During the cardiac cycle, the
A) P wave of the ECG occurs between the first and second heart sounds.
B) QRS complex of the ECG precedes the increase in ventricular pressure.
C) second heart sound occurs during atrial systole.
D) first heart sound coincides with the QRS complex of the ECG.
E) both QRS complex of the ECG precedes the increase in ventricular pressure and first heart sound coincides with the QRS complex of the ECG.

Question

Quizplus · Accepted Answer

The QRS complex represents ventricular depolarization, which leads to ventricular contraction and an increase in ventricular pressure. The first heart sound is associated with the closure of the atrioventricular valves, which occurs at the onset of ventricular systole, coinciding with the QRS complex.

During the Cardiac Cycle, the