1: Broad Complex Tachyarrythmias

Question 1

What does broad complex tachycardia indicate

Answer 1

Arrhythmia has arisen from the ventricles

Question 2

What are the two types of ventricular tachycardia

Answer 2

Monomorphic + Polymorphic

Question 3

What is the most common type of VT

Answer 3

Monomorphic

Question 4

What causes monomorphic VT

Answer 4

MI

Question 5

What is a subtype of polymorphic VT

Answer 5

Torsades de pointes

Question 6

What causes torsades de pointes

Answer 6

Prolongation of the QT interval

Question 7

What is sustained VT

Answer 7

VT lasting more than 30s leading to haemodynamic compromise

Question 8

What is non sustained VT

Answer 8

3 or more consecutive ventricular complexes terminating spontaneously in 30s

Question 9

What causes monomorphic VT

Answer 9

MI or previous MI scars

Question 10

What causes polymorphic VT

Answer 10

Torsades de points (gradual prolongation of QT)

Question 11

What are the congenital causes of prolonged QT interval

Answer 11

Jervell-Lange Nielsen

Question 12

How does Jervell-Lange Nielsen present

Answer 12

With deafness

Question 13

How does Romano Ward present

Answer 13

Without deafness

Question 14

What drugs may prolong the QT interval

Answer 14

Macrolide antibiotics
TCA
Amiodarone
Sotolol 
Class I anti-arrythmics (procainmide) 
Chloroquinine
Terfenadine

Question 15

What are other causes of prolong QT

Answer 15

1. Hypocalcaemia
2. Hypokalaemia
3. Hypomagnesaemia
4. MI
5. Myocarditis
6. Hypothermia
7. Subarachnoid haemorrhage

Question 16

How will non-sustained VT present

Answer 16

Asymptomatic

Question 17

How will sustained VT present

Answer 17

Palpitations
Chest Pain
Hypotension
Shock 
Syncope

Question 18

What may sustained VT progress to

Answer 18

VF and death

Question 19

What are the 3 pathophysiolgocial mechanisms of VT

Answer 19

• Re-entry
• Triggered activity
• Automaticity

Question 20

What is the commonest mechanism underlying VT

Answer 20

Re-entry

Question 21

What is re-entry

Answer 21

Requires two distinct conduction pathways with a block in one and slowing in another

Question 22

What commonly causes re-entry

Answer 22

Scar from MI

Question 23

What is triggered activity

Answer 23

Where there are either early or late depolarisations

Question 24

What is abnormal automaticity

Answer 24

Region of ventricular cells causing abnormal conduction

Question 25

What is first line Ix for VT

Answer 25

ECG

Question 26

How will VT present on ECG

Answer 26

AV disassociation (no relationship between P wave and QRS)

Question 27

How will monomorphic VT present

Answer 27

QRS complexes appear the same

Question 28

How will polymorphic VT present

Answer 28

QRS complexes appear different

Question 29

How is haemodynamically unstable VT assessed

Answer 29

Whether a pulse is present or not

Question 30

How is haemodynamically unstable VT without pulse managed

Answer 30

Defibrillation

Question 31

How is haemodynamically unstable VT with pulse managed

Answer 31

DC cardioversion

Question 32

What is first-line for haemodynamically stable VT

Answer 32

Amiodarone

Question 33

How should Amiodarone be administered

Answer 33

Via a central line

Question 34

What is second line for Stable VT

Answer 34

Lidnocaine

Question 35

When should lidnocaine be used with caution

Answer 35

Individuals with severe left ventricular impairment

Question 36

What is 3rd line for VT

Answer 36

Procainmide

Question 37

What is used for long-term management of VT

Answer 37

Implantable cardiac defibrillator (ICD)

Question 38

How is torsades de pointes managed acutely

Answer 38

Magnesium sulphate

Question 39

How is torsades de pointes managed in the long-term

Answer 39

B blocker

Question 40

What is the main complication of VT

Answer 40

Can progress to VF and cause sudden cardiac death

Question 41

What is VF

Answer 41

A life-threatening cardiac arrhythmia characterised by high frequency ventricular contractions resulting in diminished cardiac output

Question 42

Explain the pathophysiology of VF

Answer 42

- when the ventricles are damaged there is tissue heterogeneity (cells have different electrical properties) - if ventricular pacemaker cells fire at the wrong time but a group of adjacent cells also fire this can cause a premature ventricular contraction - >3 PVC (VT) can lead to VF - If adjacent cells have different electrical properties it can lead to re-entry circuits

Question 43

How will ECG present in VF

Answer 43

No discernible P waves or QRS

Question 44

How is VF managed

Answer 44

Advanced Cardiac Life Support

Question 45

What is the main complication of VF

Answer 45

Sudden cardiac death