Date Published

March 28, 2019

Updated For

ALS PCS Version ALS PCS Version 5.2


Do we HAVE to take a 12 lead to diagnose SVT?


YES. In order to differentiate tachycardia mechanism (via your diagnostic pathway taught in this years CME), you need to assess for Atrial activity (P-waves) in ALL leads. Therefore, a 12-lead ECG is required (2015 ACC/AHA/HRS Guidelines for Management of Adult Patients with Supraventricular Tachycardia)

Recall: Focused Approach to SVT (from Mandatory CME in-class) 1. Rate (HR 150 bpm) 2. QRS Normal (narrow vs wide) 3. Rhythm (Regular vs Irregular) 4. Atrial activity (P waves?) and relationship with QRS* 5. Normotensive 6. Unaltered

If yes, or the underline option, and Patient characteristics in keeping with your conclusion, you may consider the Valsalva Maneuver.

*With regards to Atrial activity and the diagnosis of SVT:

Signs of SVT include: Signs of non-SVT rhythm include:
  • cannot identify P-waves (buried in QRS)
  • retrograde P-waves (inverted)
  • P waves found after the QRS
  • upright P waves present before every QRS (sinus rhythm)
  • signs of impulse from sinus node: P wave upright in II, negative in aVR (sinus)
  • saw tooth P waves (consider Atrial Flutter)
  • fibrillating baseline (consider Atrial Fibrillation)

Page RL et al. 2015 ACC/AHA/HRS Guideline for the Management of Adult Patients With Supraventricular Tachycardia: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol. 2016. Apr 5;67(13):1575-1623.



Tachydysrhythmia, Valsalva

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