Arrhythmias

Question 1

What are the 2 shockable rhythms?

Answer 1

VF

VT

Question 2

What are causes of narrow complex tachycardia?

Answer 2

AF
Atrial flutter
Supraventricular tachycardias

Question 3

How do you treat AF?

Answer 3

Rate control with BB or diltiazem

Question 4

How do you manage atrial flutter?

Answer 4

Control rate with BB or cardioversion
Radiofrequency ablation of reentrant rhythm
Antocoag based on CHA2DS2VASC

Question 5

How do you manage supraventricular tachycardias in stable patients?

Answer 5

1. Vagal manouvres (blow hard against resistance)
2. Carotid sinus massage
3. Adenosine or Verapimil
4. Direct current cardioversion
   Monitor ECG throughout

Question 6

How do you manage VT

Answer 6

Amiodarone infusion through central line
Lidocaine with caution if severe
Procainamide
If adverse( (low BP etc) cardioversion if drugs fail (impanted cardioverter)

Question 7

What causes broad complex tachycardias?

Answer 7

VT

SVT with BBB

Question 8

WHat causes atrial flutter?

Answer 8

Re-entrant rhythms in the atria

Question 9

WHat speed is the atria stimulated at in atrial flutter?

Answer 9

300 bpm

Question 10

What conditions is atrial flutter associated with?

Answer 10

HTN
Ischaemic heart disease
Cardiomyopathy
Thyrotoxicosis

Question 11

What causes SVT?

Answer 11

Re-entrant circuits to the atria from the ventricles.

Question 12

What does SVT look like on ECG?

Answer 12

QRS with T immediately after, then QRS again

Question 13

What are the 3 kinds of SVT?

Answer 13

Atrioventricular nodal re-entrant (re-enters through AV node)
Atrioventricular re-entrant tachycardia- accessory pathway (WPW)
Atrial tachycardia- originally comes from somewhere other than SAN. Causes atrial rate of >100

Question 14

How does adenosine work?

Answer 14

Slows cardiac condution through AV node, interrupting circuit and restting to sinus rhythm. Must be given as rapid bolus

Question 15

When should adenosine be avoided?

Answer 15

Asthma
COPD
heart failure
HEart block
Hypotension

Question 16

How is adenosine given?

Answer 16

Rapid bolus into antecubital fossa
6 then 12 then 12mg
Patient will feel like going to die
Asystole or Brady period

Question 17

How is chronic/recurrent SVT managed?

Answer 17

BB CCB

Radiofrequency ablation

Question 18

What is WPW?

Answer 18

An extra electrical pathway connecting atria and ventricles

Question 19

What is management of WPW?

Answer 19

Radiofrequency ablation

Question 20

What are ECG changes in WPW?

Answer 20

Short PR
Wide QRS
Delta wave

Question 21

What is contraindicated in WPW and why

Answer 21

BB
CCB
Adenosine
Reduce conduction through AV node making issue worse

Question 22

Radiofrequency ablation is curative for which arrythmias?

Answer 22

AF
Atrual flutter
SVT
WPW

Question 23

What is Torsades de pointes?

Answer 23

Polymorphic (multiple shape) VT. QRS appears to twist around baseline, height getting smaller then larger. Long QT. Caused by abnormal repolatisation (therefore caused by long QT)

Question 24

HOw do you manage Torsades de Pointes?

Answer 24

Self limiting
Acute- Mg infusion
Defibrillation if VT occurs

Question 25

What causes long QT?

Answer 25

Long QT inherited syndrome (Romano Ward) Emotion or excercise Antipsychotics Citalopram Sotalol, Flecainide, Amiodarone, Macrolides Hypokalaemia, Hypomagnseium, Hypocalcaemia

Question 26

What is long term management of Long QT?

Answer 26

Avoid causative agents Correct electrolyte disturbance BB (not sotalol) Pacemaker/Defibrillator implanted

Question 27

What are ventricular ectopics?

Answer 27

Random beats from random electrical discharges outside atria | Common

Question 28

What do ventricular ectopics look like on ECG?

Answer 28

Random broad QRS on otherwise normal ECG

Question 29

What are begemini ectopics?

Answer 29

So many ventricular ectopics that there are 2 QRS for each P

Question 30

How do you manage ventricular ectopics?

Answer 30

Reassurance Check for electrolyte imbalance and anaemia No treatment needed

Question 31

What is first degree heart block? (AVN)

Answer 31

Delayed conduction through AVN but still 1 QRS per P | Looks like long PR interval (1 big square, 5 small)

Question 32

What is second degree heart block?

Answer 32

Some atrial impulses dont make it through AVN- several patterns

Question 33

What is Mobitz type 1 block (Wenckebach's phenomenon)

Answer 33

Atrial pulses get weaker and weaker until one doesnt pass through AVN, then goes back to being strong On ECG increasing PR until P no longer conducts and QRS dropped, the restarts

Question 34

What is Mobitz type 2?

Answer 34

Intermittant failure of AVN so missing QRS, usually in a set ratio of p to qrs, ie 3:1 PR interval stays normal Risk of asystole

Question 35

What is 3rd degree heart block?

Answer 35

Complete No relationship between P and QRS Big risk of asystole

Question 36

How do you manage stable bradycardia/AVN?

Answer 36

Observe

Question 37

How do you manage type 2 mobitz or complete heart block?

Answer 37

Atropine 500mcg IV Then repeat if no improvement up to 6 times Then Noradrenaline Then Defibrillator/ transcuatenous pacing wire before permanent pacemaker

Question 38

What side effects does atropine cause?

Answer 38

Pupil dilation Urine retention Dry eyes Constipation

Question 39

What causes RBBB?

Answer 39

``` TOF ASD PE PH MI RVH ```

Question 40

What causes LBBB?

Answer 40

Aortic stenosis MI HTN

Question 41

How is long QT managed?

Answer 41

BBs

Question 42

What should NOT be used in VT?

Answer 42

Verapimil