Ultrasonic enhancement of myocardial infarction with perfluorocarbon compounds in dogs.

Fluosol-DA 20% (Fluosol) and perfluoroctylbromide (PFOB), 2 types of perfluorocarbon emulsions (PFCs), were evaluated as sound contrast agents in imaging acute myocardial infarction (MI) in dogs. Operative ligation of a coronary artery was performed in 9 dogs. PFC was administered 2 days after occlusion. One dog received Fluosol, 10 ml/kg body weight, 2 dogs received 20 ml/kg, and 2 received 25 ml/kg; 2 dogs received PFOB, 20 ml/kg, and 2 dogs received 25 ml/kg. Just before and 2 days after PFC administration, real-time, 2-dimensional ultrasound examination of the heart was performed in the short-axis view from apex to base. No enhancement was seen at the 10-ml/kg dose, but significant mild echogenic enhancement of all MIs occurred after 20 ml/kg. Moderate to marked enhancement was noted after 25 ml/kg. The enhancement was either diffuse throughout the MI or localized to the rim. Initial studies suggest that the mechanism of enhancement is related, at least in part, to the accumulation of PFC-filled macrophages within the MI.