Reconstruction of the human atrioventricular node

Abstract

Abstract The right atrioventricular junction and A‐V node area in each of five human hearts was studied histologically in serial sections. The A‐V node of a 54‐year old female was reconstructed in four colors to provide a three‐dimensional model of cardiac relationships, blood supply, and nodal configuration. The nodal fibers demonstrated two laminations. A superficial layer was composed of longitudinally oriented fibers, whereas a deeper layer was composed of oblique and transversely directed fibers. The atrioventricular bundle fibers were always continuous with nodal fibers of the deeper portion of the A‐V node. Atrionodal fiber junctions occur along the superior, endocardial and inferior borders of the A‐V node and impart to these surfaces a spiked appearance. The potential significance of A‐V node structure to atrial cardiac conduction is presented.