(Circulation. 1996;94:571-577.)
© 1996 American Heart Association, Inc.
Articles |
Atrioventricular Junctional Tissue
Discrepancy Between Histological and Electrophysiological Characteristics
the Departments of Clinical and Experimental Cardiology (J.M.T. de B., J.T.V., P.L., B.T., M.J.J.), Anatomy and Embryology (A.F.M.M., J.L.M.V.), and Cardiovascular Pathology (A.E.B.), Academic Medical Center; the Interuniversity Cardiology Institute of the Netherlands, Amsterdam; and the Cardiology Department (M.A.M.), Royal Prince Alfred Hospital, Sydney, Australia.
Correspondence to Dr Mark McGuire, Cardiology Department, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia.
Background Previous work has demonstrated that cells with AV nodal-type action potentials are not confined to Koch's triangle but may extend along the AV orifices. The aim of this study was to examine the histological and electrophysiological characteristics of this tissue.
Methods and Results Studies were performed in isolated, blood-perfused dog and pig hearts. Microelectrode recordings revealed cells with nodal-type action potentials around the tricuspid and mitral valve rings. These cells were found within 1 to 2 mm of the valve annuli. A zone of cells with intermediate action potentials, 
1 cm wide, separated cells with nodal-type action potentials from cells with atrial-type action potentials in the body of the atria. In cells with nodal-type action potentials, adenosine caused a reduction in action potential amplitude (49±2 versus 33±2 mV, mean±SE; P<.001), upstroke velocity (2.5±0.2 versus 2.0±0.2 V/s, P<.05), and duration (150±4 versus 96±8 ms, P<.001). The light microscopic appearance of AV junctional cells was similar to that of myocytes in the body of the atrium. A polyclonal antibody raised against connexin-43 bound to atrial and ventricular tissue but not to the AV junctional tissue or AV nodal region. The absence of connexin-43 correlated with the sites of cells with nodal-like action potentials. With pacing techniques, the AV junctional tissue in the region of the posterior AV nodal approaches could be electrically dissociated from atrial, AV nodal, and ventricular tissue. AV nodal echoes were induced with ventricular pacing in three dog hearts. In each case, retrograde conduction was through the slow pathway, and anterograde conduction was through the fast pathway. During echoes, activation of AV junctional cells preceded atrial activation during retrograde slow pathway conduction, but these cells were not activated during anterograde fast pathway conduction.
Conclusions AV junctional cells around both annuli are histologically similar to atrial cells but resemble nodal cells in their cellular electrophysiology, response to adenosine, and lack of connexin-43. The light microscopic appearance of AV junctional cells is a poor guide to their action potential characteristics. The AV junctional cells in the posterior AV nodal approaches appear to participate in slow pathway conduction. These cells may be the substrate of the slow "AV nodal" pathway.
Key Words: atrioventricular node • tachyarrhythmias • electrophysiology • catheter ablation • action potential
This article has been cited by other articles:
 |
|
 |
|
  D. Steven, K. C. Roberts-Thomson, J. Seiler, K. Inada, U. B. Tedrow, R. N. Mitchell, P. S. Sobieszczyk, A. C. Eisenhauer, G. S. Couper, and W. G. Stevenson Ventricular Tachycardia Arising From the Aortomitral Continuity in Structural Heart Disease: Characteristics and Therapeutic Considerations for an Anatomically Challenging Area of Origin Circ Arrhythm Electrophysiol, December 1, 2009; 2(6): 660 - 666. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. R. Boyett \#8216;And the beat goes on' The cardiac conduction system: the wiring system of the heart Exp Physiol, October 1, 2009; 94(10): 1035 - 1049. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Weber, K. P. Letsas, T. Arentz, and D. Kalusche Adenosine sensitive focal atrial tachycardia originating from the non-coronary aortic cusp Europace, June 1, 2009; 11(6): 823 - 826. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. M. Christoffels and A. F.M. Moorman Development of the Cardiac Conduction System: Why Are Some Regions of the Heart More Arrhythmogenic Than Others? Circ Arrhythm Electrophysiol, April 1, 2009; 2(2): 195 - 207. [Full Text] [PDF]
|
|
|
|
|
|
T.-a. Matsuyama, S. Inoue, K. Tanno, M. Makino, G. Ogawa, T. Sakai, Y. Kobayashi, T. Katagiri, and H. Ota Ectopic nodal structures in a patient with atrial tachycardia originating from the mitral valve annulus Europace, November 1, 2006; 8(11): 977 - 979. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Yamamoto, H. Dobrzynski, J. Tellez, R. Niwa, R. Billeter, H. Honjo, I. Kodama, and M. R. Boyett Extended atrial conduction system characterised by the expression of the HCN4 channel and connexin45 Cardiovasc Res, November 1, 2006; 72(2): 271 - 281. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Kazemi, A. Arya, M. Haghjoo, and M. A Sadr-Ameli Coincident atrioventricular nodal reentrant and idiopathic ventricular tachycardia. Asian Cardiovasc Thorac Ann, August 1, 2006; 14(4): 284 - 288. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M.R.M. Jongbloed, M.C.E.F. Wijffels, M.J. Schalij, N.A. Blom, R.E. Poelmann, A. van der Laarse, M.M.T. Mentink, Z. Wang, G.I. Fishman, and A.C. Gittenberger-de Groot Development of the Right Ventricular Inflow Tract and Moderator Band: A Possible Morphological and Functional Explanation for Mahaim Tachycardia Circ. Res., April 15, 2005; 96(7): 776 - 783. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F G Cosio Should ablation be the first line treatment for supraventricular arrhythmias? Heart, January 1, 2005; 91(1): 5 - 6. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. D. Gonzalez, L. J. Contreras, M. R.M. Jongbloed, J. Rivera, T. P. Donahue, A. B. Curtis, M. S. Bailey, J. B. Conti, G. I. Fishman, M. J. Schalij, et al. Left Atrial Tachycardia Originating From the Mitral Annulus-Aorta Junction Circulation, November 16, 2004; 110(20): 3187 - 3192. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. M.H Hoogaars, A. Tessari, A. F.M Moorman, P. A.J de Boer, J. Hagoort, A. T Soufan, M. Campione, and V. M Christoffels The transcriptional repressor Tbx3 delineates the developing central conduction system of the heart Cardiovasc Res, June 1, 2004; 62(3): 489 - 499. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. G. KLEBER and Y. RUDY Basic Mechanisms of Cardiac Impulse Propagation and Associated Arrhythmias Physiol Rev, April 1, 2004; 84(2): 431 - 488. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. L. Wit Atrioventricular Nodal Electrophysiology: Still Exciting After All These Years Circ. Res., November 28, 2003; 93(11): 1018 - 1019. [Full Text] [PDF]
|
|
|
|
|
|
H. Dobrzynski, V. P. Nikolski, A. T. Sambelashvili, I. D. Greener, M. Yamamoto, M. R. Boyett, and I. R. Efimov Site of Origin and Molecular Substrate of Atrioventricular Junctional Rhythm in the Rabbit Heart Circ. Res., November 28, 2003; 93(11): 1102 - 1110. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. F. M. MOORMAN and V. M. CHRISTOFFELS Cardiac Chamber Formation: Development, Genes, and Evolution Physiol Rev, October 1, 2003; 83(4): 1223 - 1267. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Loh, S. Y. Ho, T. Kawara, R. N.W. Hauer, M. J. Janse, G. Breithardt, and J. M.T. de Bakker Reentrant Circuits in the Canine Atrioventricular Node During Atrial and Ventricular Echoes: Electrophysiological and Histological Correlation Circulation, July 15, 2003; 108(2): 231 - 238. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. M. Kistler, P. Sanders, A. Hussin, J. B. Morton, J. K. Vohra, P. B. Sparks, and J. M. Kalman Focal atrial tachycardia arising from the mitral annulus: Electrocardiographic and electrophysiologic characterization J. Am. Coll. Cardiol., June 18, 2003; 41(12): 2212 - 2219. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. P. Nikolski, S. A. Jones, M. K. Lancaster, M. R. Boyett, and I. R. Efimov Cx43 and Dual-Pathway Electrophysiology of the Atrioventricular Node and Atrioventricular Nodal Reentry Circ. Res., March 7, 2003; 92(4): 469 - 475. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Kautzner, R. Cihák, V. Vancura, and J. Bytesník Coincidence of idiopathic ventricular outflow tract tachycardia and atrioventricular nodal reentrant tachycardia Europace, January 1, 2003; 5(3): 215 - 220. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Iwai, S. M. Markowitz, K. M. Stein, S. Mittal, D. J. Slotwiner, M. K. Das, J. D. Cohen, S. C. Hao, and B. B. Lerman Response to Adenosine Differentiates Focal From Macroreentrant Atrial Tachycardia: Validation Using Three-Dimensional Electroanatomic Mapping Circulation, November 26, 2002; 106(22): 2793 - 2799. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Franco and J. M. Icardo Molecular characterization of the ventricular conduction system in the developing mouse heart: topographical correlation in normal and congenitally malformed hearts Cardiovasc Res, February 1, 2001; 49(2): 417 - 429. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Loh and G Breithardt 'Slow pathway' ablation in patients with atrioventricular nodal reentrant tachycardia: do we understand what we are doing? Eur. Heart J., January 1, 2001; 22(1): 19 - 21. [PDF]
|
|
|
|
|
|
J. M. T. de Bakker, P. Loh, M.e. Hocini, B. Thibault, and M. J. Janse Double component action potentials in the posterior approach to the atrioventricular node: do they reflect activation delay in the slow pathway? J. Am. Coll. Cardiol., August 1, 1999; 34(2): 570 - 577. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Medkour, A. E. Becker, K. Khalife, and J. Billette Anatomic and Functional Characteristics of a Slow Posterior AV Nodal Pathway : Role in Dual-Pathway Physiology and Reentry Circulation, July 14, 1998; 98(2): 164 - 174. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. A. Bednar, S. L. Gaul, T. G. Hamill, M. S. Egbertson, J. A. Shafer, G. D. Hartman, R. J. Gould, and B. Bednar Identification of Low Molecular Weight GP IIb/IIIa Antagonists That Bind Preferentially to Activated Platelets J. Pharmacol. Exp. Ther., June 1, 1998; 285(3): 1317 - 1326. [Abstract] [Full Text]
|
|
|
|
|
|
A. F.M. Moorman, F. de Jong, M. M.F.J. Denyn, and W. H. Lamers Development of the Cardiac Conduction System Circ. Res., April 6, 1998; 82(6): 629 - 644. [Full Text] [PDF]
|
|