title: The effects of chronic oral milrinone therapy on early postinfarction left ventricular remodeling.
abstract: Left ventricular remodeling following acute transmural myocardial infarction may result in early left ventricular enlargement. To characterize the effects of milrinone on components of early left ventricular dilation, rats (n = 120) underwent left coronary artery ligation or sham surgery. In the immediate postoperative period, rats received either no treatment or milrinone (3.17 +/- 0.08 mg/kg/day) dissolved in drinking water for 20 days. Twenty-one days after the initial surgery, hemodynamic measurements were made. The rats were then put to death and the hearts arrested in diastole were excised and fixed at a constant pressure for morphometric analysis. To examine the effects of milrinone on the relative contribution of infarcted and noninfarcted segments to early left ventricular dilation after acute myocardial infarction, a subgroup of infarcted rats chosen randomly was put to death 3 days after the initial surgery for morphometric analysis. Compared with infarcted untreated rats, infarcted milrinone-treated rats had a lower left ventricular volume (1.41 +/- 0.07 ml/kg vs 2.16 +/- 0.19 ml/kg, p < 0.001), lower left ventricular wall stress (0.64 +/- 0.03 vs 0.91 +/- 0.06, p < 0.001), and a lower expansion index (1.61 +/- 0.12 vs 2.61 +/- 0.22, p < 0.001). Morphometric analysis revealed that the noninfarcted segment length did not differ between the two infarcted groups either 3 days or 21 days after left coronary artery ligation. Infarct segment length also did not differ between the two infarcted groups at 3 days, but at 21 days infarct segment was shorter in the milrinone-treated group compared with the untreated group (p < 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Medicine, State University of New York, Stony Brook 11794-8171.
authors.forename: P
authors.initials: P
authors.lastname: Jain
authors.forename: M
authors.initials: M
authors.lastname: Hughes
authors.forename: G
authors.initials: G
authors.lastname: Korlipara
authors.forename: O
authors.initials: O
authors.lastname: Lillis
authors.forename: J P
authors.initials: JP
authors.lastname: Dervan
authors.forename: P F
authors.initials: PF
authors.lastname: Cohn
mesh_terms: D000284:Administration, Oral; D000704:Analysis of Variance; D000818:Animals; D002316:Cardiotonic Agents / Q000008:administration & dosage*; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D005260:Female; D006321:Heart / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D017379:Hypertrophy, Left Ventricular / Q000188:drug therapy* / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology; D020105:Milrinone; D009203:Myocardial Infarction / Q000150:complications / Q000188:drug therapy* / Q000453:epidemiology / Q000503:physiopathology; D009206:Myocardium / Q000473:pathology; D011728:Pyridones / Q000008:administration & dosage*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
chemical_list: D002316:Cardiotonic Agents; D011728:Pyridones; D020105:Milrinone