Accelerated idioventricular rhythm

Background

  • Results when rate of an ectopic ventricular pacemaker exceeds sinus node
  • Usually benign,self limiting
  • Terminology
    • Idioventricular rhythm: 20-40 bpm
    • Accelerated idoventricular rhythm: 40-120 bpm
    • Ventricular tachycardia: >120 bpm

Causes

Clinical Features

Differential Diagnosis

Wide-complex tachycardia

Assume any wide-complex tachycardia is ventricular tachycardia until proven otherwise (it is safer to incorrectly assume a ventricular dysrhythmia than supraventricular tachycardia with abberancy)

^Fixed or rate-related

Palpitations

Evaluation

ECG features

  • Regular rhythm
  • Rate 50-110 bpm
  • Three or more ventricular complexes
  • QRS complexes >120ms
  • Fusion and capture beats

Management

  • AIVR is a benign rhythm in most settings and does not usually require treatment
  • Self limiting and resolves when sinus rate exceeds that of the ventricular foci
  • Antiarrhythmics may cause precipitous haemodynamic deterioration and should be avoided
  • Treat the underlying cause: e.g. correct electrolytes, restore myocardial perfusion
  • Patients with low-cardiac-output states (e.g. severe biventricular failure) may benefit from restoration of AV synchrony to restore atrial kick – in this case atropine may be trialled to increase sinus rate and AV conduction

Disposition

  • Normally outpatient

See Also

External Links

References