Arrythmias

Question 1

Rhythm

Answer 1

Movement or procedure with uniform or patterned recurrence of a beat, accent, or the like

Question 2

Cardiac Arrhythmia

Answer 2

Heartbeat is irregular, too fast, or too slow

Question 3

What does the P wave represent?

Answer 3

Atrial depolarizaiton

Question 4

What does the QRS complex represent?

Answer 4

Ventricular depolarization

Question 5

What does the T wave represent?

Answer 5

Ventricular repolarization

Question 6

Contraction of the atria does what?

Answer 6

Moves blood into the ventricles

Question 7

Contraction of the right ventricle does what?

Answer 7

Sends O2 depleted blood to the lungs

Question 8

Contraction of the left ventricle does what?

Answer 8

Sends O2 rich blood to the body

Question 9

What coordinates cardiac muscle contraction?

Answer 9

Electrical signals

Question 10

Trace the circulation of blood through the heart

Answer 10

Vena cava –> R atrium –> R ventricle –> Pulmonary artery –> Lungs –> L atrium –> L ventricle –> Aorta –> rest of the body

Question 11

Trace the electrical current through through the conducting system through the heart

Answer 11

SA node –> AV node (signal pauses) –> AV bundle branches –> Purkinje fibers

Question 12

Where is the signaling velocity slowest in the heart?

Answer 12

AV node

Question 13

Where is the signaling velocity fastest in the heart?

Answer 13

Purkinje fibers

Question 14

What creates the EKG?

Answer 14

The sum total of action potentials traveling through the heart

Question 15

What does the PR interval describe?

Answer 15

The time it takes for the impulse to travel from the Sinus node through the AV node

Question 16

What does the ST segment represent?

Answer 16

The time the ventricles are depolarized

Question 17

What does the U wave represent?

Answer 17

Repolarization of the intraventricular septum

Question 18

What is the QT interval?

Answer 18

The speed of the heart beat

Question 19

What are the four main types of arrhythmias?

Answer 19

Extra beats
Supreaventricular tachycardias
Ventricular arrhythmias
Bardyarrhythmias

Question 20

Extra beat arrhythmia types

Answer 20

Premature atrial contraction

Premature ventricular contractions

Question 21

Supraventricular tachycardia types

Answer 21

Atrial fibrilation
Atrial flutter
Paroxysmal supraventricular tachycardia

Question 22

Ventricular arrhythmia types

Answer 22

Ventricular fibrilation

Ventricular tachycardia

Question 23

Bradyarrhythmias

Answer 23

Slow heartbeat

Question 24

What are the classifications of arrhythmias by site of origin?

Answer 24

Atrial
Ventricular
Juncitonal
AV Heart Blocks

Question 25

Atrioventricular Blocks

Answer 25

Conduction between the atria and ventricles is blocked or slowed Can be primary, secondary, tertiary

Question 26

Primary AV Block

Answer 26

PR interval is lengthened beyond 0.2 seconds

Question 27

Secondary AV block

Answer 27

Disturbance, delay, or interruption of atrial impulse conduction through the AV node to the ventricles

Question 28

Tertiary AV block

Answer 28

aka Complete heart block | Impulse generated in SA node does not propagate to the ventricles

Question 29

How will a primary AV block look on an EKG

Answer 29

PR interval is lengthened

Question 30

How will a secondary AV block look on an EKG

Answer 30

There will be QRS complexes dropped

Question 31

How will a tertiary AV block look on an EKG?

Answer 31

None of the p waves conduct to ventricles - P-P and QRS-QRS are independent

Question 32

What are the causes of arrhythmias?

Answer 32

Cardiac ischemia Excessive discharge or sensitivity to autonomic neurotransmitters Exposure to toxic substances (smoking, alcohol, Rx meds, caffeine, nicotine) Unknown etiology

Question 33

What occurs in phase 0 of cardiac action potential

Answer 33

Na goes into the cell (depolarization)

Question 34

What occurs in phase 1 of cardiac action potential?

Answer 34

K and Cl leave the cell

Question 35

What occurs in phase 2 of cardiac action potential?

Answer 35

Ca goes into the cell K goes out of the cell Plateau phase

Question 36

What occurs in phase 3 of the cardiac action potential?

Answer 36

K goes out of the cell | Repolarization

Question 37

What are the classes of Anti-Arrhythmic Drugs?

Answer 37

Class I Class II Class III Class IV

Question 38

Class I Anti-arrhythmic drugs

Answer 38

Block Na channels

Question 39

What are the different classes of Class I anti-arrhythmic drugs and when are they used?

Answer 39

Ia Ib Ic

Question 40

Class II Anti-arrhythmic drugs

Answer 40

B-adrenoceptor antagonists Diminish phase 4 depolarization - depressing automaticity, prolonging AV conduction, decreasing HR and contractility Can diminish both Na and Ca currents

Question 41

Class III Anti-arrhythmic drugs

Answer 41

K channel blockers Delay the ventricular AP (specifically repolarization) Prolong refractory period

Question 42

Class IV Anti-arrhythmic drugs

Answer 42

Ca channel antagonists Decrease Ca inward current, decreasing phase 4 spontaneous depolarization Slow conduction and increase the refractory period

Question 43

Ia Na channel blockers

Answer 43

Lengthen the duration of the AP Bind more selectively to the open state of the channel Dissociates from the channel with intermediate kinetics (1-10 seconds)

Question 44

Ib Na channel blockers

Answer 44

Shorten the duration of the AP Bind primarily to inactivated state of the channel Dissociates from the channel with rapid kinetics (

Question 45

Ic Na channel blockers

Answer 45

Minimal effect on the duration of the action potential Bind more selectively to the open state of the channel Dissociate from the channel with slow kinetics (>10 seconds)

Question 46

What are Class II Anti-arrhythmias used to treat?

Answer 46

Useful in treating tachyarrhythmias caused by increased sympathetic activity Also used for atrial flutter and fibrillation

Question 47

T/F - Class II and Class III compound, but Class I and Class III do not

Answer 47

True

Question 48

What are Class III Anti-arrhythmias used to treat?

Answer 48

Ventricular arrhythmias - especially ventricular fibrillation or tachycardia

Question 49

What phase of the Ventricular AP do Class I Anti-arrhythmic drugs effect?

Answer 49

Phase 0

Question 50

What phase of the Ventricular AP do Class II Anti-arrhythmic drugs effect?

Answer 50

Phase 4

Question 51

What phase of the Ventricular AP do Class III Anti-arrhythmic drugs effect?

Answer 51

Phase 3

Question 52

What phase of the Ventricular AP do Class IV Anti-arrhythmic drugs effect?

Answer 52

Phase 2