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Abstract
Controversy has existed concerning the value of nitroglycerin therapy in acute myocardial
infarction. With use of Walton-Brodie strain gauge arches and mercury-in-Silastic
segment length gauges, the effects of nitroglycerin (30 μg/kg intravenously) were
studied on local tension and length characteristics of the ischemic, border and nonischemic
zones of the left ventricle in 10 open chest dogs. In the nonischemic zone total tension
increased to 144.8 ± 13.6 (mean ± standard error of the mean) percent (P <0.005) of control levels, and segment length decreased to 79.4 ± 4.4 percent (P <0.01) with infusion of nitroglycerin 15 to 30 minutes after coronary ligation. Changes
were similar in the groups given nitroglycerin 45 to 60 minutes and 2 to 3 hours after
ligation. The border zone exhibited an increase in total tension to 132.3 ± 8.4 percent
(P <0.005) of control level and a decrease in segment length to 79.0 ± 2.4 percent (P <0.001) in the 15 to 30 minute group. In the 45 to 60 minute group, tension increased
to 117.9 ± 4.8 percent (P <0.005), whereas length decreased to 86.8 ± 1.4 percent (P <0.001); and in the 2 to 3 hour group tension increased to 124.9 ± 6.0 percent (P <0.005), and length decreased to 91.9 ± 3.5 percent (P <0.001). The decrease in magnitude of responsiveness in the 45 to 60 minute and 2
to 3 hour postligation groups compared with the 15 to 30 minute postligation group
was highly significant (P <0.005). The central ischemic zone showed no significant change in tension or length
in any group. Maximal response to nitroglycerin administration in both tension and
length parameters was observed within 30 to 60 seconds and was concomitant with a
decrease in systolic pressure to 73.3 ± 1.9 percent (P <0.001) and an increase in heart rate to 107.2 ± 1.0 percent.
Nitroglycerin improves the contractile performance of the nonischemic and border zones
after coronary occlusion without affecting the central ischemic zone. However, the
border zone exhibits a progressive decrease in contractile response as a function
of time. These data suggest that nitroglycerin has the overall effect of functionally
reducing the extent of the ischemic area and strongly supports its potential clinical
usefulness in acute myocardial infarction.
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References
- Paradoxical action of glyceryl trinitrate (nitroglycerin) in coronary patients.JAMA. 1955; 158: 1017-1021
- Coronary artery occlusion in conscious dog: effects of alterations in arterial pressure produced by nitroglycerin, hemorrhage and alpha-adrenergic agonists on the degree of myocardial ischemia.Cirulation. 1973; 47: 51-57
- Evaluation of sympathetic reflex effects on the inotropic action of nitroglycerin, quinidine, papaverine, aminophylline and isoproterenol.J Pharmacol Exp Ther. 1958; 122: 386-395
- Use of sublingual nitroglycerin in congestive failure following acute myocardial infarction.Circulation. 1972; 46: 839-845
- Intravenous nitroglycerin in acute myocardial infarction.Circulation. 1973; 48 (abstr): IV-104
- Use of nitroglycerin to unmask reversibility of ventricular contraction abnormalities due to coronary disease.Clin Res. 1973; 21 (abstr): 442
- Detection of reversible contraction abnormalities with nitroglycerin: correlation with postcoronary bypass ventriculography.Circulation. 1973; 48 (abstr): IV-104
- Nitroglycerin to unmask reversible asynergy: correlation with postcoronary bypass ventriculography.Circulation. 1974; 50: 108-113
- Temporal sequence of dynamic contractile characteristics of ischemic and nonischemic myocardium following acute coronary ligation.Am J Cardiol. 1974; 34: 158-163
- Myocardial contractility in areas with chronic ischemia: studies on isometric tension.Cardiovasc Res. 1968; 3: 226-233
- Persistence of contractile behavior in acutely ischemic myocardium.Cardiovasc Res. 1969; 3: 249-260
- Direct measurement of changes in cardiac contractile force.Am J Physiol. 1956; 187: 122-134
- Hemodynamic effects of nitroglycerin, propranolol, and their combination in coronary heart disease.Circulation. 1969; 39: 623-632
- Action of nitroglycerin on coronary circulation in normal and in mild cardiac subjects.Circulation. 1959; 19: 697-704
- Myocardial energetics: basic principles and clinical implications.N Engl J Med. 1971; 285: 668-675
- Intraoperative coronary collateral function in patients with coronary occlusive disease: nitroglycerin responsiveness and angiographic correlations.Circulation. 1974; 49: 298-308
- Factors influencing measurement of contractile force of heart muscle in situ.Am J Physiol. 1950; 161: 489-504
Article info
Publication history
Accepted:
March 19,
1975
Footnotes
☆This study was supported in part by a fellowship from the American Heart Association, Southeastern Pennsylvania Chapter, Philadelphia, Pa.
Identification
Copyright
© 1975 Published by Elsevier Inc.
