Junctional ectopic tachycardia (JET)
Also calledJET · junctional ectopic tachycardia · His bundle tachycardia
Definition
An automatic (nonreentrant) tachycardia arising from the AV junction, including the bundle of His (it has also been called His bundle tachycardia). The 2015 ACC/AHA/HRS SVT guideline notes that junctional tachycardia seen in infants after surgery for congenital heart disease is also known as junctional ectopic tachycardia and gives typical junctional tachycardia rates of 120 to 220 bpm; the rare congenital form in infants typically runs 200 to 250 bpm. The QRS is usually narrow and identical to a normally conducted beat. AV dissociation is common, with the junctional rate faster than the atrial rate, although retrograde conduction to the atria (in a Wenckebach pattern or, less often, 1:1) can occur. It characteristically speeds up gradually at onset ("warming up") and slows gradually at termination ("cooling down").
Clinical noteSeen mainly in infants and young children within the first 72 hours after surgery for congenital heart disease, and usually self-limited; a rarer congenital form also occurs.
Sources
- Kylat RI, Samson RA. Junctional ectopic tachycardia in infants and children. J Arrhythm. 2020;36(1):59-66. doi.org/10.1002/joa3.12282
- Page RL, Joglar JA, Caldwell MA, et al. 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia. Circulation. 2016;133(14):e506-e574. doi.org/10.1161/CIR.0000000000000311
Last reviewed 2 October 2026. Every definition in the EKG Dictionary cites the guideline, consensus statement or original paper it comes from.