Donate Help Contact The AHA Sign In Home
American Heart Association
Circulation
Search: search_blue_button Advanced Search
Circulation. 2002;105:1247-1253
Published online before print February 18, 2002, doi: 10.1161/hc1002.105231
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
105/10/1247    most recent
hc1002.105231v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowRequest Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Akar, F. G.
Right arrow Articles by Rosenbaum, D. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Akar, F. G.
Right arrow Articles by Rosenbaum, D. S.
Related Collections
Right arrow Animal models of human disease
Right arrow Arrythmias-basic studies

(Circulation. 2002;105:1247.)
© 2002 American Heart Association, Inc.


Basic Science Reports

Unique Topographical Distribution of M Cells Underlies Reentrant Mechanism of Torsade de Pointes in the Long-QT Syndrome

Fadi G. Akar, PhD; Gan-Xin Yan, MD PhD; Charles Antzelevitch, PhD; David S. Rosenbaum, MD

From the Heart and Vascular Research Center and Departments of Medicine and Biomedical Engineering (F.G.A., D.S.R.), MetroHealth Campus, Case Western Reserve University, Cleveland, Ohio, and Masonic Medical Research Laboratory (G.-X.Y., C.A.), Utica, NY.

Correspondence to David S. Rosenbaum, MD, Heart and Vascular Research Center, MetroHealth Campus, Case Western Reserve University, 2500 MetroHealth Dr, Hamann 322, Cleveland, OH 44109-1998. E-mail drosenbaum{at}metrohealth.org

Background Specific ion channel mutations underlie the congenital long-QT syndrome (LQTS). However, the mechanisms by which dysfunction at the molecular level translates into functional electrical instability leading to torsade de pointes (TdP) in LQTS are poorly understood.

Methods and Results The cellular basis of TdP was investigated using a novel approach of transmural optical imaging in the canine wedge preparation (n=14). The spatial organization of repolarization and arrhythmogenesis were determined in a surrogate model of LQT2. Action potentials were recorded simultaneously from 128 sites spanning the transmural wall of the left ventricle. In LQT2, QT interval prolongation was paralleled by an abrupt rise in transmural dispersion of repolarization (DOR) from 2.7±0.9 ms/mm (controls) to 12.2±2.1 ms/mm (LQT2). Islands of midmyocardial (M) cells formed zones of increased refractoriness in LQT2, producing steep spatial gradients of repolarization that were directly responsible for conduction block and self-sustained intramural reentrant circuits underlying TdP.

Conclusions These data provide direct evidence supporting the functional expression of M cells in intact myocardium and a central role for M cells in the development of reentrant TdP arrhythmias in LQTS.


Key Words: torsades de pointes • action potentials • arrhythmia • ion channels • mapping




This article has been cited by other articles:


Home page
Circ Arrhythmia ElectrophysiolHome page
S. Poelzing and D. S. Rosenbaum
The Modulated Dispersion Hypothesis Confirmed in Humans
Circ Arrhythmia Electrophysiol, April 1, 2009; 2(2): 100 - 101.
[Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
C. Antzelevitch
Role of spatial dispersion of repolarization in inherited and acquired sudden cardiac death syndromes
Am J Physiol Heart Circ Physiol, October 1, 2007; 293(4): H2024 - H2038.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Cell Physiol.Home page
A. Michailova, W. Lorentz, and A. McCulloch
Modeling transmural heterogeneity of KATP current in rabbit ventricular myocytes
Am J Physiol Cell Physiol, August 1, 2007; 293(2): C542 - C557.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
F. G. Akar, R. D. Nass, S. Hahn, E. Cingolani, M. Shah, G. G. Hesketh, D. DiSilvestre, R. S. Tunin, D. A. Kass, and G. F. Tomaselli
Dynamic changes in conduction velocity and gap junction properties during development of pacing-induced heart failure
Am J Physiol Heart Circ Physiol, August 1, 2007; 293(2): H1223 - H1230.
[Abstract] [Full Text] [PDF]


Home page
CirculationHome page
D. Jeyaraj, L. D. Wilson, J. Zhong, C. Flask, J. E. Saffitz, I. Deschenes, X. Yu, and D. S. Rosenbaum
Mechanoelectrical Feedback as Novel Mechanism of Cardiac Electrical Remodeling
Circulation, June 26, 2007; 115(25): 3145 - 3155.
[Abstract] [Full Text] [PDF]


Home page
J. Physiol.Home page
I. N. Sabir, M. J. Killeen, C. A. Goddard, G. Thomas, S. Gray, A. A. Grace, and C. L.-H. Huang
Transient alterations in transmural repolarization gradients and arrhythmogenicity in hypokalaemic Langendorff-perfused murine hearts
J. Physiol., May 15, 2007; 581(1): 277 - 289.
[Abstract] [Full Text] [PDF]


Home page
Cardiovasc ResHome page
S. T. Morita, D. P. Zipes, H. Morita, and J. Wu
Analysis of action potentials in the canine ventricular septum: No phenotypic expression of M cells
Cardiovasc Res, April 1, 2007; 74(1): 96 - 103.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
W. R. Mills, N. Mal, F. Forudi, Z. B. Popovic, M. S. Penn, and K. R. Laurita
Optical mapping of late myocardial infarction in rats
Am J Physiol Heart Circ Physiol, March 1, 2006; 290(3): H1298 - H1306.
[Abstract] [Full Text] [PDF]


Home page
PhysiologyHome page
T. Jespersen, M. Grunnet, and S.-P. Olesen
The KCNQ1 Potassium Channel: From Gene to Physiological Function
Physiology, December 1, 2005; 20(6): 408 - 416.
[Abstract] [Full Text] [PDF]


Home page
CirculationHome page
M. Shah, F. G. Akar, and G. F. Tomaselli
Molecular Basis of Arrhythmias
Circulation, October 18, 2005; 112(16): 2517 - 2529.
[Abstract] [Full Text] [PDF]


Home page
Physiol. Rev.Home page
J. M. Nerbonne and R. S. Kass
Molecular Physiology of Cardiac Repolarization
Physiol Rev, October 1, 2005; 85(4): 1205 - 1253.
[Abstract] [Full Text] [PDF]


Home page
Cardiovasc ResHome page
R. Schimpf, C. Wolpert, F. Gaita, C. Giustetto, and M. Borggrefe
Short QT syndrome
Cardiovasc Res, August 15, 2005; 67(3): 357 - 366.
[Abstract] [Full Text] [PDF]


Home page
Cardiovasc ResHome page
D. D. Spragg, F. G. Akar, R. H. Helm, R. S. Tunin, G. F. Tomaselli, and D. A. Kass
Abnormal conduction and repolarization in late-activated myocardium of dyssynchronously contracting hearts
Cardiovasc Res, July 1, 2005; 67(1): 77 - 86.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
F. G. Akar, R. C. Wu, G. J. Juang, Y. Tian, M. Burysek, D. DiSilvestre, W. Xiong, A. A. Armoundas, and G. F. Tomaselli
Molecular mechanisms underlying K+ current downregulation in canine tachycardia-induced heart failure
Am J Physiol Heart Circ Physiol, June 1, 2005; 288(6): H2887 - H2896.
[Abstract] [Full Text] [PDF]


Home page
Eur J Heart FailHome page
A. Pathak, D. Curnier, J. Fourcade, J. Roncalli, P. K. Stein, P. Hermant, M. Bousquet, P. Massabuau, J.-M. Senard, J.-L. Montastruc, et al.
QT dynamicity: a prognostic factor for sudden cardiac death in chronic heart failure
Eur J Heart Fail, March 2, 2005; 7(2): 269 - 275.
[Abstract] [Full Text] [PDF]


Home page
Cardiovasc ResHome page
P. Milberg, N. Reinsch, K. Wasmer, G. Monnig, J. Stypmann, N. Osada, G. Breithardt, W. Haverkamp, and L. Eckardt
Transmural dispersion of repolarization as a key factor of arrhythmogenicity in a novel intact heart model of LQT3
Cardiovasc Res, February 1, 2005; 65(2): 397 - 404.
[Abstract] [Full Text] [PDF]


Home page
Physiol. Rev.Home page
C. E. Clancy and R. S. Kass
Inherited and Acquired Vulnerability to Ventricular Arrhythmias: Cardiac Na+ and K+ Channels
Physiol Rev, January 1, 2005; 85(1): 33 - 47.
[Abstract] [Full Text] [PDF]


Home page
EuropaceHome page
S. N. Healy and A. D. McCulloch
An ionic model of stretch-activated and stretch-modulated currents in rabbit ventricular myocytes
Europace, January 1, 2005; 7(s2): S128 - S134.
[Abstract] [Full Text] [PDF]


Home page
CirculationHome page
F. Extramiana and C. Antzelevitch
Amplified Transmural Dispersion of Repolarization as the Basis for Arrhythmogenesis in a Canine Ventricular-Wedge Model of Short-QT Syndrome
Circulation, December 14, 2004; 110(24): 3661 - 3666.
[Abstract] [Full Text] [PDF]


Home page
Circ. Res.Home page
J. J. Saucerman, S. N. Healy, M. E. Belik, J. L. Puglisi, and A. D. McCulloch
Proarrhythmic Consequences of a KCNQ1 AKAP-Binding Domain Mutation: Computational Models of Whole Cells and Heterogeneous Tissue
Circ. Res., December 10, 2004; 95(12): 1216 - 1224.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
N. Ueda, D. P. Zipes, and J. Wu
Functional and transmural modulation of M cell behavior in canine ventricular wall
Am J Physiol Heart Circ Physiol, December 1, 2004; 287(6): H2569 - H2575.
[Abstract] [Full Text] [PDF]


Home page
Circ. Res.Home page
F. G. Akar, D. D. Spragg, R. S. Tunin, D. A. Kass, and G. F. Tomaselli
Mechanisms Underlying Conduction Slowing and Arrhythmogenesis in Nonischemic Dilated Cardiomyopathy
Circ. Res., October 1, 2004; 95(7): 717 - 725.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
S. Poelzing and D. S. Rosenbaum
Altered connexin43 expression produces arrhythmia substrate in heart failure
Am J Physiol Heart Circ Physiol, October 1, 2004; 287(4): H1762 - H1770.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
A. Burashnikov, S. Mannava, and C. Antzelevitch
Transmembrane action potential heterogeneity in the canine isolated arterially perfused right atrium: effect of IKr and IKur/Ito block
Am J Physiol Heart Circ Physiol, June 1, 2004; 286(6): H2393 - H2400.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
I. Libbus, X. Wan, and D. S. Rosenbaum
Electrotonic load triggers remodeling of repolarizing current Ito in ventricle
Am J Physiol Heart Circ Physiol, May 1, 2004; 286(5): H1901 - H1909.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
S. Poelzing, F. G. Akar, E. Baron, and D. S. Rosenbaum
Heterogeneous connexin43 expression produces electrophysiological heterogeneities across ventricular wall
Am J Physiol Heart Circ Physiol, May 1, 2004; 286(5): H2001 - H2009.
[Abstract] [Full Text] [PDF]


Home page
NEJMHome page
D. M. Roden
Drug-Induced Prolongation of the QT Interval
N. Engl. J. Med., March 4, 2004; 350(10): 1013 - 1022.
[Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
R. P. Katra, E. Pruvot, and K. R. Laurita
Intracellular calcium handling heterogeneities in intact guinea pig hearts
Am J Physiol Heart Circ Physiol, February 1, 2004; 286(2): H648 - H656.
[Abstract] [Full Text] [PDF]


Home page
CirculationHome page
M. Kimura, T. Kobayashi, S. Owada, K. Ashikaga, T. Higuma, S. Sasaki, A. Iwasa, S. Motomura, and K. Okumura
Mechanism of ST Elevation and Ventricular Arrhythmias in an Experimental Brugada Syndrome Model
Circulation, January 6, 2004; 109(1): 125 - 131.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
P. Smetana, V. N. Batchvarov, K. Hnatkova, A. J. Camm, and M. Malik
Ventricular gradient and nondipolar repolarization components increase at higher heart rate
Am J Physiol Heart Circ Physiol, January 1, 2004; 286(1): H131 - H136.
[Abstract] [Full Text] [PDF]


Home page
Circ. Res.Home page
D. M. Roden
A Surprising New Arrhythmia Mechanism in Heart Failure
Circ. Res., October 3, 2003; 93(7): 589 - 591.
[Full Text] [PDF]


Home page
Circ. Res.Home page
F. G. Akar and D. S. Rosenbaum
Transmural Electrophysiological Heterogeneities Underlying Arrhythmogenesis in Heart Failure
Circ. Res., October 3, 2003; 93(7): 638 - 645.
[Abstract] [Full Text] [PDF]


Home page
CirculationHome page
J. M. Di Diego, L. Belardinelli, and C. Antzelevitch
Cisapride-Induced Transmural Dispersion of Repolarization and Torsade de Pointes in the Canine Left Ventricular Wedge Preparation During Epicardial Stimulation
Circulation, August 26, 2003; 108(8): 1027 - 1033.
[Abstract] [Full Text] [PDF]


Home page
Circ. Res.Home page
K. R. Laurita, R. Katra, B. Wible, X. Wan, and M. H. Koo
Transmural Heterogeneity of Calcium Handling in Canine
Circ. Res., April 4, 2003; 92(6): 668 - 675.
[Abstract] [Full Text] [PDF]


Home page
Br J AnaesthHome page
P. D. Booker, S. D. Whyte, and E. J. Ladusans
Long QT syndrome and anaesthesia
Br. J. Anaesth., March 1, 2003; 90(3): 349 - 366.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
J. Wu and D. P. Zipes
Transmural reentry triggered by epicardial stimulation during acute ischemia in canine ventricular muscle
Am J Physiol Heart Circ Physiol, November 1, 2002; 283(5): H2004 - H2011.
[Abstract] [Full Text] [PDF]


Home page
Eur Heart JHome page
C. Antzelevitch
Sympathetic modulation of the long QT syndrome
Eur. Heart J., August 2, 2002; 23(16): 1246 - 1252.
[PDF]