What term is also known as a sensor used to conduct electricity from the body to the electrocardiograph?

• A. Electrodes
• B. Leads
• C. Transducers
• D. Impedances

Answer: (A)

Electrodes are the sensor that sits at the skin–body interface to capture the heart’s electrical activity and deliver it to the electrocardiograph. They detect the electrical potentials generated by cardiac depolarization and, with the help of conductive gel or paste to reduce skin impedance, convert those ionic signals into electrical signals the ECG can record. Leads are simply the wiring and configurations that connect these sensors to the machine, while impedances describe the resistance at the skin–electrode contact that can affect signal quality. Although a transducer can describe devices that convert energy forms, the term most commonly used for the sensing element in an ECG setup is electrodes.