Arrhythmias

Question 1

What are the problems in arrhythmias?

Answer 1

Rate: too fast, too slow (out of normal 60-100bpm)
Rhythm: how regular is the heart beat
Origin

Question 2

What are the causes of premature atrial contraction (PAC)?

Answer 2

Idiopathic
Toxins (smoking, ETOH, coffee)
ACS
COPD
Atrial myopathy

Question 3

PVC can be classified based on:

Answer 3

Morphology
Frequency
Symptomatic vs. asymptomatic
Exertional or not
Can underlying cause be identified

Question 4

What is atrioventricular first degree block?

Answer 4

Delay in transmission from atria to ventricles

Question 5

What is the most clinically significant heart block?

Answer 5

AV block

Question 6

What is atrioventricular second degree block?

Answer 6

Intermittent AV conduction

Question 7

What is another name for Mobitz type 1 second degree AV block?

Answer 7

Wenchebach

Question 8

What is occurring in Mobitz type 1 (Wenchebach) second degree AV block?

Answer 8

progressive prolongation until beat drop

Question 9

What is occurring in Mobitz type II second degree AV block?

Answer 9

Is maintained but will occasionally not conduct through to the ventricles (more dangerous because it isn’t predictable)

Question 10

What are the causes of second degree AV block?

Answer 10

MI involving/near the conduction system
Cardiomyopathy
Myocarditis
Endocarditis (abscess)

Question 11

Who is at high risk for endocarditis?

Answer 11

IV drug users

Question 12

What is occurring in third degree heart block?

Answer 12

complete heart block, no atrial impulses reach the ventricles, the atria and ventricles are no longer communicating (broke up) so firing in silos

Question 13

Why would someone in third degree block have pain?

Answer 13

Decreased oxygen being delivered to the heart

Question 14

If the patient has bunny ears on EKG what kind of heart block do they have?

Answer 14

Right bundle branch block (BBB)

Question 15

What is the most common tachyarrhythmia?

Answer 15

Sinus Tachycardia

Question 16

What kind of rhythm is seen in atrial fibrillation?

Answer 16

Irregularly irregular QRS complexes

Question 17

If the top chambers (atria) are beating in an irregular, uncontrolled manner (fibrilating) for long duration (past 48 hours) it can cause what?

Answer 17

Can cause a blood clot to form in the left atrial appendage

Question 18

What type of arrhythmia is sawtooth pattern pathoneumonic for?

Answer 18

Atrial Flutter

Question 19

What electrolyte is off balance in Torsades De Pointes?

Answer 19

Magnesium

Question 20

Do you have a pulse with ventricular fibrillation?

Answer 20

No

Question 21

What is occurring in ventricular fibrillation?

Answer 21

Chaotic depolarization of the ventricular myocardium, no true mechanical activation –> no cardiac output

Question 22

Decreased automaticity may cause

Answer 22

Bradyarrrhythmias

Question 23

What metabolic changes can cause bradyarrhythmias?

Answer 23

Hypothermia
Hypothyroidism (myedema coma)

Question 24

What is the pathophysiology of sick sinus dysfunction?

Answer 24

Fibrosis of the SA node
Medications
Familial disease -cardiac sodium channels SCN5A, HCN4

Question 25

What can be causes of sinus bradycardia?

Answer 25

Drugs (beta blockers, calcium channel blockers)
Conditioning (Fiore)
Birthday candles (age)

Question 26

What is the presentation of sinus bradycardia?

Answer 26

Asymptomatic
Fatigue, chronotropic incompetence (dyspnea on exertion)

Question 27

What are the EKG findings in Junctional Bradycardia?

Answer 27

• P-waves hidden within or after QRS
• Narrow QRS
• Typically slow: think about the AV node of 40-60bpm

Question 28

If AV junction has a faster firing rate than the SA node what will be the rhythm?

Answer 28

Junctional Rhythm - the AV is faster, so is beating the SA node

Question 29

What is asystole?

Answer 29

Complete absence of demonstrable electrical and mechanical cardiac activity

Question 30

What is the presentation of sinus node dysfunction?

Answer 30

• Asymptomatic at rest
• Exertional fatigue/DOE
• Unconscious (syncope)

Question 31

What is the management for sinus node dysfunction?

Answer 31

• Reversible causes (medications)
• Atropine
• Transcuatenous pacing vs. TVP via RIJ
• Pacemaker ?

Question 32

Anytime you have tachycardia what is the first line management?

Answer 32

Treat the reversible cause

(i.e. shock with antibiotics)

Question 33

In atrial fibrillation is the QRS still narrow?

Answer 33

Yes, it should be

Question 34

A CHAD Vascular Score of 2+ require what for treatment of their atrial fibrillation?

Answer 34

Anticoagulants to prevent stroke

Question 35

What is the treatment for a stable patient in aFib?

Answer 35

Anticoagulants (CHAD score 2+)
Rate Control
Rhythm control

Question 36

What are the anti-rhythmic classes that are used in aFib?

Answer 36

Class I (Na blockers) and III (K channel blocker)

Question 37

If a patient presents with tachycardia when bending down motions (picking up a laundry basket) what is the diagnosis until proven otherwise?

Answer 37

SVT

Question 38

What is an infection that can cause heart block?

Answer 38

Lyme carditis

Question 39

What is the mechanism of disease in heart block?

Answer 39

Disease of the AV node

Question 40

What are the presenting signs of heart block?

Answer 40

SOB
Lightheadedness
Syncope

Question 41

Why do you need to emergently treat ventricular tachyarrhythmias?

Answer 41

Can cause death

Question 42

What are the causes of ventricular tachyarrhythmias?

Answer 42

Ischemia/Infarct
Drugs
Toxicity
Metabolic derangements
Prolonged QTc

Question 43

What is the presentation of ventricular tachyarrhythmias?

Answer 43

Unconscious, pulseless
SOB, lightheadedness, palpitations

Question 44

What can cause premature complexes?

Answer 44

Excitable tissue
Catecholamines