Electrocardiogram Interpretation Concepts

What is the primary function of the sinoatrial (SA) node in the heart?

• To delay electrical impulses before they reach the ventricles.

• To initiate all heartbeats and determine heart rate.

• To conduct impulses to the Purkinje fibers.

• To repolarize the atria after contraction.

Why is there a delay in the passage of electrical impulses at the atrioventricular (AV) node?

• To allow the ventricles to fully repolarize.

• To ensure the atria have ejected all blood into the ventricles.

• To prevent premature ventricular contraction.

• To initiate the ventricular repolarization process.

What does the P wave on an electrocardiogram (ECG) signify?

• Ventricular contraction.

• Atrial repolarization.

• Ventricular relaxation.

• Atrial depolarization.

What physiological event is represented by the QRS complex on an electrocardiogram (ECG)?

• Atrial depolarization.

• Ventricular repolarization.

• Ventricular depolarization.

• Atrial repolarization.