---
abstract: "A 55 year old man with history of palpitation was referred for electrophysiologic study. Baseline ECG, physical examination and transthoracic echocardiographic study  were normal. Electrophysiologic study revealed normal AH and HV intervals. Pacing of right atrium with a cycle length of 300 msec showed  2:1 AV block. AH interval was 252 msec and the block was infra-his (Figure 1). With continual of right atrial pacing, one to one AV conduction with increasing AH interval to 282 msec and QRS widening (LBBB pattern) were being observed.  HV intervals during 2:1 block and during 1:1 AV conduction were normal.  What is the mechanism? Is it an abnormal finding in this patient?\n"
altloc:
  - http://www.ipej.org/0603/alasti2.htm
chapter: ~
commentary: ~
commref: ~
confdates: ~
conference: ~
confloc: ~
contact_email: ~
creators_id: []
creators_name:
  - family: Alasti
    given: Mohammad
    honourific: ''
    lineage: ''
  - family: Alizadeh
    given: Abolfath
    honourific: ''
    lineage: ''
  - family: Fazelifar
    given: Amirfarjam
    honourific: ''
    lineage: ''
  - family: Ali Sadr-Ameli
    given: Mohammad
    honourific: ''
    lineage: ''
date: 2006-07
date_type: published
datestamp: 2006-10-28
department: ~
dir: disk0/00/00/52/39
edit_lock_since: ~
edit_lock_until: ~
edit_lock_user: ~
editors_id: []
editors_name:
  - family: Singh
    given: Balbir
    honourific: ''
    lineage: ''
  - family: Lokhandwala
    given: Yash
    honourific: ''
    lineage: ''
  - family: Francis
    given: Johnson
    honourific: ''
    lineage: ''
  - family: Gupta
    given: Anup
    honourific: ''
    lineage: ''
  - family: Ghosh
    given: Joydeep
    honourific: ''
    lineage: ''
eprint_status: archive
eprintid: 5239
fileinfo: /style/images/fileicons/text_html.png;/5239/1/alasti2.htm|/style/images/fileicons/application_pdf.png;/5239/2/alasti2.pdf
full_text_status: public
importid: ~
institution: ~
isbn: ~
ispublished: pub
issn: ~
item_issues_comment: []
item_issues_count: 0
item_issues_description: []
item_issues_id: []
item_issues_reported_by: []
item_issues_resolved_by: []
item_issues_status: []
item_issues_timestamp: []
item_issues_type: []
keywords: "His-purkinje system; infra-his block\n"
lastmod: 2011-03-11 08:56:41
latitude: ~
longitude: ~
metadata_visibility: show
note: ~
number: 3
pagerange: 184-185
pubdom: TRUE
publication: Indian Pacing and Electrophysiology Journal
publisher: Indian Pacing and Electrophysiology Group
refereed: TRUE
referencetext: ~
relation_type: []
relation_uri: []
reportno: ~
rev_number: 14
series: ~
source: ~
status_changed: 2007-09-12 17:08:16
subjects:
  - ipej
succeeds: ~
suggestions: ~
sword_depositor: ~
sword_slug: ~
thesistype: ~
title: "Infra-His Block in a Normal Heart\n"
type: journalp
userid: 4424
volume: 6
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