How much voltage is represented by 10mm on the vertical axis of an ECG tracing?

In an ECG tracing, the vertical axis represents voltage. Each 10mm deflection typically corresponds to a specific millivolt increment. Standard calibration for ECGs often specifies that a 10mm deflection equals 1 millivolt. This means that if a point on the ECG tracing moves up by 10mm, it reflects an increase of 1 millivolt in electrical activity.

This standardization is critical for interpreting the ECG, as it allows healthcare providers to quantify the electrical impulses that the heart generates and assess any abnormalities in heart function. Therefore, recognizing that 10mm on the vertical axis represents 1 millivolt is essential for accurate readings and clinical decisions based on the ECG.