title: Regional myocardial blood flow in experimental myocardial infarction after pretreatment with aspirin.
abstract: The effects of aspirin on myocardial blood flow in an area of ischemia were studied in 12 baboons. In each, a diagonal branch of the left anterior descending coronary artery was ligated. Six of the baboons received aspirin (2 X 600 mg orally, 12 hours and 1 hour before ligation); the other six did not receive aspirin and served as a control group. The extent of myocardial ischemia was delineated with an electrode wire grid on the surface of the anterior left ventricular wall. The maximal area circumscribed by electrodes with 2 mV or more ST segment elevation was compared with the area of reduced myocardial blood flow. Myocardial blood flow was measured with the radioactive microspheres method using strontium-85-labeled carbonized spheres. Two areas of reduced myocardial blood flow were noted, one with severely reduced flow in the center of the myocardial infarct (0 to 49% of noninfarcted myocardium) and another with mild to moderately reduced myocardial blood flow at the border of the myocardial infarct (50 to 90% of noninfarcted myocardium). Myocardial blood flow in the border area (margins of ST elevation area) for the total wall was 85 +/- 8% of normal in the aspirin-treated animals and 40 +/- 4% in the control group (p less than 0.01); for the epicardium it was 67 +/- 10% of normal in noninfarcted myocardium after aspirin and 37 +/- 5% for the control group (p less than 0.05); and for the endocardium it was 78 +/- 8% of normal in noninfarcted myocardium after aspirin and 39 +/- 6% in the control group (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D001241:Aspirin / Q000494:pharmacology* / Q000627:therapeutic use; D003326:Coronary Circulation / Q000187:drug effects*; D004562:Electrocardiography; D006321:Heart / Q000502:physiology; D009203:Myocardial Infarction / Q000188:drug therapy*; D010215:Papio
chemical_list: D001241:Aspirin