Question
In a standard ECG which one of the following alphabets is the correct representation of the respective activity of the human heart
S- start ofsystole
T- end of diastole
P- depolarisation of the atria
R - repolarisation of ventricles
Solution
C.
P- depolarisation of the atria
A normal electrogram (ECG) is composed of a P wave, a QRS wave (complex) and a T wave. The P-wave represents the electrical excitation or depolarization of the atria. The QRS complex represents the depolarization of the ventricles which initiates the ventricular contraction. The contraction starts shortly after Q and marks the beginning of the systole. The T-wave represents the repolarization of ventricles. The end of the T-wave marks the end of systole.
