Cardiac Arrhythmias Flashcards Preview

JL Cardiovascular > Cardiac Arrhythmias > Flashcards

Flashcards in Cardiac Arrhythmias Deck (135)
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1

Where is the origin in a supraventricular arrythmia?

Above ventricle i.e. SA, atrial muscle, AV node or HIS node

2

What are ectopic beats?

Beats or rhythms that originate in places other than the SA node

3

Whta may cause single beats or take over and pace the heart, dictating its entire rhythm?

Ectopic focus

4

Name three supraventricular tachycardias?

1. Atrial fibrillation
2. Atrial flutter
3. Ectopic atrial tachycardia

5

Name two bradycardia (supraventricular arrhythmias)?

1. Sinus bradycardia
2. Sinus pauses

6

Name three atrio-ventricular node arrythmias?

1. AVN re-entry
2. Acessory pathway (e.g. WPW)
3. AV block - 1st, 2nd and 3rd degree

7

Name 4 ventricular arrythmias?

1. Premature ventricular complex (PVC)
2. Ventricular tachycardia
3. Ventricular fibrillation
4. Asystole

8

What can abnormal anatomy e.g. left ventricular hypertrophy, accessory pathways and congenital HD cause?

Arrythmias

9

What are two autonomic causes of arrythmias?

1. Sympathetic stimulation - nervousness, exercise, CHF, hyperthyroid
2. Increased vagal tone (bradycardia, heart block)

10

What are three metabolic causes of arrythmias?

1. Hypoxic myocardium: chronic pulmonary disease, PE
2. Ischaemic myocardium: acute MI, angina
3. Electrolye imbalances: imbalances of K, Ca, Mg

11

What inflammation cause is there of arrythmias?

Viral myocarditis

12

Name a mutation of cardiac ion channels that can cause arrythmias?

The congenital long QT syndrome

13

What two conditions can alter automacitiy?

Ischaemia and catecholamines

14

What two things can cause re-entry?

WPW syndrome - accessory pathway tachycardia
Previous MI

15

What does hypothermia do to phase 4 slope?

Decreases it

16

What do hypoxia and hypercapnia do to phase 4 slope?

Increase it

17

What does cardiac dilatation do to phase 4 slope?

Increases it

18

What increases automaticity of neighbouring cells?

Local areas of ischaemia or necrosis

19

Whay does hypokalaemia do to phase 4 slope?

Increases it and also increases ectopics, prolongs repolarisation

20

What is the term for: in the terminal phase of AP (phase 3), a small depolarisation may occur (called an after depolarisation), and if of sufficient magnitute may reach threshold and lead to a sustained train of depolarisations

Triggered activity

21

What mechanism underlyes digoxin toxicity, Torsades de Pointes in long QT syndrome and hypokalaemia?

Triggered activity

22

What requires available circuit, unidirectional block, and different conduction speed in limbs of circuit?

Re-entry

23

Where is the origin in a ventricular arrhythmia?

Ventricle

24

What type of conditions promote functional block?

Conditions that depress conduction velocity or shorten refractory period promote functional block

25

What are four main investigations you would do for arrythmias?

1. 12 lead ECG
2. CXR
3. Echocardiogram
4. Stress ECG

26

What are signs on an ECG of a previous MI?

Q waves

27

What does pre-excitation suggest, when seen on an ECG?

Wolf Parkinson White syndrome

28

What investigation can assess for ischaemia and excersise induced arrythmias?

Exercise ECG

29

What investigation is used to assess for paroxysmal arrythmia?

24hr Holter ECG

30

What investigation can assess for structural disease? (e.g. enlarged atria ain AF, LV dilatation or previous MI scar, aneurysm)

Echo

31

What study triggers arrythmia to study its mechanism and gives an opportunity to treat the arrythmia by radiofrequency ablation?

Electrophysiological study

32

What condition can be asymptomatic, palpitations, there is generally no treatment, b-adrenergic blockers may help and you need to avoid stimulants like caffeine?

Atrial ectopic beats

33

What type of STEMI is bradycardia related ischaemia common in?

Inferior STEMIs

34

What are the two treatment options for sinus bradycardia?

1. Atropine (if acute)
2. Pacing if: haemodynamic compromise such as hypotension, CHF, angina or collapse

35

What drugs can be used to treat sinus tachycardia?

1. B-adrenergic blockers

36

16 year old girl, fast palpitations, alert, no distress, good colour, HR very fast and normal physical exam?

Narrow complex tachycardia, SVT

37

What three things may supra-ventricular tachycardia be due to?

1. AV nodal re-entrant tachycardia
2. Accessory pathway tachycardia i.e. Wolff Parkinson White syndrome
3. Ectopic atrial tachycardia

38

What would you do as initial emergency treatment for an infant with SVT?

Peds vagal maneovres

39

What emergency initial step would you do for a child with SVT?

Blow through straw or carotid massage

40

What emergency step would you do for an adult with AVT?

Carotid sinus massage

41

For management of supra-ventricular tachycardia, what would you give after you have performed vagal manoeuvres, carotid massage?

IV adenosine
IV verapamil

42

What 3 steps of chronic management for SVTs are there?

1. Avoid stimulants
2. Radiofrequency ablation
3. Antiarrythmic drugs (Class II or IV)

43

What is selective cautery of cardiac tissue to prevent tachycardia, targeting either an automatic focus or part of a re-entry circuit?

Ablation

44

What three steps are involved in ablation?

1. Catheters placed in heart via femoral veins
2. Intracardiac ECG recorded during sinus rhythm, tachycardia and during pacing manoeuvres
3. Catheter placed over focus/pathway and tip heated to 55-65C

45

What investigation shows the activation sequence of the heart and has more detail than a surface ECG?

Intracardiac ECG

46

What type of arrythmic disease can ageing, acute MIs, myocarditis and infiltrative disease (amyloid) cause?

AVN conduction disease

47

What two classes of drugs cause AVN conduction disease?

B-blockers
Calcium channel blockers

48

What two genetic causes are there of AVN conduction disease?

Lenergre's disease
Myotonic dystrophy

49

Can calcific aortic valve disease and post-aortic valve surgery lead to AVN conduction disease?

Yes

50

In first degree AV block, what is the PR interval like?

Longer than >0.2 seconds

51

What is the treatment for first degree AV block?

None

52

What degree of block is an intermittent block at the AVN (dropped beats)?

2nd degree AV block

53

What are the two types of 2nd degree AV block?

Mobitz I
Mobitz II

54

Give two features of Mobitz type I 2nd degree AV block?

1. Progressive lengthening of the PR interval, eventually resulting in a dropped beat
2. Usually vagal in tone

55

Give three features of Mobitz II, 2nd degree AV block?

1. Pathological, may progress to complete heart block (3rd degree HB)
2. Usually 2:1, or 3:1, but may be variable
3. Permanent pacemaker indicated

56

In 2nd degree AV block, Mobitz II what do some action potentials fail to do?

Get through the AV node

57

What is the treatment for 2nd degree AV block Mobitz type II?

Ventricular pacing

58

What can be said about hte action potentials in 3rd degree AV block?

No action potentials from the SA node/atria get through the AV node

59

What is the treatment for 3rd degree AV block?

Ventricular pacing

60

What are two options for acute pacing?

1. Transcutaneous pacer
2. Transvenous pacer

61

What two types of pacemakers are there?

1. Single chamber (paces the right atria or right ventricle only)
2. Dual chamber (paces the RA and RV)

62

When are atrial pacemakers used?

In isolated SA node disease but normal AV node

63

When are ventricular pacemakers used?

In AF with slow ventricualr rate

64

What pacemakers maintain AV synchrony and are used for AVN dsiease?

Dual chamber

65

What might premature ventricular ectopics be a marker for?

Inherited arrhythmia syndromes e.g. cardiomyopathy

66

What happens to the atrial pressure in ventricular tachycardia?

Large, sustained reduction

67

What two conditions do most patients have before getting ventricular tachycardia?

Coronary artery disease and previous MI

68

What are two inherited/familial arrhythmia syndromes that can cause ventricular tachycardia?

1. Long QT
2. Brugada syndrome

69

What can rates range from in ventricular tachycardia?

110-250bpm

70

What are these ECG findings characteristic of: QRS complexes are rapid, wide and distorted, T waves are large with deflections opposite the QRS complexes, ventricular rhythm is usually regular, P waves are usually not visible, PR interval is not measurable, AV dissociation may be present, VA condution may or may not be present?

Ventricular Tachycardia

71

What arrythmia is chaotic ventricular electrical activity which causes the heart to lose the ability to function as a pump?

Ventricular fibrillation

72

What are the two treatment methods for ventricular fibrillation?

Defibrillation
Cardiopulmonary resuscitation

73

What are two acute treatment options for VT?

1. DC cardioversion if unstable
2. If stable consider pharmacologic cardioversion with AAD

74

What do sotalol, quinidine, terfenadine and erythromycin do to the QT interval?

Prolong it

75

What are three causes of VT?

1. Hypokalaemia, hypomagnesaemia
2. Ischaemia
3. Hypoxia

76

For a monomorphic stable VT, what 4 drugs would you administer?

1. IV procainamide
2. IV sotalol
3. IV amiodarone
4. IV beta blockers

77

What can you implant if life threatening VT is there long term?

Implantable cardiovertor defibrillator (ICD)

78

What two arrythmias are life threatening?

VT and VF

79

What do most ventricular arrythmias occur in the setting of?

Structural heart disease

80

60 female, hypertension for years, palpitations, SOB, fatigue, on enalapril, irregularly irregular pulse?

Atrial fibrillation & LVH

81

What is the atrial activity like in AF?

Chaotic and disorganised

82

What three things can AF be defined as either?

1. Paroxysmal
2. Persistnet
3. Permanent

83

Give two features of paroxysmal AF?

1. Paroxysmal and lasting less than 48 hours
2. Often recurrent

84

Give two features of persistent AF?

1. An episode of AF lasting greater than 48 hours, which can still be cardioverted to NSR
2. Unlikely to spontaneously revert to NSR

85

Give one feature of permanent AF?

Inability of pharmacological or non-pharmacologic methods to restore NSR

86

What are hypertension, congestive heart failure, sick sinus syndrome, coronary heart disease, thyroid disease, familial and valvular heart disease all causes of?

AF

87

What are COPD, pneumonia, septicaemia, pericarditis and tumours all causes of?

AF

88

What occurs in the absence of any heart disease and no evidence of ventricular dysfunction, a diagnosis of exclusion?

Lone/idiopathic AF

89

Give 5 symptoms of AF?

1. Palpitations and chest pain
2. Pre-syncope dizziness and syncope
3. Dyspnea
4. Sweatiness
5. Fatigue

90

Give two features of the mechanism of AF?

1. Multiple wavelets of reentry
2. Ectopic focus around the pulmonary veins

91

Give three terminations of AF?

1. Pharmacologic cardioversion with anti-arrythmic drugs
2. Electrical cardioversion
3. Spontaneous reversion to sinus rhythm

92

What three drugs can terminate and prevent AF?

1. Flecainide
2. Sotalol
3. Amiodarone

93

What is the atrial rate and rythm of an ECG in AF?

1. Atrial rate > 300bpm
2. Rhythm: irregularly irregular

94

What three things is the ventricular rate on ECG in AF dependent upon?

1. AV node conduction properties
2. Sympahtetic and parasympathetic tone
3. Presence of drugs with act on the AV node

95

What is there the absence of P waves and the presence of "f" waves in?

AF

96

What two classes of drugs decrease conduction in the AV node and are useful in controlling ventricular rate during AF?

Beta-blockers
Calcium channel blockers

97

For patients with hypertrophic cardiomyopathy, what can loss of atrial kick and decreased filling times result in?

Congestive heart failure

98

What can patients with pre-excitation (Wolff-Parkinson-White Syndrome) result in?

Ventricular fibrillation and sudden cardiac death

99

What in AF does lost 'atrial kick' and decreased filling times (reduced diastole) lead to?

Reduced cardiac output

100

What two approaches of management are there for AF?

Rhythm control - maintain SR predominantly
Rate control - accept AF but control ventricular rate

101

If there is a high risk for thromboembolism for both rhythm control and rate control, what should be done?

Anticoagulation

102

During rate control in AF, what 4 pharmacological therapies are there to slow down AVN conduction?

1. Digoxin
2. Betablockers
3. Verapamol
4. Diltiazem

103

During rhythm control of AF, what two methods are there for restoring NSR?

1. Pharmacologic cardioversion (anti-arrythmic drugs e.g. amiodarone)
2. Direct current cardioversion (DCCV)

104

What three methods are there for rhythm control - maintainence of NSR in AF?

1. Anti-arrythmic drugs
2. Catheter ablation of atrial focus/pulmonary veins

3. Surgery (maze procedure)

105

What do flecainid, sotalol and amiodarone do to AF rythm?

Maintain sinus rhythm

106

During an episode of AF, what can immediatly restore normal sinus rhythm?

Electrical cardioversion

107

How do anti-arrythmic drugs act?

Through electrophysiological mechanisms by blocking the ionic currents across cell membranes that create the action potentials

108

What channel block, action potential phase and main use in AF are for Class I anti-arrythmic drugs?

Channel blocked: Na+
Action potential phase: 0
Main uses in AF: Rythm control

109

What class of anti-arrythmic drugs are flecainide and propafenone?

Class I

110

What are channels blocked, action potential phase and main uses in AF for class II anti-arrythmic drugs?

Channels blocked: beta-receptors
Action potential phase: 4
Main uses in AF: Rate control

111

What are channels blocked, action potential phase and main uses in AF for class III anti-arrythmic drugs?

Channels blocked: K+
Action potential phase: 3
Main uses in AF: Rhythm control

112

What are channels blocked, action potential phase and main uses in AF for class IV anti-arrythmic drugs?

Channels blocked: Ca2+
Action potential phase: 2
Main uses in AF: rate control

113

Name 4 class I anti-arrythmic drugs?

1. Lignocaine
2. Quinidine
3. Flecainide
4. Propafenone

114

Give 1 class II anti-arrythmic drug?

Propranalol

115

Give three class III anti-arrythmic drugs?

1. Amiodarone
2. Sotalol
3. Dronedarone

116

Give one example of a class IV anti-arrythmic drug?

Verapamil

117

What is a rapid, distinct VT with a twisting configuration of the QRS morphology and associated with prolonged repolarisation?

Torsades de Pointes

118

What is the heart rate in Torsades de Pointes?

200 - 250bpm

119

What is the rhythm like in Torosades de Pointes?

Irregular

120

Give three features for ECG recognation of Torsades de Pointes?

1. Long QT interval
2. Wide QRS
3. Continuously changing QRS morphology

121

Give three events leading to TdP?

1. Hypokalaemia
2. Prolongation of the action potential duration (drug induced)
3. Renal impairment (increased drug levels)

122

What two valvular AF conditions would indicate for anti-coagulation?

Mitral stenosis
Mitral regurgitation

123

What does CHA(2)DS(2)-VAS Score stand for?

Congestive heart failure/LV dysfunction - 1
Hypertension - 1
Age>75 - 2
Diabetes mellitus - 1
Stroke (TIA/TE) - 2
Vascular disease - 1
Age 65-74 years - 1
Sex - 1

124

What does HASBLED assess?

Bleeding risk

125

What does HASBLED stand for? (>3 is high risk)

Hypertension
Abnormal renal or liver function
Stroke
Bleeding
Labile INRs
Elderly > 65
Drugs or alcohol

126

How does radiofrequency ablation in AF maintain SR?

By ablating AF focus (usually in the pulmonary veins)

127

How does radiofrequency ablation in AF control rate?

Ablation of the AVN to stop fast conduction to the ventricles

128

Name a rapid and regular form of atrial tachycardia?

Atrial flutter

129

What is atrial flutter (paroxysmal) sustained by?

Macro-reentrant circuit

130

Where is the atrial flutter circuit combined to?

Right atrium

131

What does chronic atrial flutter usually progress to?

AF

132

What is the rate usually in atrial flutter?

300bpm

133

What is seen instead of a p-wave in atrial flutter?

Saw tooth 'F' wave

134

Is atrial flutter clockwise or counterclockwise?

Counterclockwise

135

What are the four treatment options for atrial flutter?

1. RF ablation
2. Pharmacologic therapy - slow the ventricular rate, restore SR, maintain SR
3. Cardioversion
4. Warfarin for prevention of thromboembolism