Certified EkG technician (CET) Practice Exam

Which physiological event follows the P wave in normal cardiac activity?

1. Atrial contraction

2. Ventricular contraction

3. Ventricular depolarization

4. Atrial repolarization

The correct answer is: Atrial contraction

The physiological event that follows the P wave in normal cardiac activity is atrial contraction. The P wave on an electrocardiogram (ECG) represents the depolarization of the atria, leading to the contraction of these heart chambers. This contraction plays a crucial role in the cardiac cycle as it helps push blood from the atria into the ventricles, facilitating effective blood flow throughout the heart and into systemic circulation. Understanding this sequence is vital as it illustrates how electrical activation (depolarization) corresponds to mechanical activity (contraction), ensuring that the heart functions efficiently during each heartbeat. The events following the P wave, such as ventricular depolarization and contraction, occur later in the sequence and are represented by other components in the ECG, specifically the QRS complex. Thus, recognizing the significance of atrial contraction as a direct result of the P wave is key in analyzing cardiac rhythms and understanding overall heart function.