1. 1

2. In this podcast…
 Overview of tachycardic arrhythmias
 Look more in detail at the broad QRS
complex arrhythmias
 Causes
 Signs and symptoms
 What they look like on ECG
 Management

3. Overview
Tachycardiac
Arrhythmias
Broad QRS
Complex
Narrow QRS
Complex
ArrhythmiasArrhythmias

4. Broad QRS complex arrhythmias
Broad QRS
Complex
Ventricular
Ventricular
Tachycardia
Torsades de
pointes
Ventricular
Fibrillation
Supraventricular
tachycardia PLUS a
bundle branch block

5. Ventricular Tachycardia
Defined as three or more ventricular extrasystoles in
succession at a rate of >120bpm
 Causes
 Coronary heart disease- including acute MI
 Cardiomyopathies
 Signs and symptoms
 Can be pulseless- indicates minimal cardiac output
 Syncope
 Palpitations, chest pain
 Haemodynamic compromise

6. Ventricular Tachycardia
Distinguish VT from SVT with BBB--- very broad QRS (> 0.14 s)
Pulseless VT?
Immediate
defibrillation
Haemodynamically
compromised?
Urgent DC
Cardioversion
Stable?
Lignocaine or
amiodarone
Patient is…
2

7. Torsades de Pointes
Arises when ventricular repolarization (QT interval) is greatly
prolonged. Can degenerate into VF and cause death.
 Causes
 Congenital
 Acquired
 MI
 Drugs
 Bradycardia
 Electrolyte disturbances
 Signs and symptoms
 Palpitations, dizziness and syncope.
 Often terminates spontaneously
Remember
‘all the hypos’
Antiarrhythmic drugs (Sotalol, Amiodarone)
Erthromycin
Amitriptyline

8. Torsades de Pointes
QRS amplitude varies and the QRS complexes appear to twist around the baseline
 Management
 Correct electrolyte imbalances
 Stop causative drugs
 IV magnesium (even if magnesium levels are normal)
 Be aware that defibrillation may be needed if VF
occurs.
3

9. Ventricular Fibrillation
Produces rapid, ineffective, uncoordinated movement of the
ventricles, which therefore produce no pulse and no cardiac
output.
 Causes
 MI/ischaemia
 Structural heart disease
 Long QT syndrome (Torsades de Pointes)
 Signs and symptoms
 Patient will likely be unconscious and pulseless

10. Ventricular Fibrillation
Defibrillation and
resuscitation!
4

11. Supraventricular tachycardia
with bundle branch block
Causes, symptoms and management are similar to SVT
without BBB
i.e. Treatment with adenosine

12. Summary
 Broad QRS complex tachycardic arrhythmias.
 Most are ventricular in origin with the exception
of SVT with BBB.
 Ventricular tachycardia
 Assess patient; shockable if pulseless. May
need DC cardioversion or lidocaine or
amiodarone
 Torsades de Pointes
 Remove causes first, then magnesium is
treatment of choice
 Ventricular fibrillation
 shockable!

13. Thank you for listening!
References
1. Creative Commons Attribution-NonCommercial-ShareAlike 2.0 License. Author; www.soil-net.com (accessed
12th March 2011). Image altered by Charlotte Clifford
2. Creative commons Attribution-Share Alike 3.0 Unported License. Author; Glenlarson (accessed 12th March 2011)
3. Creative commons Attribution-Share Alike 3.0 Unported License. Author; displaced (accessed 12th March 2011)
4. Creative commons Attribution-Share Alike 3.0 Unported License. Author; Andersat (accessed 12th March
2011)Image altered by Charlotte Clifford