Circulation, Vol 77, 1177-1184, Copyright © 1988 by American Heart Association
MR Franz and A Costard
To determine the normal relationship in vivo between action potential
duration (APD) and effective refractory period (ERP) over a large range of
steady-state cycle lengths (CLs) and to determine how a sodium
channel-blocking agent, quinidine, affects this relationship, we developed
a new contact electrode technique for simultaneous measurements of
monophasic action potentials and refractoriness at a single site in the
beating heart in situ. Recordings were made from left ventricular
epicardium in open-chest dogs during steady-state pacing at CLs from 220 to
600 msec both before and after therapeutic intravenous administration of
quinidine. During baseline both APD at 90% repolarization (APD90) and ERP
were linearly correlated to CL with nearly identical slopes: y = 0.24x CL +
83.0 (r = 1.0; p less than .0001) for APD90 and y = 0.22x CL + 82.3 (r =
1.0; p less than .0001) for ERP. Expressed in percent repolarization, ERP
coincided with a repolarization level of 79% to 83%, with no appreciable
influence of CL on this relationship. Quinidine increased APD90 by a small
but significant amount (8 to 12 msec), which was independent of CL. In
contrast, the effect on ERP of quinidine exhibited marked frequency
dependence (p less than .0002), producing progressively greater ERP
increase at shorter CLs, as compared with both baseline ERP and concomitant
APD90. The duration by which ERP exceeded APD90 reached 44 +/- 14 msec at a
CL of 220 msec.(ABSTRACT TRUNCATED AT 250 WORDS)
ARTICLES
Frequency-dependent effects of quinidine on the relationship between action potential duration and refractoriness in the canine heart in situ
Division of Cardiology, Stanford University School of Medicine, CA 94305.
This article has been cited by other articles:
 |
|
 |
|
  D. I. Leftheriotis, G. N. Theodorakis, D. Poulis, P. G. Flevari, E. G. Livanis, E. K. Iliodromitis, A. Papalois, and D. Th. Kremastinos The effects of 5-HT4 receptor blockade and stimulation, during six hours of atrial fibrillation Europace, January 1, 2005; 7(6): 560 - 568. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Kirchhof, H. Degen, M. R. Franz, L. Eckardt, L. Fabritz, P. Milberg, S. Laer, J. Neumann, G. Breithardt, and W. Haverkamp Amiodarone-Induced Postrepolarization Refractoriness Suppresses Induction of Ventricular Fibrillation J. Pharmacol. Exp. Ther., April 1, 2003; 305(1): 257 - 263. [Abstract] [Full Text]
|
|
|
|
 |
|
 F. Bode, M. Kilborn, P. Karasik, and M. R. Franz The repolarization-excitability relationship in the human right atrium is unaffected by cycle length, recording site and prior arrhythmias J. Am. Coll. Cardiol., March 1, 2001; 37(3): 920 - 925. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Dorian and D. Newman Rate dependence of the effect of antiarrhythmic drugs delaying cardiac repolarization: an overview Europace, January 1, 2000; 2(4): 277 - 285. [Abstract] [PDF]
|
|
|
|
 |
|
 A. Bauer, R. Becker, K. D. Freigang, J. C. Senges, F. Voss, A. Hansen, M. Muller, H. J. Lang, U. Gerlach, A. Busch, et al. Rate- and Site-Dependent Effects of Propafenone, Dofetilide, and the New IKs-Blocking Agent Chromanol 293b on Individual Muscle Layers of the Intact Canine Heart Circulation, November 23, 1999; 100(21): 2184 - 2190. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. R Franz Current status of monophasic action potential recording: theories, measurements and interpretations Cardiovasc Res, January 1, 1999; 41(1): 25 - 40. [Full Text] [PDF]
|
|
|
|
 |
|
 A. A. Grace and A. J. Camm Quinidine N. Engl. J. Med., January 1, 1998; 338(1): 35 - 45. [Full Text] [PDF]
|
|
|
|
|
|
E. A. Sosunov, E. P. Anyukhovsky, and M. R. Rosen Effects of Quinidine on Repolarization in Canine Epicardium, Midmyocardium, and Endocardium : I. In Vitro Study Circulation, December 2, 1997; 96(11): 4011 - 4018. [Abstract] [Full Text]
|
|
|
|
|
|
E. P. Anyukhovsky, E. A. Sosunov, S. J. Feinmark, and M. R. Rosen Effects of Quinidine on Repolarization in Canine Epicardium, Midmyocardium, and Endocardium : II. In Vivo Study Circulation, December 2, 1997; 96(11): 4019 - 4026. [Abstract] [Full Text]
|
|
|
|
|
|
S. D. Girouard, J. M. Pastore, K. R. Laurita, K. W. Gregory, and D. S. Rosenbaum Optical Mapping in a New Guinea Pig Model of Ventricular Tachycardia Reveals Mechanisms for Multiple Wavelengths in a Single Reentrant Circuit Circulation, February 1, 1996; 93(3): 603 - 613. [Abstract] [Full Text]
|
|
|
|
|
|
B. S. Koller, P. E. Karasik, A. J. Solomon, and M. R. Franz Relation Between Repolarization and Refractoriness During Programmed Electrical Stimulation in the Human Right Ventricle : Implications for Ventricular Tachycardia Induction Circulation, May 1, 1995; 91(9): 2378 - 2384. [Abstract] [Full Text]
|
|