Computed tomographic analysis of the effects of hyperosmolar mannitol and methylprednisolone on myocardial infarct size.
Using contrast-enhanced computed tomography, the effects of hyperosmolar mannitol and methylprednisolone on experimentally produced myocardial infarcts were evaluated serially over the course of approximately 1 month. Infarct size, initial perfusion defect (jeopardized segment) and noninfarcted muscle mass were determined in three groups of conditioned mongrel dogs. Group 1 (n = 11) served as the control group, groups 2 and 3 were pretreated with mannitol (375 mg/kg, n = 10) or methylprednisolone (7.5 mg/kg, n = 11). Each animal in the treatment groups was treated with identical doses of the originally administered agent twice daily for 7 days after coronary occlusion. Each group developed increases in the noninfarcted muscle mass of the left ventricle (compensatory hypertrophy). The mean increase averaged more than 20% over 30 days when all groups were included together. Infarct size was smaller in both of the treatment groups. However, at 4 days after infarction, mannitol-treated dogs had a mean infarct size that was 68 +/- 8% (+/- standard error of the mean) of the size of control infarcts (p less than 0.01) and methylprednisolone-treated dogs had a mean infarct size that was 77 +/- 6% of the size of control infarcts (p less than 0.01) (referenced to the initial perfusion defect). At 30 days, these differences were less substantial (though still significant), 88 +/- 4% and 85 +/- 5%, respectively. Pharmacologic interventions can be shown to alter the size of an acute myocardial infarction, particularly when examined over the time course of infarct healing.(ABSTRACT TRUNCATED AT 250 WORDS)
Slutsky
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RA
Murray
M
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D000818:Animals; D006332:Cardiomegaly / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D006439:Hemodynamics / Q000187:drug effects; D008353:Mannitol / Q000494:pharmacology* / Q000627:therapeutic use; D008775:Methylprednisolone / Q000031:analogs & derivatives*; D008776:Methylprednisolone Hemisuccinate / Q000494:pharmacology* / Q000627:therapeutic use; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology*; D009994:Osmolar Concentration; D010477:Perfusion; D013997:Time Factors; D014057:Tomography, X-Ray Computed
D008353:Mannitol; D008776:Methylprednisolone Hemisuccinate; D008775:Methylprednisolone