Accelerated Junctional Rhythm Heart Rate
Accelerated junctional rhythm is defined by a heart rate of 70 to 130 bpm originating from the AV junction. 11
Heart Rate Definition
The 2015 ACC/AHA/HRS guidelines clearly distinguish accelerated junctional rhythm (also called nonparoxysmal junctional tachycardia) from paroxysmal junctional tachycardia based on rate:
The key distinction is that accelerated junctional rhythm represents a slower junctional rate that exceeds the normal junctional escape rate (40-60 bpm) but remains below true tachycardia range.
Clinical Context
Accelerated junctional rhythm is far more common in adults than paroxysmal junctional tachycardia and has distinct clinical associations 11:
Common Etiologies:
- Digoxin toxicity (most important to recognize)
- Myocardial infarction
- Post-cardiac surgery (particularly valve replacement, occurring in ~33% of valve patients vs 13% of CABG patients) 2
- Acute myocarditis 3
- Acute rheumatic fever 4
Mechanism:
The rhythm results from enhanced automaticity or triggered activity in the AV junction, not the reentrant mechanisms seen in other SVTs 11.
Important Clinical Pitfall
Some studies define accelerated junctional rhythm at rates >55 bpm 2, but the authoritative ACC/AHA/HRS guideline uses the 70-130 bpm range 11. The lower threshold of 70 bpm represents a rate that clearly exceeds the intrinsic junctional escape rate and indicates pathologic acceleration.
Management Approach
Treatment focuses on addressing the underlying condition rather than the rhythm itself 11. The rhythm may terminate with:
- Beta blockers
- Intravenous adenosine
- Verapamil
However, identifying and treating the precipitating cause (especially digoxin toxicity or ischemia) takes priority over rhythm suppression.