Junctional tachycardia: Difference between revisions
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**AV node | **AV node | ||
**Bundle of His | **Bundle of His | ||
*Also referred to as Junctional Ectopic Tachycardia | *Also referred to as Junctional Ectopic Tachycardia (JET) or Congenital Ectopic Tachycardia (CJET) if present at birth | ||
* Rate exceeds the upper limit seen in normal sinus rhythm | * Rate exceeds the upper limit seen in normal sinus rhythm | ||
**In adults, >100 bpm | **In adults, >100 bpm | ||
**In pediatric patients it varies by age until age 8 or 9 (see [[Pediatric vital signs|pediatric vital signs]]) | **In pediatric patients it varies by age until age 8 or 9 (see [[Pediatric vital signs|pediatric vital signs]]) | ||
===Junction Rhythm Classification=== | |||
''Arbitrarily classified by rate'' | |||
*[[Junctional escape rhythm]]: 40-60 bpm | |||
*[[Accelerated junctional rhythm]]: 60-100 bpm | |||
*[[Junctional tachycardia]]: >100 bpm | |||
==Clinical Features== | ==Clinical Features== | ||
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==Differential Diagnosis== | ==Differential Diagnosis== | ||
{{Tachycardia (narrow) DDX}} | {{Tachycardia (narrow) DDX}} | ||
{{Tachycardia (wide) DDX}} | |||
==Evaluation== | ==Evaluation== | ||
[[File:Junctional Tachycardia.jpg|thumb|ECG showing junctional tachycardia. Note narrow complex QRS, no P waves, and accelerated rate.]] | |||
*[[ECG]] findings | *[[ECG]] findings | ||
**P waves | **P waves | ||
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**QRS complexes | **QRS complexes | ||
***Narrow in the absence of aberrancy | ***Narrow in the absence of aberrancy | ||
*May be distinguished from AVNRT via Adenosine administration | |||
**''If JET is present'', atrial depolarization will briefly terminate and reveal AV dissociation | |||
**''If AVNRT is present'', conversion to sinus rhythm will likely occur | |||
**Avoid administration in the setting of aberrancy | |||
**JET will concomitant 3 degree AVB is rare | |||
*Consider JET underlying causes to include | |||
**Electrolyte abnormalities | |||
**Acidosis | |||
**Cardiovascular surgery within 24-48 hrs | |||
==Management== | ==Management== | ||
*[[Amiodarone]] 2 mg/kg bolus.<ref>[pubmed.ncbi.nlm.nih.gov/19632422], Kovacikova L. Amiodarone as a First-Line Therapy for Postoperative Junctional Ectopic Tachycardia. PubMed, National Library of Medicine, Aug 30, 2009.</ref> | |||
**If necessary, as continuous infusion at 10 to 15 mcg/kg/min | |||
==Disposition== | ==Disposition== | ||
==See Also== | ==See Also== | ||
*[[Paroxysmal supraventricular tachycardia]] | |||
*[[Tachycardia (Narrow)]] | |||
*[[ACLS: Tachycardia]] | |||
*[[PALS: Tachycardia]] | |||
==External Links== | ==External Links== | ||
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==References== | ==References== | ||
<references/> | <references/> | ||
[[Category:Cardiology]] | [[Category:Cardiology]] | ||
Latest revision as of 19:59, 15 March 2023
Background
- Rare
- Cardiac impulses originate at the AV junction
- AV node
- Bundle of His
- Also referred to as Junctional Ectopic Tachycardia (JET) or Congenital Ectopic Tachycardia (CJET) if present at birth
- Rate exceeds the upper limit seen in normal sinus rhythm
- In adults, >100 bpm
- In pediatric patients it varies by age until age 8 or 9 (see pediatric vital signs)
Junction Rhythm Classification
Arbitrarily classified by rate
- Junctional escape rhythm: 40-60 bpm
- Accelerated junctional rhythm: 60-100 bpm
- Junctional tachycardia: >100 bpm
Clinical Features
- Clinical features vary widely, diagnosis usually made via ECG
- Past medical hx may include recent cardiovascular surgery
Differential Diagnosis
Narrow-complex tachycardia
- Regular
- AV Node Independent
- Sinus tachycardia
- Atrial tachycardia (uni-focal or multi-focal)
- Atrial fibrillation
- Atrial flutter
- Idiopathic fascicular left ventricular tachycardia
- AV Node Dependent
- AV Node Independent
- Irregular
- Multifocal atrial tachycardia (MAT)
- Sinus tachycardia with frequent PACs, PJCs, PVCs
- Atrial fibrillation
- Atrial flutter with variable conduction
- Digoxin Toxicity
Wide-complex tachycardia
Assume any wide-complex tachycardia is ventricular tachycardia until proven otherwise (it is safer to incorrectly assume a ventricular dysrhythmia than supraventricular tachycardia with abberancy)
- Regular
- Monomorphic ventricular tachycardia
- PSVT with aberrant conduction:
- PSVT with bundle branch block^
- PSVT with accessory pathway
- Atrial flutter with bundle branch block^
- Sinus tachycardia with bundle branch block^
- Accelerated idioventricular rhythm (consider if less than or ~120 bpm)
- Metabolic
- Irregular
- Atrial fibrillation/atrial flutter with variable AV conduction AND bundle branch block^
- Atrial fibrillation/atrial flutter with variable AV conduction AND accessory pathway (e.g. WPW)
- Atrial fibrillation + hyperkalemia
- Polymorphic ventricular tachycardia
^Fixed or rate-related
Evaluation
- ECG findings
- P waves
- may be antegrade, retrograde, or absent depending on depolarization of the atrial relative to the ventricles
- QRS complexes
- Narrow in the absence of aberrancy
- P waves
- May be distinguished from AVNRT via Adenosine administration
- If JET is present, atrial depolarization will briefly terminate and reveal AV dissociation
- If AVNRT is present, conversion to sinus rhythm will likely occur
- Avoid administration in the setting of aberrancy
- JET will concomitant 3 degree AVB is rare
- Consider JET underlying causes to include
- Electrolyte abnormalities
- Acidosis
- Cardiovascular surgery within 24-48 hrs
Management
- Amiodarone 2 mg/kg bolus.[1]
- If necessary, as continuous infusion at 10 to 15 mcg/kg/min
Disposition
See Also
External Links
References
- ↑ [pubmed.ncbi.nlm.nih.gov/19632422], Kovacikova L. Amiodarone as a First-Line Therapy for Postoperative Junctional Ectopic Tachycardia. PubMed, National Library of Medicine, Aug 30, 2009.