An electrocardiogram (EKG or ECG) is a test that checks for problems with the electrical activity of your heart. An EKG shows the heart's electrical activity as line tracings on paper. The spikes and dips in the tracings are called waves. The heart is a muscular pump made up of four chambers . The two upper chambers are called atria. The two lower chambers are called ventricles.
http://www.webmd.com/heart-disease/electrocardiogram
Even so, the doctor might still want to do more tests. But it's important to understand that a normal stress test can't rule out the chance that a plaque will later rupture and block an artery—the proverbial tale of the man who passes a stress test with flying colors and then has a heart attack a week later.
http://www.health.harvard.edu/heart-disease-overview/cardiac-exercise-stress-testing-what-it-can-and-cannot-tell-you
If you have symptoms. For men with symptoms like chest pain with activity or unexplained shortness of breath, an abnormal stress test points to a higher risk of CAD. But it's more worrisome in a man who also has risk factors like older age, being overweight, or high cholesterol.
http://www.health.harvard.edu/heart-disease-overview/cardiac-exercise-stress-testing-what-it-can-and-cannot-tell-you
A Holter monitor records the heart's electrical activity for a full 24- or 48-hour period. You wear one while you do your normal daily activities. This allows the monitor to record your heart for a longer time than a standard EKG. An event monitor is similar to a Holter monitor.
http://www.medicinenet.com/pacemaker/page5.htm
Cardiac exercise stress testing: What it can and cannot tell you. This procedure helps determine your risk of heart disease, but follow-up testing is often required to be certain. Once it was common for a man middle-aged or older to get an annual exercise stress test to make sure his heart was still ticking like a fine watch. in case stress testing.
http://www.health.harvard.edu/heart-disease-overview/cardiac-exercise-stress-testing-what-it-can-and-cannot-tell-you
The readout of the EKG goes on points. P Q R S T : Waves Each segment defines an area of the heart that is contracting. For example P wave is the initial Atria activity. QRS is the activity in the lower ventricles and T is the relaxing of the muscle to rest.
http://www.answers.com/Q/What_does_an_EKG_show
In a stress test, you walk on a treadmill that makes your heart work progressively harder. An electrocardiogram (ECG) monitors your heart's electrical rhythms. The doctor also measures your blood pressure and monitors whether you have symptoms like chest discomfort or fatigue.
http://www.health.harvard.edu/heart-disease-overview/cardiac-exercise-stress-testing-what-it-can-and-cannot-tell-you
EKG (Electrocardiogram) An EKG is a simple, painless test that detects and records the heart's electrical activity. The test shows how fast your heart is beating and its rhythm (steady or irregular). An EKG also records the strength and timing of electrical signals as they pass through your heart. The test can help diagnose bradycardia and heart block (the most common reasons for needing a pacemaker).
http://www.medicinenet.com/pacemaker/page5.htm
This is why the EKG is useful as a diagnostic test. It is not, however, a perfect test and many innocuous conditions can cause abnormalities and an EKG can be normal even when there is serious pathology, which is why other tests are frequently necessary. Electrocardiogram records the electrical activity of your heart. An EKG (or electrocardiogram) is an electrical representation of the cardiac activity as detected by surface electrodes placed in specific locations across the chest and extremities. These electrodes detect the electrical activity occurring in the heart and these are depicted as deflections of a line.
http://www.answers.com/Q/What_does_an_EKG_show
An EKG is done to: 1  Check the heart's electrical activity. 2  Find the cause of unexplained chest pain or pressure. This could be caused by a heart attack, inflammation of the sac surrounding the heart (pericarditis), or angina.  Find the cause of symptoms of heart disease.
http://www.webmd.com/heart-disease/electrocardiogram
what does an ekg test reveal
An Electrocardiogram test reveals the problems with the electrical activity of your heart.