Ventricular tachycardia

Question 1

Define ventricular tachycardia

Answer 1

A regular broad-complex tachycardia originating from a ventricular ectopic focus. The rate is usually > 120 bpm.

Question 2

Explain the aetiology/risk factors of ventricular tachycardia

Answer 2

Electrical impulses arise from a ventricular ectopic focus

Risk Factors
Coronary heart disease

Structural heart disease

Electrolyte deficiencies (e.g. hypokalaemia, hypocalcaemia, hypomagnesaemia)

Use of stimulant drugs (e.g. caffeine, cocaine)

Question 3

Summarise the epidemiology of ventricular tachycardia

Answer 3

Fairly common

It is one of the shockable rhythms that is seen in cardiac arrest patients

VT incidence peaks in the middle decades of life

Question 4

Recognise the presenting symptoms of ventricular tachycardia

Answer 4

Symptoms of ischaemic heart disease or haemodynamic compromise due to poor perfusion

Symptoms:
Chest pain
Palpitations
Dyspnoea
Syncope

Question 5

Recognise the signs of ventricular tachycardia on physical examination

Answer 5

Signs are dependent on the degree of haemodynamic instability

Respiratory distress
Bibasal crackles
Raised JVP
Hypotension
Anxiety
Agitation
Lethargy
Coma

Question 6

Identify appropriate investigations for ventricular tachycardia

Answer 6

It can sometimes be difficult to distinguish between VT and SVT with aberrant conduction. If in doubt, treat as a VT

ECG Features:
Rate > 100 bpm
Broad QRS complexes
AV dissociation

Electrolytes - derangement can cause arrhythmias

Drug levels - e.g. check for digoxin toxicity

Cardiac enzymes - e.g. troponins to check for recent ischaemic event

Question 7

Generate a management plan for ventricular tachycardia

Answer 7

ABC approach - CHECK PATIENT FOR A PULSE

Pulseless VT - follow advanced life support algorithm
Unstable VT - reduced cardiac output

NOTE: VF and pulseless VT require defibrillation (unsynchronised), but other VTs can be treated with
synchronised cardioversion

Correct electrolyte abnormalities +Amiodarone

Stable VT - These patients DO NOT experience symptoms of haemodynamic compromise

Correct electrolyte abnormalities + Amiodarone

Synchronised DC shock (if steps above are unsuccessful)

Implantable Cardioverter Defibrillator (ICD)
ICD is considered if:
Sustained VT causing syncope
Sustained VT with ejection fraction < 35%
Previous cardiac arrest due to VT or VF
MI complicated by non-sustained VT

Question 8

Identify possible complications of ventricular tachycardia

Answer 8

Congestive cardiac failure
Cardiogenic shock
VT may deteriorate into VF

Question 9

Summarise the prognosis of ventricular tachycardia

Answer 9

GOOD if treated RAPIDLY

Long-term prognosis depends on the underlying cause