An EKG is a fast, painless test that measures the electrical activity of the heart, used by doctors in the diagnosis of heart conditions.
The Electricity of the Heart
The source of the electricity which the EKG detects is the heart's sinoatrial (SA) node.This node sends electrical signals to each of the four chambers of the heart, telling them when to beat.The electrical activity measured by an EKG then conforms to the performance of your heart.It tells your doctor at what rate your heart is beating, what size the chambers of your heart are and how each chamber is performing, and how healthy your heart muscle is.
Having an EKG: What to Expect
The test itself is painless, noninvasive, and quick.No special advance preparation is required, but do tell your doctor what medicines you are taking.You may need to remove your shirt, and if you have a great deal of body hair, it may be necessary to shave small areas.Up to twelve electrode patches will be placed on your skin- on your chest, and usually also your back and limbs- with an adhesive.These electrodes are connected to the EKG machine with insulated wires.Before the test, a technician will clean the areas where the patches will be placed.After they are attached, you will be instructed to lie down.The test itself lasts only for about a minute, during which time the machine produces a sketching of your heart's electrical activity.Your doctor may also order other tests, such as a chest x-ray or blood tests.The test is usually performed by a technician, but the results will be read by a doctor who specializes in interpreting EKGs.
After the traditional resting EKG described above, your doctor may order a stress EKG.In this case, your doctor will likely instruct you to abstain from eating, smoking, or drinking caffeinated beverages for two to four hours before the test.Dress comfortably and wear appropriate shoes.Electrodes will be attached as described above, but instead of lying down, you will be asked to walk on a treadmill as the speed and steepness increase, or to pedal a stationary bicycle as resistance gradually increases.The stress EKG allows your doctor to determine how your heart works when it must work harder than usual, as when you are exercising, and it helps in the diagnosis of certain diseases or problems which the resting EKG may not show.A resting EKG will always be performed before a stress EKG to help the doctor interpret the results of the stress EKG, and to make certain that it is safe for you to perform the stress EKG.
