This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hashimoto, H. Articles by Nakashima, M. Search for Related Content PubMed PubMed Citation Articles by Hashimoto, H. Articles by Nakashima, M.

Circulation, Vol 68, 667-672, Copyright © 1983 by American Heart Association

ARTICLES

Effects of calcium antagonists on the electrical alternans of the ST segment and on associated mechanical alternans during acute coronary occlusion in dogs

H Hashimoto, K Suzuki, S Miyake and M Nakashima

Effects of calcium antagonists on the ST alternans and associated mechanical alternans during acute coronary occlusion were examined in anesthetized dogs. The heart rate was fixed by atrial pacing. The intravenous administration of 0.2 mg/kg verapamil attenuated the ST alternans as did 0.5 mg/kg diltiazem. Although these drugs significantly attenuated TQ depression during occlusion, the attenuation was observed after a longer period of occlusion and when the degree of TQ depression was comparable to that during the control occlusion. Nifedipine, 0.03 mg/kg, slightly attenuated the ST alternans, but 0.5 mg/kg dipyridamole had no effect. These results support the idea that slow inward currents are involved in the ST alternans. On the other hand, the mechanical alternans was attenuated in six of 11 dogs. It is probable that factors other than the electrical alternans may also contribute to the mechanical alternans.

This article has been cited by other articles:

				Y.-W. Qian, R. J. Sung, S.-F. Lin, R. Province, and W. T. Clusin Spatial heterogeneity of action potential alternans during global ischemia in the rabbit heart Am J Physiol Heart Circ Physiol, December 1, 2003; 285(6): H2722 - H2733. [Abstract] [Full Text] [PDF]

				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]

				D. E Euler Cardiac alternans: mechanisms and pathophysiological significance Cardiovasc Res, June 1, 1999; 42(3): 583 - 590. [Full Text] [PDF]

				H. Tachibana, M. Yamaki, I. Kubota, T. Watanabe, S. Yamauchi, and H. Tomoike Intracoronary Flecainide Induces ST Alternans and Reentrant Arrhythmia on Intact Canine Heart : A Role of 4-Aminopyridine–Sensitive Current Circulation, March 30, 1999; 99(12): 1637 - 1643. [Abstract] [Full Text] [PDF]

				T. Kwan, A. Feit, M. Alam, E. Afflu, L. T. Clark, and T. Kwan ST-T Alternans and Myocardial Ischemia Angiology, March 1, 1999; 50(3): 217 - 222. [Abstract] [PDF]

				H. Tachibana, I. Kubota, M. Yamaki, T. Watanabe, and H. Tomoike Discordant S-T alternans contributes to formation of reentry: a possible mechanism of reperfusion arrhythmia Am J Physiol Heart Circ Physiol, July 1, 1998; 275(1): H116 - H121. [Abstract] [Full Text] [PDF]

				Y. Wu and W. T. Clusin Calcium transient alternans in blood-perfused ischemic hearts: observations with fluorescent indicator Fura Red Am J Physiol Heart Circ Physiol, November 1, 1997; 273(5): H2161 - H2169. [Abstract] [Full Text] [PDF]

				S. Okamoto, M. Inden, T. Konishi, and T. Nakano ST Segment Alternans During Percutaneous Transluminal Coronary Angioplasty A Case Report Angiology, January 1, 1991; 42(1): 30 - 34. [Abstract] [PDF]