1. By definition, all of the sinus rhythms originate in the _________ node.
2. Which of the following are correct for normal sinus rhythm?
A. All the P waves are identical.
B. The P waves should all be positive in lead aVL.
C. The PR intervals should be identical.
D. An occasional interval that is much shorter than the others is considered normal.
3. The atrial rate in sinus bradycardia is _________ BPM.
4. The atrial rate in normal sinus rhythm is between _________ and _________ BPM.
5. The atrial rate in sinus tachycardia is _________ BPM.
6. The P wave is caused by the depolarization of the atria. The depolarization of the SA node, by itself, is electrocardiographically not visible. True or False.
7. The combined atrial vector points in NSR should point in which major direction (pick one):
A. Anteriorly
B. Posteriorly
C. Inferiorly
D. Superiorly
8. In NSR, the P waves should always be upright in leads _________, _________, and _________.
9. The length of the PR interval should be:
A. Less than 0.12 seconds
B. Between 0.10 and 0.20 seconds
C. Between 0.12 and 0.20 seconds
D. Greater than 0.20 seconds
10. The physiologic block is a normal slowing or delay of the impulse as it moves from the atria to the ventricles via the AV node. This slowing is critical to coordinate the mechanical contraction of the atria to the ventricles. Without the physiologic block, the atria and ventricles would contract simultaneously. True or False.
11. During the PR interval, the atria, AV node, bundle of His, bundle branches, and Purkinje system all fire. True or False.
12. In NSR, the width of the QRS complex should be:
A. Less than 0.06 seconds
B. Between 0.06 and 0.11 seconds
C. Between 0.10 and 0.12 seconds
D. Greater than 0.12 seconds
13. The absolute refractory period is that part of the cardiac cycle when another impulse may still be transmitted. True or False.
14. During the relative refractory period, the myocardial tissue is in the process of repolarization. An early impulse occurring at this time may stimulate the heart and cause a contraction. True or False.
15. Sometimes, circus pathways may form during the relative refractory period that can lead to complex arrhythmia formation. True or False.
16. Normal sinus rhythm is:
A. Regular
B. Regularly irregular
C. Irregularly irregular
D. An arrhythmia
17. Which of the following intervals should be the same in NSR?
A. PR interval
B. QRS interval
C. P-P interval
D. R-R interval
18. In NSR, the P-P interval should not be longer than ___ seconds or ___ big blocks on the ECG paper.
19. Very slight variations in the P-wave morphology and in the PR interval are considered acceptable in normal sinus rhythm. True or False.
20. The best lead to evaluate an arrhythmia in a particular patient is:
A. Lead I
B. Lead II
C. Lead V1
D. The best lead can vary from patient to patient.