Chapter 4 & 5

Question 0

Firing rate of the SA node

Answer 0

60-100 BPM

Question 1

Commonly referred to as the primary pacemaker of the heart because it normally depolarizes more rapidly than any other part of the conduction system

Answer 1

SA node (sinoatrial node)

Question 2

Distribute the electrical impulse throughout the atria and transmit the impulse from the SA node to the AV node

Answer 2

Internodal tracts

Question 3

A subdivision of the anterior internodal tract, conducts electrical activity from the SA node to the left atrium

Answer 3

Bachmann’s bundle

Question 4

Located on the floor of the right atrium near the coronary sinus and just above the tricuspid valve

Answer 4

AV node

Question 5

In the AV node electrical activity is delayed approximately

Answer 5

.05 seconds allows for more complete filling of ventricles

Question 6

The AV node is the secondary pacemaker and fires at

Answer 6

40-60 BPM

Question 7

Purkinje’s network firing rate is

Answer 7

20-40 BPM

Question 8

The region where the AV node joins the bundle of His

Answer 8

AV junction

Question 9

The pathway that leads out of the AV node and is also traditionally referred to as the common bundle

Answer 9

Bundle of His

Question 10

Two main branches,the right bundle and the left bundle. Conduct electrical activity from the bundle of His down into the Purkinje network

Answer 10

Bundle branches

Question 11

A network of fibers that carries electrical impulses directly to ventricular muscle cells

Answer 11

Purkinje’s network

Question 12

Normal conduction pattern of the heart

Answer 12

SA node, Internodal pathways, AV node, Bundle of His, Bundle branches, Purkinje fibers

Question 13

Placement of bipolar lead #1

Answer 13

Positive on left arm, negative on right arm

Question 14

Placement of bipolar lead #2

Answer 14

Positive on left leg, negative on right arm

Question 15

Placement of bipolar lead #3

Answer 15

Positive on left leg, negative on right arm

Question 16

Abnormal heart rhythms

Answer 16

Dysrhythmias

Question 17

Each small square represents _________ in height

Answer 17

1mm

Question 18

Each small square on a graph represents _________ seconds

Answer 18

.04

Question 19

A large box in the darker lines on the graph represent ____ seconds

Answer 19

.20

Question 20

The straight line seen on an EKG strip, represents the beginning and end point of all waves

Answer 20

Baseline

Question 21

Represents depolarization of the left and right atria

Answer 21

P wave

Question 22

Represents the time interval necessary for the impulse to travel from the SA node through the internodal pathways in the atria and downward to the ventricles

Answer 22

PR interval

Question 23

The P wave is approximately _________ in length

Answer 23

.10 seconds

Question 24

Normal PR interval is measured from the _________ to the ______________

Answer 24

Beginning of the P wave to the beginning of the QRS complex

Question 25

The normal PR interval is measured as __ to ___ small squares and is approximately ____ to _____ seconds in length

Answer 25

3 to 5 squares and .12 to .20 seconds

Question 26

Represents the conduction of the electrical impulse from the bundle of His throughout the ventricular muscle, or ventricular depolarization

Answer 26

QRS complex

Question 27

Normal QRS complex measures __________________ or _________________

Answer 27

Less than .12 seconds or less than three small squares on EKG paper

Question 28

The time interval during which the ventricles are depolarized and ventricular repolarization begins

Answer 28

ST segment

Question 29

Represents ventricular repolarization and follows the ST segment

Answer 29

T wave