Effect of fluocarbon exchange transfusion on myocardial infarction size in dogs

Fluosol DA (20%), a perfluocarbon with high oxygen solubility, was administered by concurrent exchange transfusion (30 ml/kg) to anesthetized open-chested adult greyhounds (n = 9) 1 hour after left anterior descending coronary ligation. Mechanical ventilation using 100% oxygen was used throughout the experiment. A second similar group (n = 9) received 0.9% normal saline solution (30 ml/kg), and a third group (n = 9) received no further intervention. Systemic, right atrial, and left atrial pressures were not altered by the exchange transfusion. Monastryl blue dye was injected through the left atrial line at 6 hours after ligation to define the area of myocardium at risk (AR); the animals were then killed and the heart was excised. The left ventricle was sliced at 5 mm intervals and stained using triphenyltetrazolium chloride, defining areas of necrosis (AN). The ratio of AN/AR and total left ventricular mass were then compared with the use of planimetry. The results were as follows: the AN/AR ratio in the 9 control animals was 90 +/- 2 (mean +/- standard error of the mean); in the 9 animals who received saline solution it was 88 +/- 2; and in the animals who received Fluosol it was 67 +/- 4 (p less than 0.01 compared with control; p less than 0.001 compared with the saline group). Fluocarbon exchange transfusion may reduce infarct size when administered after coronary occlusion.