What is the noninvasive procedure used to detect the heart's electrical activity?

• A. Electrocardiography
• B. Electrocardiogram
• C. Holter monitor
• D. Electrodes

Answer: (A)

This item tests understanding of how the heart’s electrical activity is measured noninvasively. The standard procedure for recording the heart’s electrical signals is electrocardiography, which uses electrodes placed on the skin to pick up the electrical impulses and sends them to a machine that creates a tracing. That tracing, the electrocardiogram, shows the timing and pattern of the heartbeats and is used to identify rhythm problems, ischemia, or injury. So electrocardiography is the process itself, while an electrocardiogram is the resulting recording. A Holter monitor is a portable device used for extended ECG recording over a day or more, not the general procedure name, and electrodes are the sensors placed on the skin, not the procedure.