High-resolution, three-dimensional fluorescent imaging reveals multilayer conduction pattern in the atrioventricular node.
BACKGROUND
The atrioventricular node (AVN) is the only normal electrical link between the upper and lower chambers of the heart. The AVN modulates transmission of impulses, thus coordinating the contraction of the atria and ventricles.


RESULTS
Structural and functional complexity, combined with the absence of adequate experimental techniques, has complicated attempts to directly evaluate the three-dimensional electrical activity of the AVN. Thus, despite a century of research by conventional electrophysiologic and histologic methods, even the existence of conduction through AVN is still debated.


CONCLUSIONS
Using a novel combination of microelectrode recordings and high resolution fluorescent imaging with voltage-sensitive dyes, we have for the first time clearly demonstrated three-dimensional conduction through the AVN.
Efimov
I R
IR
Department of Cardiology, Cleveland Clinic Foundation, Ohio 44195, USA.
Mazgalev
T N
TN
D000818:Animals; D001283:Atrioventricular Node / Q000033:anatomy & histology / Q000502:physiology*; D004594:Electrophysiology; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D008839:Microelectrodes; D011817:Rabbits