Which statement best describes why atrial depolarization is usually not detected on a normal ECG?
A)The electrodes cannot be placed high enough on the chest to detect the atria.
B)The atria do not contract only the AV valves open.
C)The voltage change in the atria is minimal and therefore does not register on an ECG.
D)It occurs at the same time as the QRS complex.
E)The atria are so small and the depolarization happens so quickly that it cannot be detected.

Question

Quizplus · Accepted Answer

Atrial depolarization is usually not detected on a normal ECG because it occurs at the same time as the QRS complex, which represents ventricular depolarization and is much larger, thus overshadowing the atrial signal.

Which Statement Best Describes Why Atrial Depolarization Is Usually Not