Abstract
Histo-Pathological studies have demonstrated the essential focal nature of AV conduction disturbances, but current clinical concepts of heart block, derived from the scalar electrocardiogram, give little or no information as to the precise site within the conducting system where impulses are delayed or blocked. The His bundle electrogram resolves the complex P-R interval of scalar tracings into its various components. It can be used therefore to define the precise location and degree of block and this information permits detailed analysis of the underlying mechanisms to be attempted. New concepts of heart block based on measurements of the His bundle electrogram, are presented, in which heart block is classified into four main groups, identified by the site within the conducting system, where delay or block of impulses occurs. These are, (1) within the internodal atrial tracts, (Group I), (2) in the atrio-ventricular node, (Group II), and (3) within the fibres of the His-Purkinje system, (Group III). Cases with more than one site of disturbed conduction, are included in Group IV, and they can be identified by the His bundle electrogram alone. It is suggested that this new knowledge has important diagnostic and therapeutic applications, and these are discussed.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
