Arrythmias

Question 1

Where do supraventricular arrythmias originate?

Answer 1

Above the ventricle, e.g.: SA node, Atrial muscle, AV Node, the origin of the bundle of His.

Question 2

What does the Bachmann’s bundle supply?

Answer 2

Supplies electrical activity to the left atrium.

Question 3

What are ectopic beats?

Answer 3

Heart beats that originate outside the SA node

Question 4

Name as many supraventricular arrythmias as you can.

Answer 4

TACHY
Atrial fibrillation 
Atrial flutter
Ectopic atrial tachycardia
BRADY
Sinus bradycardia
Sinus pauses

Question 5

Name as many AV node arrythmias as you can.

Answer 5

AVN re-entyr
Accessory pathways - Wolff-Parkinson White
AV block - 1,2+3

Question 6

Name as many ventricular arrythmias as you can.

Answer 6

Premature ventricular complex (PVC)
Ventricular Tachycardia
Ventricular Fibrillation
Asystole

Question 7

What can cause arrythmias?

Answer 7

Congenital defects of the heart
Sympathetic stimulation and increased vagal tone
Hypoxia
Ischaemia
Electrolyte imbalance
Inflammation
Drugs
Genetics

Question 8

What is the basic cause of arrythmias?

Answer 8

A change in automaticity.

Question 9

Does hypothermia cause bradycardia or tachycardia?

Answer 9

Bradycardia

It decrease the phase 4 slope

Question 10

Does hyperthermia cause bradycardia or tachycardia?

Answer 10

Tachycardia

It increases the phase 4 slope

Question 11

Does hypercapnia cause bradycardia or tachycardia?

Answer 11

Tachycardia

It increases the phase 4 slope

Question 12

Does hypoxia cause bradycardia or tachycardia?

Answer 12

Tachycardia

It increases the phase 4 slope

Question 13

Does cardiac dilation cause bradycardia or tachycardia?`

Answer 13

Tachycardia

It increases the phase 4 slope

Question 14

Does hypokalaemia cause bradycardia or tachycardia?

Answer 14

Tachycardia
It increases the phase 4 slope
Also increases the presence of ectopics and prolongs repolarisation.

Question 15

Does hyperkalaemia cause bradycardia or tachycardia?

Answer 15

Bradycardia
It decrease the phase 4 slope
It slows conduction and blocks

Question 16

What does Digoxin toxicity cause?

Answer 16

Palpitations and irregular pulse. (Small depolarisation after phase 3)

Question 17

What are the symptoms of ischaemia and re-entry arrythmia?

Answer 17

Palpitations
Dizziness
Dyspnoea
Syncope
Sudden cardiac death
Worsening of current conditions

Question 18

Name the investigation for structural heart disease

Answer 18

Echocardiogram

Question 19

Name the investigation to assess rhythm, signs of previous MI and pre-excitation

Answer 19

ECG

Question 20

Name the investigation to assess ischaemia and exercise induced arrythmias.

Answer 20

Exercise ECG

Question 21

Name the investigation to assess for paroxysmal arrythmias

Answer 21

24hr Holter ECG

Question 22

What kind of symptoms would you see in atrial ectopic beats

Answer 22

Often none or palpitations

Question 23

How would you treat Atrial ectopic beats?

Answer 23

Generally no treatment
Avoids stimulants like caffeine and cigarettes
B blockers can help

Question 24

How would you treat bradycardia?

Answer 24

Atropine

Question 25

What is sinus bradycardia?

Answer 25

Heart rate

Question 26

What is sinus tachycardia?

Answer 26

Heart rate >100bpm

Question 27

How would you treat tachycardia?

Answer 27

Treat underlying pathology | B blockers

Question 28

What is the treatment for SVT (Supraventricular tachycardia)

Answer 28

Vagal manoeuvres e.g carotid massage IV Adenosine -A1 blocker IV Verapamil - Calcium Channel Blocker

Question 29

What is the chronic treatment for SVT?

Answer 29

Avoid stimulants | B blockers &/or Calcium channel blocker

Question 30

What is ablation?

Answer 30

Selective cautery of cardiac tissue to prevent tachycardia, targeting either an automatic focus or part of a re-entry circuit.

Question 31

Describe 1st degree heart block

Answer 31

Longer PR interval than normal (>0.2 sec) No treatment But long term follow up as it could get worse

Question 32

What is Mobitz I heart block?

Answer 32

2nd degree heart block Causes progressive lengthening of PR interval resulting in a dropped beat Usually vagal in origin

Question 33

What is Mobitz II heart block?

Answer 33

``` 2nd degree heart block Pathological May progress to complete heart block Its normally 2 beats to 1 dropped beat e.g 2:1 or can be 3:1 Permanent pacemaker needed ```

Question 34

Describe 3rd degree heart block

Answer 34

No action potential from the SAN get to through the AVN | Random P waves with no association to QRS

Question 35

List the options for acute pacing

Answer 35

Transcutaneous - Emergency until venous access is achieved. | Tranvenous pacer - Via main vein.

Question 36

What are the two types of pacemakers?

Answer 36

Single chamber - Used for arrythmias involving SAN | Dual chamber - Used for AVN disease

Question 37

How would you treat Premature ventricular ectopics?

Answer 37

B-Blockers | If they are worse on exercise you need to investigate further.

Question 38

What is a ventricular tachycardia caused by?

Answer 38

``` Life threatining condition caused by Coronary artery disease Previous MI Cardiomyopathy Inherited arrythmias ```

Question 39

What is ventricular fibrillation?

Answer 39

Chaotic ventricular electrical activity | Heart loses its ability as a pump`

Question 40

What is the treatment for VF?

Answer 40

Defib and resuscitation.

Question 41

What is the treatment for VT?

Answer 41

DC Cardioversion in acute unstable cases | If stable consider pharmacological cardioversion

Question 42

What is the long term treatment for VT?

Answer 42

Correct ischaemia ICD (Implantable cardioverter defibrillator) Optimise CHF therapies

Question 43

What can cause Torsades de Pointes

Answer 43

Digitalis toxicity