How many electrodes are used in a 12-lead EKG?

In a 12-lead EKG, ten electrodes are used to create twelve different leads. This includes the placement of six electrodes on the chest (precordial leads) and four limb electrodes. The limb electrodes are placed on the arms and legs, while the chest electrodes are positioned at specific anatomical sites across the thorax to capture the electrical activity of the heart from multiple angles.

The twelve leads provide a comprehensive view of the heart's electrical activity, enabling healthcare professionals to identify various conditions such as arrhythmias, ischemia, and other cardiac issues. Each lead gives a different perspective of the heart's electrical conduction, making the total significant for diagnostic purposes.