ECG library
Supraventricular tachycardia in an infant
core3 months old· infantA 3-month-old brought in because she 'will not feed and looks grey'. She has been irritable for a day. Rate 244, fixed, whatever anyone does.
25 mm/s · 10 mm/mV · synthetic tracing
100%
Calipers:2000 ms50.0 small boxes30 bpm if R-RDrag the orange markers. One small box = 40 ms.
Key findings
- Rate above 220, absolutely regular
- No visible P waves
- Presentation is feeding, pallor and irritability
Learning points
- Infants present SVT late, after hours or days, as poor feeding, pallor, sweating with feeds, or heart failure; the rate is found, not reported.
- First response is a vagal manoeuvre (ice to the face for an infant), then adenosine with a rapid flush and the ECG running; a shocked infant is cardioverted. Doses are institutional and are not stated here.
- Verapamil is avoided in infants. After conversion, look for pre-excitation on the sinus tracing.
Connected