AJP - Heart Calcium Transients and Cell-Sarcomere
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Heart Circ Physiol 275: H1513-H1519, 1998;
0363-6135/98 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
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
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Suzuki, S.
Right arrow Articles by Suga, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Suzuki, S.
Right arrow Articles by Suga, H.
Vol. 275, Issue 5, H1513-H1519, November 1998

Ventricular contractility in atrial fibrillation is predictable by mechanical restitution and potentiation

Shunsuke Suzuki1, Junichi Araki1, Terumasa Morita2, Satoshi Mohri1, Takeshi Mikane1, Hiroki Yamaguchi2, Shunji Sano2, Tohru Ohe3, Masahisa Hirakawa4, and Hiroyuki Suga1

Departments of 1 Physiology II, 2 Cardiovascular Surgery, 3 Cardiovascular Medicine, and 4 Anesthesiology and Resuscitology, Okayama University Medical School, Okayama, 700-8558, Japan

We recently found that contractility (Emax) of an individual irregularly arrhythmic beat in electrically induced atrial fibrillation (AF) is reasonably predictable from the ratio of the preceding beat interval (RR1) to the beat interval immediately preceding RR1 (RR2) in the canine left ventricle. Moreover, the monotonically increasing relation between Emax and the RR1-to-RR2 ratio (RR1/RR2) passed through or by the mean arrhythmic beat Emax as well as the regular beat Emax at RR1/RR2 = 1. We hypothesized that this Emax-RR1/RR2 relation during irregular arrhythmia could be attributed to the basic characteristics of the mechanical restitution and potentiation. To test this, we adopted a known comprehensive equation describing the force restitution and potentiation as a function of two preceding beat intervals and simulated contractilities of irregular arrhythmic beats with randomized beat intervals on a computer. The simulated Emax-RR1/RR2 relation reasonably resembled the one that we recently observed experimentally, supporting our hypothesis. We therefore conclude that the primary mechanism underlying the varying contractilities of irregular beats in AF is mechanical restitution and potentiation.

irregular rhythm; arrhythmia; interval-force relation; contractility; calcium


This article has been cited by other articles:


Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
S. Mohri, J. Shimizu, G. Iribe, H. Ito, T. Morita, H. Yamaguchi, S. Sano, F. Kajiya, and H. Suga
Normal distribution of ventricular pressure-volume area of arrhythmic beats under atrial fibrillation in canine heart
Am J Physiol Heart Circ Physiol, April 1, 2005; 288(4): H1740 - H1746.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
T. Tabata, R. A. Grimm, J. Asada, Z. B. Popovic, H. Yamada, N. L. Greenberg, D. W. Wallick, Y. Zhang, S. Zhuang, K. A. Mowrey, et al.
Determinants of LV diastolic function during atrial fibrillation: beat-to-beat analysis in acute dog experiments
Am J Physiol Heart Circ Physiol, January 1, 2004; 286(1): H145 - H152.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
Z. B. Popovic', K. A. Mowrey, Y. Zhang, S. Zhuang, T. Tabata, D. W. Wallick, R. A. Grimm, J. D. Thomas, and T. N. Mazgalev
Slow rate during AF improves ventricular performance by reducing sensitivity to cycle length irregularity
Am J Physiol Heart Circ Physiol, December 1, 2002; 283(6): H2706 - H2713.
[Abstract] [Full Text] [PDF]

Home page
 HeartHome page
M Takagaki, P M McCarthy, M Chung, J Connor, R Dessoffy, Y Ochiai, M Howard, K Doi, M Kopcak, T N Mazgalev, et al.
Preload-adjusted maximal power: a novel index of left ventricular contractility in atrial fibrillation
Heart, August 1, 2002; 88(2): 170 - 176.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
T. Tabata, R. A. Grimm, N. L. Greenberg, D. A. Agler, K. A. Mowrey, D. W. Wallick, Y. Zhang, S. Zhuang, T. N. Mazgalev, and J. D. Thomas
Assessment of LV systolic function in atrial fibrillation using an index of preceding cardiac cycles
Am J Physiol Heart Circ Physiol, August 1, 2001; 281(2): H573 - H580.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online