Verification of myocardial contrast two-dimensional echocardiographic assessment of perfusion defects in ischemic myocardium

Abstract

Myocardial contrast two-dimensional echocardiography was used in 21 closed chest dogs to assess its ability to delineate the extent of underperfused acutely ischemic myocardium. An agitated saline-Renografin echocardiographic contrast agent was injected into the left main coronary artery after left anterior descending coronary artery occlusion, and the size of the contrast echo-free area characterizing the perfusion defect was outlined in short-axis cross sections of the left ventricle. In 13 dogs, monastral blue dye was injected after 45 minutes of coronary artery occlusion and before sacrifice to provide anatomic delineation of underperfused zones in equivalent sections. Perfusion defects assessed by contrast two-dimensional echocardiography correlated well with those delineated by monastral blue dye (r = 0.91). Contrast echocardiographic study was also performed in eight other dogs at 5 hours of occlusion, after which infarct size was measured with triphenyl-tetrazolium-chloride. Contrast echocardiographic outline of the perfusion deficiency correlated but slightly overestimated the extent of necrosis (r = 0.88). It is concluded that contrast two-dimensional echocardiography can detect and outline the underperfused "risk area" during acute coronary artery occlusion, and may also permit assessment of the extent of myocardial infarction.