title: Evaluation of nonradioactive, colored microspheres for measurement of regional myocardial blood flow in dogs.
abstract: Measurement of regional myocardial blood flow (RMBF) is crucial in experimental studies of myocardial ischemia and reperfusion in dogs. The standard measurement technique uses radioactive microspheres; however, not all institutions are able to dispose of radioactive waste and therefore cannot make use of this method. We tested a new, nonradioactive microsphere, labeled with colors instead of nuclides. Simultaneous blood flow measurements with two nuclide-labeled and two colored microspheres were performed after coronary occlusion in dogs. Both techniques show a within-method correlation of r greater than 0.98. Duplicate variability for paired RMBF values in 80 samples was 8.7 +/- 0.1% when computed with radioactive microspheres and 13.2 +/- 1.8% when computed with colored microspheres. There was a good correlation in the measurement of RMBF between the radioactive- and colored-microsphere methods (r = 0.98). The best-fitting linear regression line was expressed by the formula: Colored-microsphere RMBF = 1.11 (radioactive-microsphere RMBF)-0.02. When measured by colored microspheres, RMBF was approximately 8% higher than when computed with radioactive microspheres for blood flow values of 0-2 ml/min/g. When blood flow was increased pharmacologically to levels of 2-7.5 ml/min/g, colored microspheres yielded blood flow values 39% higher than the values computed by radioactive microspheres. We conclude that the nonradioactive, colored-microsphere method correlates with the radioactive technique, but at high flows, it yields values greater than those obtained with radioactive microspheres.
authors.affiliation: Department of Medicine, Wayne State University School of Medicine, Detroit, Michigan.
authors.forename: S L
authors.initials: SL
authors.lastname: Hale
authors.forename: K J
authors.initials: KJ
authors.lastname: Alker
authors.forename: R A
authors.initials: RA
authors.lastname: Kloner
mesh_terms: D000818:Animals; D002565:Cerium Radioisotopes; D003116:Color; D003326:Coronary Circulation; D003327:Coronary Disease / Q000503:physiopathology; D004285:Dogs; D005260:Female; D006339:Heart Rate; D008297:Male; D008863:Microspheres; D009556:Niobium; D011868:Radioisotopes; D012429:Ruthenium Radioisotopes
chemical_list: D002565:Cerium Radioisotopes; D011868:Radioisotopes; D012429:Ruthenium Radioisotopes; D009556:Niobium