A junctional rhythm starts in the area of the AV node when the sinus node slows or fails, so the heart beats at about 40 to 60 per minute with narrow QRS complexes. Faster forms suggest digoxin toxicity, ischemia or recent heart surgery.
Key symptoms
- Often none
- Fatigue, dizziness or fainting if the rate is slow
- Palpitations or pounding in the neck
- Shortness of breath or chest pain with underlying heart disease
What you find on exam
- Regular pulse, often slow
- Cannon a waves in the jugular veins
- Blood pressure and signs of poor perfusion
- Drug review: digoxin, beta blockers, calcium channel blockers
Tests
- 12-lead ECG: narrow QRS with absent, inverted or retrograde P waves
- Electrolytes, especially potassium and magnesium
- Digoxin level and troponin when relevant
- Thyroid tests; ambulatory monitor if episodes come and go
Treatment basics
- No treatment if stable and without symptoms
- Stop or reduce drugs that slow the heart
- Atropine or pacing if slow with poor perfusion
- Digoxin immune fab for digoxin toxicity
Red flags
- Low blood pressure, fainting or confusion
- Signs of digoxin toxicity: vomiting, visual changes, high potassium
- Chest pain or ECG signs of ischemia
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.