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 (A_R); 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 (a_n). The ratio of $\text{A}{}_{\mathrm{N}}\text{A}{}_{\mathrm{R}}$ and total left ventricular mass were then compared with the use of planimetry.The results were as follows: the $\text{A}{}_{\mathrm{N}}\text{A}{}_{\mathrm{R}}$ 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 < 0.01 compared with control; p < 0.001 compared with the saline group).Fluocarbon exchange transfusion may reduce infarct size when administered after coronary occlusion.