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Updated: Jul 23, 2026
14:19
Primary Outcome Assessment in a Pig Model of Acute Myocardial Infarction
Published on: October 14, 2016
Correlation between divalent cation concentration and electrocardiogram in canine myocardial infarction
Journal of Electrocardiology
|October 1, 1983
Summary
Myocardial infarction in dogs caused serum magnesium and zinc levels to drop, coinciding with heart rhythm disturbances. Copper levels rose, but without apparent effect on cardiac electrical activity.
Area of Science:
- Cardiology
- Biochemistry
- Electrophysiology
Background:
- Myocardial infarction (MI) alters serum divalent cation concentrations.
- The impact of these ionic shifts on cardiac electrical activity remains incompletely understood.
Purpose of the Study:
- To investigate the relationship between serum divalent cation changes and cardiac electrical activity following myocardial infarction.
- To determine the specific effects of magnesium, zinc, copper, and calcium level alterations on the heart's electrical function post-MI.
Main Methods:
- Mongrel dogs underwent coronary artery catheterization and occlusion or sham procedures.
- Serum concentrations of magnesium ([Mg++]), zinc ([Zn++]), copper ([Cu++]), and calcium ([Ca++]) were measured at intervals up to 72 hours post-surgery.
- Electrocardiograms (ECGs) were continuously monitored to assess cardiac electrical activity, including ST segment changes and arrhythmias.
Main Results:
- Coronary artery occlusion led to significant ST segment changes in lead V4.
- Serum [Mg++] and [Zn++] decreased by approximately 20% at 24 hours post-occlusion, correlating with prevalent ventricular tachycardia and premature beats.
- Serum [Cu++] increased by approximately 30% at 48 and 72 hours in both occluded and non-occluded dogs, with no observed effect on cardiac electrical activity.
- Serum [Ca++] remained unchanged throughout the study.
Conclusions:
- Decreases in serum magnesium and zinc levels are associated with cardiac dysrhythmias during myocardial ischemia.
- Elevations in serum copper are not specifically linked to myocardial ischemia and do not appear to affect cardiac electrical activity within physiological limits.
- Serum calcium levels do not exhibit significant changes in this model of myocardial infarction.
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