Wide-complex Tachycardia

Several algorithms exist for the electrocardigraphic evaluation of regular, wide-complex tachycardias with the objective of distinguishing ventricular tachycardia (VT) from a supraventricular tachycardia (SVT) with aberrant conduction. The algorithm detailed below, developed by Dr. James Niemann, presents an ED-centric approach favoring the diagnosis of the more life-threatening dysrhythmia. This approach recognizes that SVT with aberrancy is rare, particularly in patients with a history of cardiac disease where the likelihood of ventricular tachycardia exceeds 90%. The algorithm requires the use of only the most simple and easily-recalled criteria, and any point of failure along the algorithm lends to the universally-appropriate management as ventricular tachycardia.

Algorithm for the Evaluation of Regular, Wide-Complex Tachycardia

Algorithm for the Evaluation of Wide-Complex Tachycardia

  1. aVR: Is the initial deflection in aVR positive? If yes, then VT.
  2. Concordance: Is there concordance (monophasic with same polarity) in all of the precordial leads? If yes, then VT.
  3. AV Dissociation: Is there evidence of AV dissociation (fusion or capture beats)? If yes, then VT.
  4. Bundle-branch morphology: Is the QRS morphology in V1 and V6 consistent with either LBBB or RBBB? If no, then VT.

References

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  2. Vereckei A, Duray G, Szénási G, Altemose GT, Miller JM. New algorithm using only lead aVR for differential diagnosis of wide QRS complex tachycardia. Heart Rhythm. 2008;5(1):89-98. doi:10.1016/j.hrthm.2007.09.020.
  3. Szelényi Z, Duray G, Katona G, et al. Comparison of the “real-life” diagnostic value of two recently published electrocardiogram methods for the differential diagnosis of wide QRS complex tachycardias. Acad Emerg Med. 2013;20(11):1121-1130. doi:10.1111/acem.12247.
  4. Brugada P, Brugada J, Mont L, Smeets J, Andries EW. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex. Circulation. 1991;83(5):1649-1659.
  5. Lau EW, Pathamanathan RK, Ng GA, Cooper J, Skehan JD, Griffith MJ. The Bayesian approach improves the electrocardiographic diagnosis of broad complex tachycardia. Pacing Clin Electrophysiol. 2000;23(10 Pt 1):1519-1526.
  6. B Garner J, M Miller J. Wide Complex Tachycardia – Ventricular Tachycardia or Not Ventricular Tachycardia, That Remains the Question. Arrhythm Electrophysiol Rev. 2013;2(1):23-29. doi:10.15420/aer.2013.2.1.23.
  7. Vereckei A. Current algorithms for the diagnosis of wide QRS complex tachycardias. Curr Cardiol Rev. 2014;10(3):262-276.
  8. Garmel GM. Wide Complex Tachycardias: Understanding this Complex Condition: Part 1 – Epidemiology and Electrophysiology. West J Emerg Med. 2008;9(1):28-39.
  9. Garmel GM. Wide Complex Tachycardias: Understanding this Complex Condition Part 2 – Management, Miscellaneous Causes, and Pitfalls. West J Emerg Med. 2008;9(2):97-103.
  10. Griffith MJ, Garratt CJ, Mounsey P, Camm AJ. Ventricular tachycardia as default diagnosis in broad complex tachycardia. The Lancet. 1994;343(8894):386-388.