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"What do EKGs detect?"

ZocdocAnswersWhat do EKGs detect?


I am scheduled to have an EKG. What will it show the doctor?


An EKG is short for electrocardiogram. The test is performed by placing several "leads" (small stickers) on different parts of the chest wall and the extremities. The leads are connected to a monitor with electrical wires. The test is completely painless and completed in a matter of seconds. The monitor will display the electrical activity of the heart. It shows the doctor the voltages involved in the beating of the different chambers of the heart, and gives specific information about any abnormalities in the electrical conduction system of the heart. This can include suggestions of prior heart attacks, fast or slow conduction through different areas of the heart, and clues to the enlargement of specific chambers in the heart. The EKG also provides a snapshot of the type of heart rhythm and heart rate at the time of the test. EKG's are often used in the evaluation of chest pain because they can also show changes that suggest an active heart attack is underway, causing a lack of oxygen to certain areas of the heart, which is reflected on the EKG due to disturbances in the electrical conduction through those specific areas.

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