From the Guidelines
Junctional rhythm is a cardiac rhythm that originates from the atrioventricular (AV) junction, typically generating a heart rate between 40-60 beats per minute, and is characterized by absent, inverted, or retrograde P waves, with a normal QRS complex unless there is concurrent bundle branch block. This rhythm occurs when the sinoatrial (SA) node fails to function properly or when conduction from the SA node is blocked, and the AV junction takes over as the heart's pacemaker 1. Junctional rhythms can be classified as passive (escape) or active (accelerated), with common causes including medication effects, electrolyte imbalances, inferior myocardial infarction, and cardiac surgery.
Characteristics of Junctional Rhythm
- Heart rate: 40-60 beats per minute
- P waves: absent, inverted, or retrograde
- QRS complex: normal unless there is concurrent bundle branch block
- Causes: medication effects, electrolyte imbalances, inferior myocardial infarction, cardiac surgery
Management of Junctional Rhythm
- Oral beta blockers are reasonable for ongoing management in patients with junctional tachycardia 2
- Oral diltiazem or verapamil may be used as an alternative to beta blockers 2
- Flecainide or propafenone may be considered in patients without structural heart disease or ischemic heart disease 3
- Catheter ablation may be reserved for highly symptomatic patients in whom medical therapy is ineffective or contraindicated 3
Key Considerations
- Addressing the underlying cause of the junctional rhythm is essential
- Symptomatic patients with slow junctional rhythms may require atropine or temporary/permanent pacing
- Junctional tachycardia is uncommon in adults, but can be seen in infants postoperatively after cardiac surgery for congenital heart disease 1