|
| HOME | SUBSCRIPTIONS | CURRENT ISSUE | PAST ISSUES | CARDIOSOURCE | SEARCH | HELP | FEEDBACK |
|
|
|
|||||||||
|
|||||||||||
|
J Am Coll Cardiol, 1988; 11:1327-1336 © 1988 by the American College of Cardiology Foundation |
Krannert Institute of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis 46202.
The purpose of this study was to investigate the immediate effects of an increase in atrial pressure on atrial refractoriness by determining the relation between the atrial pressure and effective refractory period of the atrium. In 21 open chest anesthetized dogs, after the blocking of atrioventricular (AV) conduction by formalin injection, the left atrium and left ventricle were paced sequentially at a fixed cycle length of 300 ms. The AV interval was varied from 0 to 280 ms in 20 ms steps during the recording of aortic and left atrial pressures and refractory period of the left atrium. Mean left atrial pressure was lowest (8.0 +/- 0.4 mm Hg, all values mean +/- SEM) at an AV interval of 47 +/- 3 ms, when refractory period was 135.5 +/- 2.6 ms. Mean left atrial pressure was highest (13.3 +/- 0.5 mm Hg) at an AV interval of 147 +/- 5 ms, when refractory period was 137.9 +/- 2.4 ms (p less than 0.01). Left atrial diameter measured by echocardiography increased from 33.7 +/- 1.8 mm at an AV interval of 47 ms to 37.8 +/- 1.8 mm (p less than 0.01, n = 10) at an AV interval of 147 ms, and mean aortic pressure decreased from 109 +/- 4 to 101 +/- 4 mm Hg. After surgical decentralization of vagal and sympathetic innervation to eliminate baroreflex influence on refractoriness, left atrial refractory period prolonged from 141.6 +/- 3.4 to 145.4 +/- 3.4 ms (p less than 0.01) when mean left atrial pressure increased from 9.5 +/- 0.4 to 15.2 +/- 0.6 mm Hg. A similar relation was noted between right atrial pressure and right atrial refractory period (n = 10) and between left atrial pressure and refractory period of the interatrial septum (n = 12). In six chronically instrumented conscious dogs, left atrial refractory period prolonged from 116.3 +/- 2.3 to 124.2 +/- 1.7 ms (p less than 0.01) when mean left atrial pressure increased from 4.0 +/- 0.8 to 9.0 +/- 0.3 mm Hg. Therefore, an increase in atrial pressure lengthens refractory period of both atria and the interatrial septum in anesthetized and conscious dogs.
This article has been cited by other articles:
|
|
 |
|
  H.-R. Neuberger, U. Schotten, S. Verheule, S. Eijsbouts, Y. Blaauw, A. van Hunnik, and M. Allessie Development of a Substrate of Atrial Fibrillation During Chronic Atrioventricular Block in the Goat Circulation, January 4, 2005; 111(1): 30 - 37. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Padeletti, N. Musilli, M. C. Porciani, A. Colella, L. Di Biase, G. Ricciardi, P. Pieragnoli, A. Michelucci, and G. Gensini Atrial fibrillation and cardiac resynchronization therapy: the MASCOT study Europace, January 1, 2003; 5(s1): S49 - S54. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. F Bosch and S. Nattel Cellular electrophysiology of atrial fibrillation Cardiovasc Res, May 1, 2002; 54(2): 259 - 269. [Full Text] [PDF]
|
|
|
|
|
|
A. Yamada, J. Hayano, S. Sakata, A. Okada, S. Mukai, N. Ohte, and G. Kimura Reduced Ventricular Response Irregularity Is Associated With Increased Mortality in Patients With Chronic Atrial Fibrillation Circulation, July 18, 2000; 102(3): 300 - 306. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. R Franz Mechano-electrical feedback Cardiovasc Res, January 14, 2000; 45(2): 263 - 266. [Full Text] [PDF]
|
|
|
|
|
|
P. B. Sparks, H. G. Mond, J. K. Vohra, S. Jayaprakash, and J. M. Kalman Electrical Remodeling of the Atria Following Loss of Atrioventricular Synchrony : A Long-Term Study in Humans Circulation, November 2, 1999; 100(18): 1894 - 1900. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. C. E. F. Wijffels, C. J. H. J. Kirchhof, R. Dorland, J. Power, and M. A. Allessie Electrical Remodeling due to Atrial Fibrillation in Chronically Instrumented Conscious Goats : Roles of Neurohumoral Changes, Ischemia, Atrial Stretch, and High Rate of Electrical Activation Circulation, November 18, 1997; 96(10): 3710 - 3720. [Abstract] [Full Text]
|
|
|
|
|
|
F. Ravelli and M. Allessie Effects of Atrial Dilatation on Refractory Period and Vulnerability to Atrial Fibrillation in the Isolated Langendorff-Perfused Rabbit Heart Circulation, September 2, 1997; 96(5): 1686 - 1695. [Abstract] [Full Text]
|
|
|
|
|
|
D. P. Zipes Atrial Fibrillation: A Tachycardia-Induced Atrial Cardiomyopathy Circulation, February 4, 1997; 95(3): 562 - 564. [Full Text]
|
|
| HOME | SUBSCRIPTIONS | CURRENT ISSUE | PAST ISSUES | CARDIOSOURCE | SEARCH | HELP | FEEDBACK |
