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8 Junctional Tachycardia See Figure 20 for a representative ECG for junctional tachycardia and Figure 21 for the algorithm for ongoing management of junctional tachycardia. Junctional tachycardia is a rapid, occasionally irregular, narrow-complex tachycardia (with rates typically of 120 bpm to 220 bpm) (Figure 20). AV dissociation (often isorhythmic) may be seen, and when present, excludes the misdiagnosis of AVRT and makes AVNRT highly unlikely. Other SVTs are often misdiagnosed and misclassified as junctional tachycardia because of the frequent absence of demonstrable P waves in reentrant rhythms. Furthermore, when it is irregular, junctional tachycardia may be misdiagnosed as AF or MAT. The mechanism for junctional tachycardia is enhanced (abnormal) automaticity from an ectopic focus in the AV junction (including the His bundle).388 Junctional tachycardia is uncommon in adults388; it is typically seen in infants postoperatively, after cardiac surgery for congenital heart disease; this is also known as junctional ectopic tachycardia. As such, there is limited evidence with regard to diagnosis and management of junctional tachycardia in adult patients. Adults with junctional tachycardia typically have a relatively benign course, whereas infants and children with acquired or congenital junctional tachycardia have a high rate of death due to heart failure or an uncontrollable, incessant tachyarrhythmia. There are data to support the use of beta blockers, diltiazem, flecainide, procainamide, propafenone, and verapamil for the treatment of junctional tachycardia (see recommendations and references in Sections 8.1 and 8.2). The efficacy of amiodarone has been reported only in pediatric patients.389,390 Digoxin has not been well established as chronic therapy for junctional tachycardia. A related rhythm, nonparoxysmal junctional tachycardia (more commonly known as accelerated AV junctional rhythm), is far more common in adults than paroxysmal junctional tachycardia. The mechanism of nonparoxysmal junctional tachycardia is associated with automaticity or triggered activity. It occurs at a slower rate (70 bpm to 130 bpm) and is often due to digoxin toxicity391 or myocardial infarction.392,393 Treatment of this rhythm centers on addressing the underlying condition. In addition, there is some evidence that beta blockers,394 intravenous adenosine, or verapamil395 can terminate an accelerated junctional arrhythmia. A transient junction rhythm may be seen after slow-pathway ablation for AVNRT.396 8.1 Acute Treatment: Recommendations Recommendations for Acute Treatment of Junctional Tachycardia COR LOE Recommendations IIa C-LD 1. Intravenous beta blockers are reasonable for acute treatment in patients with symptomatic junctional tachycardia.388 See Online Data Supplement 19. In a series studying junctional tachycardia in adult patients, beta-blocker therapy—specifically intravenous propranolol—was found to be modestly effective in terminating and/or reducing the incidence of tachycardia.388 IIa C-LD 2. Intravenous diltiazem, procainamide, or verapamil is reasonable for acute treatment in patients with junctional tachycardia.397 See Online Data Supplement 19. There may be a limited role for intravenous diltiazem, procainamide, or verapamil in patients in whom beta blockers are ineffective. The literature supports the use of intravenous verapamil, alone or in combination with procainamide; less is known about diltiazem monotherapy.397 The addition of procainamide to propranolol may be more effective than propranolol monotherapy.388 Figure 14. Acute treatment of orthodromic AVRT. Colors correspond to Class of Recommendation in Table 1; drugs listed alphabetically. *For rhythms that break or recur spontaneously, synchronized cardioversion is not appropriate. AVRT indicates atrioventricular reentrant tachycardia; ECG, electrocardiogram; and IV, intravenous. Downloaded from http://ahajournals.org by on October 7, 2026