QuestionSBA
QuestionChoice
This is not a normal ECG. There are no discernible P waves and the QRS complexes are very broad
33522
e
Normal ECG
QuestionChoice
This a typical ECG showing monomorphic ventricular tachycardia. This is characterised by regular, wide QRS complexes of equal amplitude (monomorphic) with an absence of P waves. This patient is conscious (and would have a pulse if felt for) so they are not in cardiac arrest, however they do require urgent management. This patient would need urgent escalation to a senior colleague, with consideration for agents such as amiodarone to cardiovert them back to normal rhythm
33518
a
Ventricular tachycardia
QuestionChoice
This ECG does not show atrial fibrillation. Atrial fibrillation is characterised by an irregularly irregular rhythm and absent P waves. Although this ECG does not have P waves, the rhythm is regular. This is also a broad complex tachycardia, whereas atrial fibrillation presents with narrow complexes
33519
b
Atrial fibrillation
QuestionChoice
Torsades de pointes is also known as polymorphic ventricular tachycardia. Monomorphic and polymorphic ventricular tachycardia are both broad complex tachycardias with a regular rhythm. However, polymorphic ventricular tachycardia has QRS complexes of varying amplitude, whereas monomorphic ventricular tachycardia has QRS complexes with no significant difference in amplitude (as shown in this question)
33520
c
Torsades de pointes
QuestionChoice
Cardiac tamponade can occur after myocardial infarction, and is associated with rupture of the ventricular wall. However this question does not mention the characteristic features of Beck's triad (muffled heart sounds, hypotension, raised jugular venous pressure (JVP)) and this ECG does not show electrical alternans (the amplitude of the QRS complexes swapping between beats)
33521
d
Cardiac tamponade
Concept
Chapter
# Summary 

Broad complex tachycardia refers to dysrhythmias with a heart rate greater than 100 beats per minute and a QRS complex broader than 120 milliseconds. This term encompasses life-threatening rhythms such as ventricular tachycardia (VT) and ventricular fibrillation (VF). VT is a regular, broad complex tachycardia and may be with or without a pulse. In contrast, VF is irregular and is always pulseless. Pulseless VT and VF must be managed according to the ALS algorithm and require immediate defibrillation and administration of medications like adrenaline and amiodarone, whilst managing pulsed VT involves synchronised shocks and amiodarone. SVT with aberrancy, a condition where supraventricular tachycardia occurs in the presence of bundle-branch block, can mimic VT and should be treated cautiously.

# Definition 

Broad complex tachycardias are dysrhythmias that have a heart rate greater than 100bpm and a QRS complex that is greater than 120ms. The most common broad complex tachycardias are ventricular tachycardia or ventricular fibrillation. 

# Ventricular Tachycardia (VT)

A regular broad complex tachycardia. It can occur with a pulse or it may be pulseless. 

ECG features include: 

* Tachycardia (>100 beats per minute)
* Absent p waves
* Monomorphic regular broad QRS complexes (>120ms)

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# Management of VT 

## Pulseless VT 

If there is no pulse the patient should be managed according to the Advanced Life Support algorithm. 

* Pulseless VT is a shockable rhythm so a 200J bi-phasic **unsynchronised** shock should be administered. 
* IV adrenaline (1mg of 10ml 1:10,000 solution) and IV amiodarone (300mg) should be administered after delivery of the 3rd shock.
* Adrenaline should be administered every 3-5 minutes thereafter.  

## Pulsed VT with Adverse Features

If the patient has a pulse but is demonstrating adverse features (shock, syncope, myocardial ischaemia, or heart failure) the patient should be managed according to Resuscitation Council Tachyarrhythmia algorithm. 

* Administer synchronised DC shocks (up to 3 attempts). If the patient is conscious this will require sedation or anaesthesia. 
* Expert help should guide amiodarone administration (300mg IV over 10-20 minutes followed by 900mg infusion over 24 hours). 

## Pulsed VT with No Adverse Features 

If the patient has a pulse and is not demonstrating adverse features then the Resuscitation Council Tachyarrhythmia algorithm should be followed. 

* Amiodarone 300mg IV over 10-60 minutes. 
* If this is ineffective then administer synchronised DC shocks (up to 3 attempts). If the patient is conscious this will require sedation or anaesthesia. 
* *N.B. if there has been a previous certain diagnosis of SVT with aberrancy treat as for regular narrow complex tachycardias*

# Ventricular fibrillation (VF) 

An irregular broad complex tachycardia. This is always a pulseless rhythm.

ECG features include: 

* Tachycardia >100bpm 
* QRS complexes are polymorphic and irregular (>120ms)

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# Management of VF

The patient should be managed according to the Advanced Life Support algorithm. 

* VF is a shockable rhythm so a 200J bi-phasice **unsynchronised** shock should be administered. 
* IV adrenaline (1mg of 10ml 1:10,000 solution) and IV amiodarone (300mg) should be administered after delivery of the 3rd shock.
* Adrenaline should be administered every 3-5 minutes thereafter.

# Other Broad Complex Tachycardias 

Include: 

* Torsades des pointes: see section. 
* SVT with aberrancy: occurs when a patient with a bundle-branch block goes into SVT. It can be difficult to distinguish between VT and an SVT with aberrancy. The safest approach is to treat as VT. 

[lightgallery2]

# NICE Guidelines

[NICE CKS Guidelines for Cardiac Arrest and ALS](<https://cks.nice.org.uk/topics/cardiac-arrest-out-of-hospital-care/management/advanced-life-support-adult/>)

# References
[Resuscitation Council UK Adult Tachycardia Algorithm](<https://www.resus.org.uk/sites/default/files/2021-04/Tachycardia%20Algorithm%202021.pdf>)

[Resuscitation Council UK Adult ALS Algorithm](<https://www.resus.org.uk/sites/default/files/2021-04/Adult%20Advanced%20Life%20Support%20Algorithm%202021.pdf>)
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ECG Interpretation
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Cardiology
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Torsade de pointes on an ECG.
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Broad Complex Tachycardia
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ECG Interpretation
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Cardiology
A 67 year old patient is on the cardiology ward following a myocardial infarction. They received percutaneous coronary intervention six hours ago. They now feels breathless and dizzy, and their current ECG trace is shown below:

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What is the most likely diagnosis?
a