Arrhythmias

Question 1

What are arrhythmias?

Answer 1

Abnormalities in the cardiac rhythm generated by abnormal electrical conduction, usually by ectopic beats

Question 2

What are ectopic beats?

Answer 2

Beats that originate in places other than the SA node

Question 3

What is re-entry?

Answer 3

Where there is more than one conduction pathway, with different speeds of conduction

Question 4

What are the types of supra-ventricular arrhythmia?

Answer 4

Tachycardia:

• Atrial fibrillation
• Atrial flutter
• Ectopic atrial tachycardia

Bradycardia:

• Sinus bradycardia
• Sinus pauses

Question 5

Where do supra ventricular arrhythmias originate?

Answer 5

Within or above the AV node

Question 6

What is sinus arrhythmia?

Answer 6

Where the heart is in sinus rhythm but the heart rate is irregular

Question 7

What are the types of ventricular arrhythmia?

Answer 7

Ventricular ectopic
Ventricular tachycardia
Ventricular fibrillation
Asystole

Question 8

Are supraventricular and ventricular arrhythmias narrow or broad complex?

Answer 8

Supraventricular - narrow complex

Ventricular - broad complex

Question 9

What are the types of AV node arrhythmia?

Answer 9

AV re-entry tachycardia
AV block (1st, 2nd or 3rd degree)

Question 10

What are the causes of arrhythmia?

Answer 10

Abnormal anatomy
Autonomic nervous system
Metabolic
Inflammation (viral myocarditis)
Drugs
Genetic

Question 11

What are the ways in which abnormal anatomy can cause arrhythmia?

Answer 11

LV hypertrophy
Accessory pathways
Congenital heart defect

Question 12

What are the ways in which the autonomic nervous system can cause arrhythmia?

Answer 12

Sympathetic stimulation: stress, exercise, hyperthyroidism

Increased vagal tone causing bradycardia

Question 13

What are the metabolic causes of arrhythmia?

Answer 13

Hypoxia (chronic pulmonary disease, pulmonary embolism)
Ischaemic myocardium (acute MI, angina)
Electrolyte imbalances (K+, Ca2+, Mg2+)

Question 14

In what way can genetics cause arrhythmia?

Answer 14

Mutation of genes encoding cardiac ion channels, e.g. congenital long QT syndrome

Question 15

What is atrial fibrillation?

Answer 15

Disorganised electrical activity, resulting in irregular ventricular response

Question 16

What are the symptoms of atrial fibrillation?

Answer 16

Palpitations

Question 17

What are the three types of atrial fibrillation, and how are they classed?

Answer 17

Paroxysmal - <48 hours
Persistent - >48 hours
Permanent - unable to return to normal sinus rhythm

Question 18

What does an ECG show in atrial fibrillation?

Answer 18

No P waves
Irregularly irregular
Isoelectric line deviation
Ventricular rate 30-200bpm

Question 19

What is the treatment to control rate in atrial fibrillation?

Answer 19

Combination of digoxin and a beta blocker/verapamil

AV node ablation

Question 20

What is the treatment to control rhythm in atrial fibrillation?

Answer 20

Class I (disopyramide) or III (amiodarone)
DCCV

Question 21

When should you anti-coagulate in atrial fibrillation?

Answer 21

If prosthetic valves or CHADVAS score >2

Question 22

What is atrial flutter?

Answer 22

Atrial re-entry tachycardia, leading to rapid atrial rate.

Not all P-waves make it to the ventricles, so atria ‘flutter’

Question 23

What are the symptoms of atrial flutter?

Answer 23

Palpitations

Question 24

What does an ECG show in atrial flutter?

Answer 24

Sawtooth pattern
Multiple P waves before a QRS
Ventricular rate of approx 300bpm

Question 25

What is the treatment for atrial flutter?

Answer 25

Electrical cardioversion Radiofrequency ablation Class III drugs (amiodarone)

Question 26

What is Wolf-Parkinson White syndrome?

Answer 26

Atrial re-entry tachycardia with accessory excitatory pathway through the Bundle of Kent

Question 27

What are the symptoms of Wolf-Parkinson White syndrome?

Answer 27

Palpitations | Tachycardia

Question 28

What does an ECG show in Wolf-Parkinson White syndrome?

Answer 28

``` Short PR interval Sloping QRS (delta wave) ```

Question 29

What is the treatment for Wolf-Parkinson White syndrome?

Answer 29

DCCV Beta blockers, calcium channel blockers Catheter ablation

Question 30

What are the symptoms of ventricular tachycardia?

Answer 30

``` Dizziness Hypotension Palpitations Cardiac arrest Patients usually have other heart conditions ```

Question 31

What does an ECG show in ventricular tachycardia?

Answer 31

Wide complexes Polymorphisms (torsade de pointes) Mountains

Question 32

What is the treatment for unstable ventricular tachycardia?

Answer 32

DCCV

Question 33

What is the treatment for pulseless ventricular tachycardia?

Answer 33

Defibrillation

Question 34

What is the treatment for stable ventricular tachycardia?

Answer 34

Amiodarone + class I (lignocaine)

Question 35

What is ventricular fibrillation?

Answer 35

Rapid irregular conduction with useless effect | Life threatening, cardiac arrest often follows

Question 36

What are the symptoms of ventricular fibrillation?

Answer 36

Syncope | Cardiac arrest

Question 37

What re the signs of ventricular fibrillation on ECG?

Answer 37

Wandering baseline Irregular Random waveforms No identifiable QRS

Question 38

What is the treatment for ventricular fibrillation?

Answer 38

Defibrillation Magnesium chloride Implantable cardioverter defibrillator if long term

Question 39

What is 1st degree heart block?

Answer 39

PR interval longer than normal (>2 seconds) | Does not require treatment, just long term follow up

Question 40

What is 2nd degree heart block, Mobitz I?

Answer 40

Progressive lengthening of the PR interval, eventually resulting in a dropped beat

Question 41

What is 2nd degree heart block, Mobitz II?

Answer 41

Some missing P waves

Question 42

What is 3rd degree heart block (complete heart block)?

Answer 42

No action potentials from the SA node/atria get through, no connection between P wave and QRS

Question 43

What is there a risk of in a trial fibrillation?

Answer 43

Embolic stroke

Question 44

What are the signs of ectopic atrial tachycardia on ECG?

Answer 44

Varying PR and RR interval, some beats come early

Question 45

Which heart rhythms are shockable?

Answer 45

Ventricular tachycardia or fibrillation

Question 46

Which heart rhythms would you do CPR on?

Answer 46

Pulseless electrical activity Asystole Complete AV block