*** In Progress ***
Brandon Fainstad, MD
1. Characterize the electrophysiology of the eight supraventricular tachycardias.
2. Differentiate the supraventricular tachycardias based on regularity and ‘P’ wave morphology.
3. Identify the best step acute management for each rhythm.
Plan to spend at least 30 minutes preparing for this talk by using the Interactive Board for Learning/Preparing and clicking on each of the eight buttons to reveal the a graphic representation of the electrophysiology, ECG pattern and defining characteristics for each rhythm. After you feel comfortable with the content you can prepare to present this talk in one of two ways. 1. Project the Interactive Board for Presentation or 2. Reproduce the drawing on a whiteboard using the teacher’s handout as a guide.
With either method, print out enough copies of the Learner’s Handout and Practice ECGs so they can follow along during the presentation. Start by reviewing the objectives of the talk. Then introduce the concept that all forms of tachycardia result from either, 1. increased automaticity by a node or ectopic pacemaker, or 2. a re-entry circuit. In general, re-entry circuits are much faster. Secondly, that you could effectively determine the SVT rhythm based on regularity and the presence or morphology of P waves. Sometimes, this will require you to slow down the rate for better interrogation of the rhythm strip, or give adenosine to resolve the rhythm. After working through the eight rhythms have the audience practice by interpreting the Practice ECGs with the printouts or presentation. The entire talk will take 30-45 minutes to deliver.
INTERACTIVE BOARD FOR LEARNING/PREPARING
INTERACTIVE BOARD FOR PRESENTING
*See “Print outs” above for printable version
TAKE HOME POINTS
- Tachycardia is due to either increased automaticity of a pacemaker (nodal or ectopic) or a re-entry circuit. Re-entry circuits are generally faster.
- There are only 8 SVTs which are distinguished by regular vs. irregular rhythm and the presence or morphology of the p wave.
- Hemodynamically stable SVTs are acutely managed one of 3 ways:
- Address underlying disease (for sinus tach, atrial tach, junctional tach and multi-atrial tach)
- Resolve the re-entry circuit by interrupting AV conduction with vagal maneuvers or adenosine (for AVnRT and AVRT)
- Rate control with AV nodal blockers (for afib and aflutter)
Nelson, William Paul, Henry J. L. Marriott, and Douglas D. Schocken. Concepts and Cautions in Electrocardiography. Northglenn, CO: MedInfo Inc., 2007.