is the heart rhythm.
The shapes of the waves show how well the heart's electrical impulses are working, the size of the heart, and how well the individual components of the heart are working together.
The consistency of the waves provides relatively specific information about any heart damage present.
What does an electrocardiogram show?
EKG recordings can help doctors diagnose heart attacks that are in progress or have happened in the past. This is especially true if doctors can compare a current EKG recording to an older one.
An EKG also can show:
Lack of blood flow to the heart muscle (coronary heart disease)
A heartbeat that's too fast, too slow, or irregular (arrhythmia)
A heart that doesn't pump forcefully enough (heart failure)
Heart muscle that's too thick or parts of the heart that are too big (cardiomyopathy)
Birth defects in the heart (congenital heart defects)
Problems with the heart valves (heart valve disease)
Inflammation of the sac that surrounds the heart (pericarditis)

How Is an ECG Done?
There is nothing painful about getting an ECG. The patient is asked to lie down, and a series of small metal tabs (called electrodes) are fixed to the skin with sticky papers. These electrodes are placed in a standard pattern on the shoulders, the chest, the wrists, and the ankles. After the electrodes are in place, the person is asked to hold still and, perhaps, to hold his or her breath briefly while the heartbeats are recorded for a short period. The patient also might be asked to get up and exercise for a while.

When is an ECG (EKG) performed?
1. As part of a routine physical examination or screening evaluation.
2. As part of a cardiac exercise stress test.
3. As part of the evaluation of symptoms of chest pain, breath, dizziness or fainting, palpitations, or
4. As part of the preoperative workup for surgery in patients who may be at an age where heart disease could potentially be present.

Resources; http://www.nhlbi.nih.gov/health/health-topics/topics/ekg/show http://www.medicinenet.com/electrocardiogram_ecg_or_ekg/page2.htm#when_is_an_ecg_ekg_performed http://kidshealth.org/parent/general/sick/ekg.html