Final answer:
A 12-lead ECG requires 10 electrodes, with six placed on the chest and four on the limbs. These electrodes capture the heart's electrical activity and help diagnose cardiac conditions. Advances have made portable long-term monitoring possible.
Step-by-step explanation:
12-Lead Electrocardiogram and Electrode Placement
To perform a 12-lead electrocardiogram (ECG), a total of 10 electrodes are required. Six of these electrodes are placed on the chest, and four are placed on the limbs. The four limb electrodes are distributed as follows: one on each arm (right and left) and one on each leg (right and left). The six chest electrodes, referred to as V1 through V6, are placed in specific positions on the rib cage and over the heart to accurately capture the heart's electrical activity from multiple angles.
The ECG is an essential medical test that records the electrical activity of the heart using these electrodes. By capturing voltages between pairs of electrodes, the ECG provides a comprehensive view of heart function, which is critical for diagnosing various cardiac conditions.
Advancements in ECG technology have allowed for the creation of portable monitoring devices, such as the Holter monitor, which can continuously record heart activity over extended periods while the patient goes about their daily life.