Heart AV block

Question 1

Complete heart block

Answer 1

No relationship between p wave and QRS wave

Question 2

What is the management for complete heart block?

Answer 2

Pacemaker

Question 3

Stokes Adams Attacks

Answer 3

Associated with heart block and asystole

Episodes of loss of consciousness due to self-limiting tachyarrhythmias

Question 4

First degree heart block

Answer 4

Prolonged PR interval

Great than 20ms

Question 5

Second degree heart block

Type 1

Type 2

Answer 5

Type 1 - PR interval gets longer and longer until there is a dropped beat

Type 2 - PR interval is fixed but there are dropped beats at a certain frequency (e.g. 2 PR intervals to 1 beat / QRS interval)

Question 6

Heart block management

Answer 6

Same as bradycardia

Stable = observe

Unstable or risk of asystole (Mobitz Type 2 [ratio to dropped beat], complete heart block, prev Hx asystole):
1. Atropine

If no improvement:

• more atropine upto 6 doses
• inotropes e.g. noradrenalin
• transcutaneous pacing e.g. defribillator

If stable but risk of asystole:

• transvenous pacing (by specialist)
• permanent pacemaker

Question 7

Third degree heart block

Answer 7

complete heart block

no observable relationship between P waves and QRS complexes

significant risk of asystole with third degree heart block.