Deck 2: Basic Electrophysiology

Question 1

The intrinsic rate of the atrioventricular (AV) bundle is _____ beats/min.

A) 20 to 40
B) 40 to 60
C) 60 to 80
D) 80 to 100

Answer 1

B
The AV bundle has pacemaker cells capable of firing at a rate of 40 to 60 beats/min.

Question 2

The intrinsic rate of the Purkinje fibers is _____ beats/min.

A) 20 to 40
B) 40 to 60
C) 60 to 100
D) 100 to 180

Answer 2

A
The Purkinje fibers have pacemaker cells capable of firing at a rate of 20 to 40 beats/min.

Question 3

Lead II records the difference in electrical potential between the _____ leg and _____ arm.

A) left; left
B) left; right
C) right; left
D) right; right

Answer 3

B
Lead II records the difference in electrical potential between the left leg and right arm electrodes. The positive electrode is placed on the left leg and the negative electrode is placed on the right arm. Lead II views the inferior surface of the left ventricle.

Question 4

In the heart's conduction system, the _____ receive(s) an electrical impulse from the bundle of His and relay(s) it to the Purkinje fibers in the ventricular myocardium.

A) atrioventricular (AV) node
B) atria
C) sinoatrial (SA) node
D) right and left bundle branches

Question 5

On an ECG, what is the first negative deflection seen after the P wave?

A) Q wave
B) R wave
C) S wave
D) T wave

Question 6

On the ECG, the T wave represents _____.

A) atrial contraction
B) atrial repolarization
C) ventricular contraction
D) ventricular repolarization

Question 7

The period during the cardiac cycle when cells cannot respond to a stimulus, no matter how strong, is called the _____ period.

A) depolarized
B) supranormal
C) relative refractory
D) absolute refractory

Question 8

Leads II, III, and aVF view the _____ surface of the left ventricle.

A) anterior
B) inferior
C) septal
D) lateral

Question 9

In the heart's conduction system, the _____ receive(s) an electrical impulse from the right and left bundle branches and relay(s) it to the ventricular myocardium.

A) AV node
B) SA node
C) Purkinje fibers
D) atrial pacemaker cells

Question 10

_____ is the ability of cardiac pacemaker cells to spontaneously initiate an electrical impulse without being stimulated from another source, such as a nerve.

A) Excitability
B) Conductivity
C) Automaticity
D) Contractility

Question 11

The normal pacemaker of the heart is the _____ node, which is found in the _____ atrium, and has an intrinsic firing rate of _____ beats/min.

A) sinoatrial; left; 40 to 60
B) sinoatrial; right; 60 to 100
C) atrioventricular; left; 20 to 40
D) atrioventricular; right; 100 to 180

Question 12

How do you determine whether the atrial rhythm on an ECG tracing is regular or irregular?

A) Compare QT intervals.
B) Compare PR intervals.
C) Compare R to R intervals.
D) Compare P to P intervals.

Question 13

On the ECG, the time necessary for the spread of an electrical impulse through the AV node, bundle of His, right and left bundle branches, and the Purkinje fibers is reflected by the _____.

A) TP segment
B) PR segment
C) QT interval
D) QRS duration

Question 14

The absolute refractory period begins with the onset of the _____ and terminates _____.

A) P wave; with the end of the QRS complex
B) QRS complex; at approximately the apex of the T wave
C) QRS complex; with the end of the T wave
D) P wave; with the beginning of the QRS complex

Question 15

In an adult, the normal duration of the QRS complex is _____.

A) 0.12 to 0.20 second
B) 0.10 second or less
C) 0.04 to 0.14 second
D) 0.20 second or less

Question 16

The intrinsic rate of the SA node is _____ beats/min.

A) 40 to 60
B) 60 to 100
C) 100 to 180
D) 200 to 260

Question 17

Leads I, aVL, V?, and V? view the _____ surface of the left ventricle.

A) anterior
B) septal
C) inferior
D) lateral

Question 18

In most patients, the sinoatrial (SA) and atrioventricular (AV) nodes are supplied by the _____ coronary artery.

A) right
B) left main
C) circumflex
D) left anterior descending

Question 19

The QT interval is measured from the beginning of the _____.

A) QRS complex to the end of the T wave
B) P wave to the end of the QRS complex
C) QRS complex to the beginning of the T wave
D) P wave to the beginning of the QRS complex

Question 20

What does the QRS complex represent?

A) Atrial depolarization
B) Ventricular contraction
C) Ventricular repolarization
D) Ventricular depolarization

Question 21

A conduction problem above the level of the bundle branches will largely affect the P wave and PR interval.

Question 22

The period of time during the cardiac cycle when cells cannot respond to a stimulus, no matter how strong, is the relative refractory period.

Question 23

In most ECG leads, a normal Q wave is less than 0.04 second in duration and less than one third the amplitude of the R wave in that lead.

Question 24

The portion of the ECG tracing between the QRS complex and the T wave is called the ____.

A) PR segment
B) ST segment
C) TP segment
D) QT interval

Question 25

Name the first positive deflection seen after the P wave on the ECG.

Question 26

The PR interval is considered prolonged if it is more than _____ seconds in duration.

A) 0.06
B) 0.12
C) 0.18
D) 0.20

Question 27

When the cardiac muscle cell is stimulated, the cell is said to _____.

A) polarize
B) recover
C) depolarize
D) repolarize

Question 28

An ECG lead that has a positive and negative electrode is called a(n) _____ lead.

Question 29

The appearance of coved ("frowny face") ST-segment elevation is called a(n) _______________.

Question 30

On the ECG, the P wave represents atrial _____ and the QRS complex represents ventricular _____.

A) depolarization; depolarization
B) repolarization; repolarization
C) repolarization; depolarization
D) depolarization; repolarization

Question 31

A line between waveforms is called a(n) _____.

Question 32

Tall, peaked T waves observed on the ECG are most commonly seen in patients with _____.

A) hypokalemia
B) hyperkalemia
C) hyponatremia
D) hypernatremia

Question 33

Which part of the conduction system receives an impulse from the bundle of His and relays it to the Purkinje fibers?

A) SA node
B) AV node
C) Right and left atria
D) Right and left bundle branches

Question 34

Which of the following correctly reflects examples of ectopic (latent) pacemakers?

A) The SA node and AV junction
B) The AV junction and ventricles
C) The SA node and right bundle branch
D) The AV junction and left bundle branch

Question 35

The cells of the heart that contain contractile filaments are called _____ cells.

Question 36

_____ is the ability of cardiac cells to spontaneously initiate an electrical impulse without being stimulated from another source.

Question 37

Which of the following is the first positive deflection seen on the ECG after the P wave?

A) Q wave
B) R wave
C) S wave
D) T wave

Question 38

Depolarization is the same as contraction.

Question 39

_____ is a term used to describe the period of recovery that cells need after being discharged before they are able to respond to a stimulus.

A) Irritability
B) Conductivity
C) Polarization
D) Refractoriness

Question 40

_____ cells are working cells of the heart that contain contractile filaments and form the muscular layer of the atrial walls and the thicker muscular layer of the ventricular walls.

A) Pacemaker
B) Myocardial
C) Specialized
D) Electrical

Question 41

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
The QRS complex represents _____ depolarization.

Question 42

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
An ECG machine is a sophisticated _____.

Question 43

The point where the QRS complex and the ST segment meet is called the ST junction or J-point.

Question 44

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
ECG changes observed in leads that look directly at the affected area of the heart

Question 45

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
Element or compound that breaks into charged particles (ions) when melted or dissolved in water or another solvent

Question 46

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
The T wave represents ventricular _____.

Question 47

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
The spread of an impulse through tissue already stimulated by that same impulse

Question 48

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
Height (voltage) of a waveform on the ECG

Question 49

Explain the significance of Einthoven's triangle.

Question 50

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
The P wave represents _____ depolarization.

Question 51

In the limb leads, the ST segment is normally isoelectric, or less than 1 mm above or below the isoelectric line.

Question 52

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
ECG changes observed in leads opposite the affected area of the heart; also called mirror image changes

Question 53

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
The a in aVR, aVL, and aVF

Question 54

On the ECG, what do the ST segment and T wave represent?

Question 55

If the wave of depolarization (electrical impulse) moves toward the positive electrode, the waveform recorded on ECG graph paper will be upright (positive deflection).

Question 56

Complete the following chart:

Question 57

Complete the following chart:

Question 58

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
Impulse(s) originating from a source other than the SA node

Question 59

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
During this period, a weaker than normal stimulus can cause depolarization of cardiac cells.

Question 60

Match each item to the correct description below.
a.Ventricular
b.Atrial
c.Repolarization
d.Augmented
e.Reciprocal changes
f.Indicative changes
g.Reentry
h.Ectopic
i.Positive
j.Amplitude
k.Voltmeter
l.Supranormal
m.Electrolyte
Each electrode placed in a "V" position is a(n) _____ electrode.

Question 61

List four major electrolytes that influence cardiac function.

Question 62

List the ECG leads that view the heart in the horizontal plane, allowing a view of the front and left sides of the heart.

Question 63

Is depolarization the same as contraction? Explain your answer.

Question 64

List three causes of artifact on an ECG tracing.

Question 65

Generally speaking, what is the normal duration of a QT interval?