Chapter 8 : Normal Sinus Rhythm

Question 1

What are two things in common to all normal sinus rhythms?

Answer 1

All the P waves are identical

All the PR intervals are the same

Question 2

By definition, all of the sinus rhythms originate in the what node?

Answer 2

SA node

Question 3

The atrial rate in sinus bradycardia is what?

Answer 3

60 or below

Question 4

The atrial rate in sinus tachycardia is what?

Answer 4

100 or above

Question 5

The combined atrial vector points in NSR should point in what major direction?

Answer 5

Inferiorly

Question 6

In NSR, the P waves should always be upright in waht leads?

Answer 6

I, II, aVF

Question 7

The length of the PR interval should be what?

Answer 7

0.12 to 0.20 seconds

Question 8

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?

Answer 8

True

Question 9

During the PR interval, the atria, AV node, bundle of his, bundle branches, and purkinje system all fire?

Answer 9

True

Question 10

In NSR, the width of the QRS complex should be what?

Answer 10

0.06 to 0.11 seconds

Question 11

The absolute refractory period is that part of the cardiac cycle when another impulse may still be transmitted?

Answer 11

False

Question 12

During the relative refractory period , the myocardial tissue is in the process of repolarization. An early impulse occurring at this time may stimulate that heart and cause a contraction?

Answer 12

True

Question 13

Sometimes, circus pathways may form during the relative refractory period that can lead to complex arrhythmia formation?

Answer 13

True

Question 14

In NSR, the P-P interval should not be longer than what?

Answer 14

1 second or 5 big blocks