Contributor: Travis Barlock, MD

Educational Pearls:

• SVT: supraventricular tachycardia

• Pharmacotherapy for SVT includes drugs that block the AV node, such as adenosine

• EKG criteria before adenosine administration in SVT

1. Regular rhythm

2. Monomorphic: ​​all QRS complexes are identical

• If the EKG is polymorphic, with QRS complexes displaying changing morphologies, it is unsafe to administer adenosine 

• Adenosine can worsen polymorphic VTach and lead to VFib

References

1. Ganz, Leonard I., and Peter L. Friedman. “Supraventricular Tachycardia.” New England Journal of Medicine, vol. 332, no. 3, 19 Jan. 1995, pp. 162–173, https://doi.org/10.1056/nejm199501193320307.

2. Smith JR, Goldberger JJ, Kadish AH. Adenosine induced polymorphic ventricular tachycardia in adults without structural heart disease. Pacing Clin Electrophysiol. 1997;20(3 Pt 1):743-745. doi:10.1111/j.1540-8159.1997.tb03897.x

3. Viskin, Sami, et al. “Polymorphic Ventricular Tachycardia: Terminology, Mechanism, Diagnosis, and Emergency Therapy.” Circulation, vol. 144, no. 10, 7 Sept. 2021, pp. 823–839, https://doi.org/10.1161/circulationaha.121.055783.

Summarized by Meg Joyce, MS1 | Edited by Meg Joyce & Jorge Chalit, OMS3

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