24 hour ECG

Features of the standard report

  • Predominant rhythm
  • Important observations – pauses, sustained tachycardias etc
  • Ventricular ectopics
  • Supraventricular ectopics
  • Bradycardias
  • Any other arrhythmias
  • Patient diary events

NB: a normal tape dose NOT rule out serious rhythm disturbance

Quantifying arrhythmias

  • Total beats per day example
    • 60 bpm x 60 minutes x 24 hours = 86400 beats per day
  • Very occassional: <10
  • Occasional: 11 – 1500
  • Moderate: 1500 – 2500
  • Frequent:  >2500
  • Very frequent: > 25% of total beats

Benign findings on tapes (generally)

  • Sinus arrhythmia
  • Sinus bradycardia or tachycardia
  • Ectopics (VE or SVEs)
  • Nocturnal conduction disturbances
  • Very short arrhythmias (few beats of SVT or AF)

Red flags

  • Complete heart block / 3rd degree AV block
  • SVT > 120 bpm
  • >1 episode of ventricular tachycardia
  • >5 beats of ventricular tachycardia
  • Sinus pauses > 3 seconds
  • Ventricular pauses > 3 seconds
  • Mobitz type 2
  • Diurnal heart rates < 40 bpm
  • Sustained ( >30 seconds) atrial fibrillation/flutter

Red flags in background

  • Abnormal heart structure
  • FH of unexplained sudden death
  • Unexplained syncope