Final answer:
The electrocardiogram (ECG or EKG) records the cardiac electrical activity and specifically measures the vector voltage. The tool uses multiple electrodes attached to the chest, measuring voltages generated by the depolarization and repolarization waves within the heart. ECG readings signify different aspects of the heart's activity, providing information about its functioning.
Step-by-step explanation:
An electrocardiogram, also known as ECG or EKG, is a tool used to measure the electrical activity of the heart. To be more specific, the ECG records the cardiac electrical activity and specifically measures vector voltage.
The ECG works by attaching electrodes to specific areas on the chest. These electrodes measure the voltages generated by the depolarization and repolarization waves within the heart. Standard ECGs usually have 12 or more electrodes, but in the past, three-electrode ECGs were used, applied on the left and right arms and left leg. The voltage between the right arm and the left leg is called the lead II potential and is most commonly graphed to indicate heart muscle function.
The major features of an ECG each signify different aspects of the heart's activity. The P wave represents atrial depolarization, the QRS complex represents ventricular depolarization, and the T wave represents ventricular repolarization. Through these readings, an ECG provides significant information about the functioning and potential malfunctioning of the heart.
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