Article Text

Download PDFPDF
A new ECG sign of an accessory pathway in sinus rhythm: pseudo partial right bundle branch block
  1. E W Lau,
  2. G A Ng,
  3. M J Griffith
  1. Department of Cardiology, Queen Elizabeth Hospital, Edgbaston, Birmingham B15 2TH, UK
  1. Dr Lau. e-mail: e.w.lau{at}


It is clinically important to be able to detect the presence of an accessory pathway, as pre-excited atrial fibrillation is a well recognised cause of sudden cardiac death, for which there is a potential “cure” in the form of radiofrequency ablation of the pathway. The classic manifestations such as a shortened PR interval or delta waves may not always be present. In certain patients a pseudo partial right bundle block pattern—that is, an rSr′ complex in lead V1— may be the sole manifestation of a left sided accessory pathway. An electrophysiological mechanism is proposed for this pattern and it is suggested that this pattern may be used as a new ECG sign for diagnosing an accessory pathway in sinus rhythm.

  • accessory pathway
  • sinus rhythm
  • pseudo right bundle branch block

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.