Many heart problems change the heart's electrical activity in distinct ways. An electrocardiogram (EKG) can help detect these heart problems.
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:
An EKG can reveal whether the heartbeat starts in the correct place in the heart. The test also shows how long it takes for electrical signals to travel through the heart. Delays in signal travel time may suggest heart block or long QT syndrome.
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