Effects of perfluorocarbon exchange transfusion on reducing myocardial infarct size in a primate model of ischemia-reperfusion injury: a prospective, randomized study.

Background . This study was undertaken to test the hypothesis that perfluorocarbons were able to reduce myocardial infarct size in a baboon model of ischemia-reperfusion injury. Exchange transfusion of perfluorocarbons has been shown to reduce myocardial infarct size in the dog, who, unlike the baboon, has an extensive collateral circulation. Methods . After 15 minutes of occlusion of the left anterior descending coronary artery, 14 baboons were bled to attain a hematocrit of 24% to 26% and were simultaneously transfused, six with Flusol-DA 20% emulsion and eight with FC-43 emulsion. After 2 hours of ligation, the coronary arteries were reperfused. Baboons were killed 24 hours after ligation, and the hearts were excised. Microvascular dye was infused into the coronary artery to delineate its perfusion bed. Ratios of the mean volume of infarct to the mean volume of perfusion bed were calculated and compared by use of planimetry. A similar protocol was followed in two other groups of baboons except that lactated Ringer's solution was infused into six of them, whereas eight had no exchange transfusions. Results. The ratios of the mean volume of infarct to the mean volume of perfusion bed of the four groups were as follows: Fluosol-DA, 38.1%±7.5%; FC-43, 37.7%±8.3%; lactated Ringer's, 46.9%±10.5%; controls, 65.6%±6.9%. Statistical significance was reached when comparing both perfluorocarbon-treated groups with the controls (p Conclusions. Results suggest that the beneficial effects of exchange transfusion with the perfluorocarbons may be primarily due to hemodilution.