Differential Diagnosis of Wide Complex Tachycardia

1. Wide Complex
Tachycardia
AHMED AMMAR, MSC, MD
EP FELLOW
EAST SUSSEX NHS TRUST

2. Differential Diagnosis of Wide–QRS Complex
Tachycardia
 Ventricular tachycardia
 SVT with pre-existing bundle-branch block or intraventricular conduction
defect
 SVT with aberrant conduction due to tachycardia (normal QRS when in sinus
rhythm)
 SVT with wide QRS related to electrolyte or metabolic disorder
 SVT with conduction over an accessory pathway (pre-excitation)
 Paced rhythm
 Artifact

3.  When doubt exists, it is safest to
assume any wide complex
tachycardia is VT, particularly in
patients with known cardiovascular
disease, such as prior myocardial
infarction.

4. First Step
History Taking and Examination

5. The likelihood of VT is increased with:
 Age > 35 (positive predictive value of 85%)
 Structural heart disease
 Ischaemic heart disease
 Previous MI
 Congestive heart failure
 Cardiomyopathy
 Family history of sudden cardiac death (suggesting conditions such as HOCM,
congenital long QT syndrome, Brugada syndrome or arrhythmogenic right
ventricular dysplasia that are associated with episodes of VT)

6. The likelihood of SVT with aberrancy is increased if:
 Previous ECGs show a bundle branch block pattern with identical
morphology to the broad complex tachycardia.
 Previous ECGs show evidence of WPW (short PR < 120ms, broad
QRS, delta wave).
 The patient has a history of paroxysmal tachycardias that have
been successfully terminated with adenosine or vagal manoeuvres.

7. Second Step

8. ECG Criteria to Differentiate VT From SVT in Wide-Complex
Tachycardia

9. Brugada Criteria

15. RBBB

16. VT

17. VT

18. SVT

19. LBBB

20. VT

21. Any Q wave
VT

22. Verecki Algorithim

24. Other ECG findings

25. Capture and Fusion Beats

26. Brugada’s sign and Josephson’s sign

27. R Wave Peak Time

30. AVNRT with LBBB

32. VT

34. Sinus
tachycardia

36. Pre-excited
AF

38. Antidromic
AVRT

40. Rapid ventricular paced
rhythm (e.g. pacemaker-
mediated tachycardia)

42. Artefact

43.  When doubt exists, it is safest to
assume any wide complex
tachycardia is VT, particularly in
patients with known cardiovascular
disease, such as prior myocardial
infarction.

44. Questions?