| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Institute of Cardiovascular Science and Medicine, University of Hong Kong, Hong Kong Special Administrative Region, China; and 2 Montreal Heart Institute, Montreal, Quebec, Canada HIT IC8
Heart failure (HF) produces important
alterations in currents underlying cardiac repolarization, but the
transmural distribution of such changes is unknown. We therefore
recorded action potentials and ionic currents in cells isolated from
the endocardium, midmyocardium, and epicardium of the left ventricle
from dogs with and without tachypacing-induced HF. HF greatly increased
action potential duration (APD) but attenuated APD heterogeneity in the
three regions. Early afterdepolarizations (EADs) were observed in all
cell types of failing hearts but not in controls. Inward rectifier
K+ current (IK1) was homogeneously
reduced by ~41% (at 
60 mV) in the three cell types. Transient
outward K+ current (Ito1) was
decreased by 43-45% at +30 mV, and the slow component of the
delayed rectifier K+ current (IKs)
was significantly downregulated by 57%, 49%, and 58%, respectively,
in epicardial, midmyocardial, and endocardial cells, whereas the rapid
component of the delayed rectifier K+ current was not
altered. The results indicate that HF remodels electrophysiology in all
layers of the left ventricle, and the downregulation of
IK1, Ito1, and
IKs increases APD and favors occurrence of EADs.
heterogeneity; early afterdepolarizations; congestive heart failure; arrhythmias
This article has been cited by other articles:
|
|
 |
|
  T. Aiba, G. G. Hesketh, A. S. Barth, T. Liu, S. Daya, K. Chakir, V. L. Dimaano, T. P. Abraham, B. O'Rourke, F. G. Akar, et al. Electrophysiological Consequences of Dyssynchronous Heart Failure and Its Restoration by Resynchronization Therapy Circulation, March 10, 2009; 119(9): 1220 - 1230. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Michael, L. Xiao, X.-Y. Qi, D. Dobrev, and S. Nattel Remodelling of cardiac repolarization: how homeostatic responses can lead to arrhythmogenesis Cardiovasc Res, February 15, 2009; 81(3): 491 - 499. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. G Campbell, S. N Flaim, C. H Leem, and A. D McCulloch Mechanisms of transmurally varying myocyte electromechanics in an integrated computational model Phil Trans R Soc A, September 28, 2008; 366(1879): 3361 - 3380. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Bebarova, T. O'Hara, J. L. M. C. Geelen, R. J. Jongbloed, C. Timmermans, Y. H. Arens, L.-M. Rodriguez, Y. Rudy, and P. G. A. Volders Subepicardial phase 0 block and discontinuous transmural conduction underlie right precordial ST-segment elevation by a SCN5A loss-of-function mutation Am J Physiol Heart Circ Physiol, July 1, 2008; 295(1): H48 - H58. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Nattel, A. Maguy, S. Le Bouter, and Y.-H. Yeh Arrhythmogenic Ion-Channel Remodeling in the Heart: Heart Failure, Myocardial Infarction, and Atrial Fibrillation Physiol Rev, April 1, 2007; 87(2): 425 - 456. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. A. Armoundas, J. Rose, R. Aggarwal, B. D. Stuyvers, B. O'Rourke, D. A. Kass, E. Marban, S. R. Shorofsky, G. F. Tomaselli, and C. William Balke Cellular and molecular determinants of altered Ca2+ handling in the failing rabbit heart: primary defects in SR Ca2+ uptake and release mechanisms Am J Physiol Heart Circ Physiol, March 1, 2007; 292(3): H1607 - H1618. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X.-S. Liu, M. Jiang, M. Zhang, D. Tang, H. F. Clemo, R. S. D. Higgins, and G.-N. Tseng Electrical remodeling in a canine model of ischemic cardiomyopathy Am J Physiol Heart Circ Physiol, January 1, 2007; 292(1): H560 - H571. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. N. Obreztchikova, K. W. Patberg, A. N. Plotnikov, N. Ozgen, I. N. Shlapakova, A. V. Rybin, E. A. Sosunov, P. Danilo Jr., E. P. Anyukhovsky, R. B. Robinson, et al. IKr contributes to the altered ventricular repolarization that determines long-term cardiac memory Cardiovasc Res, July 1, 2006; 71(1): 88 - 96. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. W. Dilly, C. F. Rossow, V. S. Votaw, J. S. Meabon, J. L. Cabarrus, and L. F. Santana Mechanisms underlying variations in excitation-contraction coupling across the mouse left ventricular free wall J. Physiol., April 1, 2006; 572(1): 227 - 241. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Tsuji, S. Zicha, X.-Y. Qi, I. Kodama, and S. Nattel Potassium Channel Subunit Remodeling in Rabbits Exposed to Long-Term Bradycardia or Tachycardia: Discrete Arrhythmogenic Consequences Related to Differential Delayed-Rectifier Changes Circulation, January 24, 2006; 113(3): 345 - 355. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Fauconnier, A. Lacampagne, J.-M. Rauzier, G. Vassort, and S. Richard Ca2+-dependent reduction of IK1 in rat ventricular cells: A novel paradigm for arrhythmia in heart failure? Cardiovasc Res, November 1, 2005; 68(2): 204 - 212. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G.-L. Wang, G.-X. Wang, S. Yamamoto, L. Ye, H. Baxter, J. R Hume, and D. Duan Molecular mechanisms of regulation of fast-inactivating voltage-dependent transient outward K+ current in mouse heart by cell volume changes J. Physiol., October 15, 2005; 568(2): 423 - 443. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Xiong, Y. Tian, D. DiSilvestre, and G. F. Tomaselli Transmural Heterogeneity of Na+-Ca2+ Exchange: Evidence for Differential Expression in Normal and Failing Hearts Circ. Res., August 5, 2005; 97(3): 207 - 209. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Zicha, M. Fernandez-Velasco, G. Lonardo, N. L'Heureux, and S. Nattel Sinus node dysfunction and hyperpolarization-activated (HCN) channel subunit remodeling in a canine heart failure model Cardiovasc Res, June 1, 2005; 66(3): 472 - 481. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
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]
|
|
|
|
|
|
J. Rose, A. A. Armoundas, Y. Tian, D. DiSilvestre, M. Burysek, V. Halperin, B. O'Rourke, D. A. Kass, E. Marban, and G. F. Tomaselli Molecular correlates of altered expression of potassium currents in failing rabbit myocardium Am J Physiol Heart Circ Physiol, May 1, 2005; 288(5): H2077 - H2087. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Zicha, L. Xiao, S. Stafford, T. J. Cha, W. Han, A. Varro, and S. Nattel Transmural expression of transient outward potassium current subunits in normal and failing canine and human hearts J. Physiol., December 15, 2004; 561(3): 735 - 748. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. F. Tomaselli and D. P. Zipes What Causes Sudden Death in Heart Failure? Circ. Res., October 15, 2004; 95(8): 754 - 763. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
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]
|
|
|
|
 |
|
 D. Stilli, R. Berni, L. Bocchi, M. Zaniboni, F. Cacciani, A. Sgoifo, and E. Musso Vulnerability to ventricular arrhthmias and heterogeneity of action potential duration in normal rats Exp Physiol, July 1, 2004; 89(4): 387 - 396. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Ueda, D. P Zipes, and J. Wu Prior ischemia enhances arrhythmogenicity in isolated canine ventricular wedge model of long QT 3 Cardiovasc Res, July 1, 2004; 63(1): 69 - 76. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. M. Cordeiro, L. Greene, C. Heilmann, D. Antzelevitch, and C. Antzelevitch Transmural heterogeneity of calcium activity and mechanical function in the canine left ventricle Am J Physiol Heart Circ Physiol, April 1, 2004; 286(4): H1471 - H1479. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. G. Akar, R. C. Wu, I. Deschenes, A. A. Armoundas, V. Piacentino III, S. R. Houser, and G. F. Tomaselli Phenotypic differences in transient outward K+ current of human and canine ventricular myocytes: insights into molecular composition of ventricular Ito Am J Physiol Heart Circ Physiol, February 1, 2004; 286(2): H602 - H609. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Fernandez-Velasco, N. Goren, G. Benito, J. Blanco-Rivero, L. Bosca, and C. Delgado Regional distribution of hyperpolarization-activated current (If) and hyperpolarization-activated cyclic nucleotide-gated channel mRNA expression in ventricular cells from control and hypertrophied rat hearts J. Physiol., December 1, 2003; 553(2): 395 - 405. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
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]
|
|
|
|
|
|
H.-S. Wang and I. S Cohen Calcium channel heterogeneity in canine left ventricular myocytes J. Physiol., March 15, 2003; 547(3): 825 - 833. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
