- Sinus arrhythmia
- Sinus rhythm
- PR – Normal (~200ms)
- QRS – Normal (80ms)
- QT – 410ms (QTc Bazette 370ms)
- Early R wave transisition
- Borderline voltage criteria LVH
- V1 S + V5 R ~35mm
- No non-voltage criteria present
- Sinus bradycardia with sinus arrhythmia
Considerations with sinus bradycardia
I get asked to review many ECG’s that show sinus bradycardia and there are a few considerations in these cases including:
- Is the patient symptomatic ?
- Is this ‘normal’ for the patient ?
- What is / could be the cause ?
Regarding symptoms these may be the reason for an Emergency Department attendance or more insidious and can include:
- Light headedness
- Decreased exercise tolerant
- Chest pain
There are multiple potential causes of bradycardia including:
- Physiological – athletes or during sleep
- Increased vagal tone – nausea, vomiting, pain
- Drug effect / toxicity – inc, digoxin, beta-blockers, calcium channel blockers
- Environmental – hypothermia
- Endocrine – hypothyroid
- Sinus node dysfunction
- Sleep apnoea
References / Further Reading
Life in the Fast Lane
- Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.