Contributor: Peter Bakes, MD
- Tachycardia describes a heart rate of >120 beats per minute
- Wide Complex describes a QRS duration of >120 ms or 3 small boxes on a standard EKG
- The major differential for a wide complex tachycardia is Ventricular Tachycardia (VT), aka “V Tach”, or Supraventricular Tachycardia (SVT) with Aberrancy
- SVT alone is a narrow complex tachycardia, but as rate increases a right or left bundle branch block pattern may emerge, creating SVT with Aberrancy seen as a wide complex on EKG
- It is important to distinguish the rhythms as treatment for stable VT differs from treatment(s) for stable SVT
- Brugada Criteria is an algorithm for determining if wide complex tachycardia is VT with a high degree of sensitivity and specificity.
- Following is a simple ED approach based on brugada criteria to determine VT on EKG. If either condition is true, suspect and treat VT:
- Concordance: All precordial leads have QRS complexes that are either all positive or all negative.
- R-S interval: >100 ms in any one precordial lead.
- Also note that VT is more common in patients who are elderly and/or have cardiac comorbidities of ischemic or structural heart disease
Reithmann C. Tachykardien mit breiten QRS-Komplexen [Differential diagnosis of wide QRS complex tachycardia]. MMW Fortschr Med. 2019;161(13):48-56. doi:10.1007/s15006-019-0022-x
Ding WY, Mahida S. Wide complex tachycardia: differentiating ventricular tachycardia from supraventricular tachycardia. Heart. 2021;107(24):1995-2003. doi:10.1136/heartjnl-2020-316874
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. doi:10.1161/01.cir.83.5.1649
Summarized by Kirsten Hughes, MS4 | Edited by John Spartz, MD & Erik Verzemnieks, MD
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