Elsevier

American Heart Journal

Volume 62, Issue 6, December 1961, Pages 756-771
American Heart Journal

Clinical communication
Morphology of the human atrioventricular node, with remarks pertinent to its electrophysiology,☆☆

https://doi.org/10.1016/0002-8703(61)90664-0Get rights and content

Abstract

The morphology of the A-V node and its environs in man was studied in 81 hearts. Between the node and the endocardium of the right atrium are Purkinje fibers which may function as bypass tracts, allowing an impulse from the sinus node to circumvent the A-V node. This alternate pathway lends support to recent electrophysiologic studies which have suggested such a dual conduction system.

Because of the profuse interconnections of the normal A-V node fibers, the suggestion is made that the slight delay in impulse conduction observed in this region may be a multiple cancellation effect within the node. The same morphologic feature may conceivably combine with focal nodal disease to produce dual conduction inside the A-V node.

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    This research was supported in part by grants from the U.S. Public Health Service (H-5197) and the Michigan Heart Association.

    ☆☆

    A portion of this material was presented before the annual meeting of the Cardiac Electrophysiological Group, April 30, 1961, in Atlantic City, N. J.

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