Arrhythmias

Question 1

What are the shockable rhythms?

Answer 1

Ventricular tachycardia

Ventricular fibrilation

Question 2

What are the non-shockable rhythms?

Answer 2

Pulseless electrical activity

Asystole

Question 3

Describe pulseless electrical activity

Answer 3

all electrical activity except VF/VT, including sinus rhythm with no pulse

Question 4

What is the treatment of tachycardia in an unstable patient?

Answer 4

Consider up to 3 synchronised shocks

Consider Amiodarone infusion

Question 5

Describe tachycardia treatment in stable patient with narrow complex tachycardia

Answer 5

AF- rate control with BB or diltiazem
Atrial flutter- control rate with BB
Supraventricular - treat with vagal manoeuvres and adenosine

Question 6

Describe tachycardia treatment in stable patient with wide complex tachycardia

Answer 6

Ventricular - amiodarone infusion

if know SVT with BBB - treat as normal SVT

If irregular may be AF variation -seek expert help

Question 7

How does atrial flutter appear on an ECG?

Answer 7

150bpm ventricular contraction

sawtooth appearance on ECG with P wave after p wave

Question 8

What conditions are associated with atrial flutter?

Answer 8

hypertension
Ischaemic heart disease
cardiomyopathy
thyrotoxicosis

Question 9

What is the treatment of Atrial flutter?

Answer 9

Rate/ rhythm control
treat reversible underlying condition
radio frequency ablation
anticoagulation based of Chad2ds2vasc score

Question 10

What causes supraventricular tachycardia?

Answer 10

the electrical signal re-entering the atria from the ventricles.

Question 11

How does SVT appear on an ECG?

Answer 11

Narrow complex tachycardia. It looks like a QRS complex followed immediately by a T wave, QRS complex, T wave and so on

Question 12

What are the 3 main types of SVT?

Answer 12

Atrioventricular nodal re-entrant tachycardia

Atrioventricular re-entrant tachycardia

Atrial tachycardia

Question 13

Describe the acute management of stable patients with SVT

Answer 13

Continuous ECG monitoring
Valsalva manoeuvre
Carotid sinus massage
Adenosine
verapamil
direct current cardioversiom

Question 14

What leads to Wolff-Parkinson White syndrome?

Answer 14

An extra electrical pathway connecting the atria and the ventricles.

Question 15

What are the ECG changes in WPW syndrome?

Answer 15

Short PR (<0.12 seconds)
Wide QRS complex (>0.12)
"delta wave" which is a stirred upstroke on the QRS complex

Question 16

Describe Torsades de Pointes

Answer 16

a polymorphic ventricular tachycardia. It looks like normal VT but there is an appearance of the QRS twisting around the baseline. The height of the QRS complexes progressively get smaller.
Occurs in patients with a prolonged QT interval

Question 17

What are the causes of prolonged QT?

Answer 17

Long QT syndrome (inherited)
Medications (antipsychotics. citalopram, flecainide, sotalol, amiodarone, macrolide antibiotics)
Electrolyte disturbances (hypokalaemia, hypomagnesaemia, hypocalcaemia

Question 18

What is the acute management of torsades de pointes?

Answer 18

Correct the cause
MAgnesium infusion
Defibrilation if VT occurs

Question 19

what is the long term management of prolonged QT syndrome?

Answer 19

Avoid QT prolonging meds
Correct electrolyte disturbances 
beta blockers (not sotalol)
Pacemakers or implantable defib

Question 20

What are ventricular ectopics?

Answer 20

Premature ventricular beats caused by random electrical discharges from outside the atria

Question 21

What is the management of ventricular ectopics?

Answer 21

Check bloods for anaemia, electrolyte disturbance and thyroid abnormalities

Reassurance in the healthy

seek advice for patients with heart disease

Question 22

Describe first degree heart block

Answer 22

Occurs when there is delayed AV conduction. Despite this, every atrial impulse leads to a ventricular contraction meaning every p wave leads to a QRS complex

Question 23

How does first degree heart block present on an ECG?

Answer 23

PR >0.2 seconds

Question 24

Describe second degree heart block

Answer 24

where some of the atrial impulses do not make it though the AV node to the ventricles. This means there are instances when the p waves do not lead to QRS complexes

Question 25

Describe mobitz type 1

Answer 25

The atrial impulses become gradually weaker until it no longer conducts to the ventricles.

Question 26

How does mobitz type 1 present on an ECG?

Answer 26

increasing PR interval until the p wave no longer conducts to the ventricles. The cycle repeats

Question 27

Describe mobitz type 2

Answer 27

Intermitted failure or interruption of SV conduction. This results in missing QRS complexes. Usually a set ratio of P waves to QRS complexes. The PR intervall remains normal. There is a risk of asystole

Question 28

Describe third degree heart block

Answer 28

complete heart blokc

NO observable relationship between p waves and QRS complexes. There is a significant risk of asystole

Question 29

How should stable bradycardia be managed?

Answer 29

observation

Question 30

How should unstable or mobitz type 2 / type 3 heart block be treated?

Answer 30

Atropine 500mcgIV

then up to 6 doses of atropine
Other inotropes such as noradrenalin
Transcutaneous cardiac pacing

Question 31

What options are available to patients with a high risk of asystole?

Answer 31

Temporaty transvenous cardiac pacing

permanent implantable pacemaker

Question 32

what are the side effects of atropine

Answer 32

Inhibits parasympathetic system

pupil dilatation, urinary retention, dry eyes and constipation