Ventricular Arryhthmias

Question 1

Torsades de Pointes What is it? What does it look like on an ECG/

Answer 1

• Torsades is a polymorphic (multiple shape) ventricular tachycardia

ECG:

• normal ventricular tachycardia on an ECG however there is an appearance that the QRS complex is twisting around the baseline
• The height of the QRS complexes progressively get smaller, then larger then smaller and so on.
• It occurs in patients with a prolonged QT interval.
• irregular QRS complexes

Question 2

What are the causes of prolonged QT (and therefore potentially torsades)?

Answer 2

• Long QT Syndrome (inherited)
• Medications (antipsychotics, citalopram, flecainide, sotalol, amiodarone, macrolide antibiotics i.e. clarithromycin)
• Electrolyte Disturbance (hypokalaemia, hypomagnesaemia, hypocalcaemia)

Question 3

Torsades de Pointes

Acute management

Answer 3

Correct the cause (electrolyte disturbances or medications)

Magnesium infusion (even if they have a normal serum magnesium)

Defibrillation if VT occurs [Usually torsades are self limiting but if they progress to VT it can lead to a cardiac arrest so would need defibtillation]

Question 4

Long term management of prolonged QT syndrome

Answer 4

Avoid medications that prolong the QT interval

Correct electrolyte disturbances

Beta blockers (not sotalol)

Pacemaker or implantable defibrillator

Question 5

Ventricular Ectopics

What are they?

Clinical Features

ECG bigeminy

Management

Answer 5

Ventricular ectopics are premature ventricular beats caused by random electrical discharges from outside the atria

CLINICAL FEATURES:

• random, brief palpitations (“an abnormal beat”)
• more common in those with history of ischaemic heart disease or heart failure

BIGEMINY

• Bigeminy is where the ventricular ectopics are occurring so frequently that they happen after every sinus beat.
• ECG looks like a normal sinus beat followed immediately by an ectopic, then a normal beat, then ectopic and so on.

MANAGEMENT

• Check bloods for anaemia, electrolyte disturbance and thyroid abnormalities
• Reassurance and no treatment in otherwise healthy people
• Seek expert advice in patients with background heart conditions or other concerning features or findings (e.g. chest pain, syncope, murmur, family history of sudden death)

Question 6

Ventricular Fibrillation

Clinical Features

Answer 6

CLINICAL FEATURES

• Pulseless
• Shockable

Question 7

Ventricular Tachycardia

Clinical Feature

ECG feature

Management

Answer 7

CLINICAL:

• a canon waves on JVP

ECG:

• broad QRS complexes

MANAGEMENT:

• Amiodarone
• only cardioversion if pulseless

Question 8

What is this?

Answer 8

Ventricular fibrillation

Question 9

What is this?

Answer 9

Torsades de pointes

Question 10

What is this?

Answer 10

Bigeminy - where the ventricular ectopic beat happens so often it occurs after every sinus beat

Question 11

What is this?

Answer 11

Ventricular Tachycardia