Non-invasive assessment of myocardial risk and infarct area in canine model of myocardial reperfusion by intravenous contrast echocardiography

Objective To evaluate the newly developed perfluoropropene-filled echo-cont rast agent (FCT-188) in non-invasive assessment of risk areas (RA) and infa rct areas (IA) with intravenous myocardial contrast echocardiography (MCE) in canine model of ischemia followed by reperfusion. Methods Eight chest-opened Beagle dogs with a 90-minute ischemia followed b y a 240-minute reperfusion were studied. MCE was performed after a bolus in jection of FCT-188 (0. 025 ml/kg, N) into a superficial vein of the forelim b at baseline, 20 minutes after occlusion, and 4 h after reperfusion to non invasively assess the left ventricular myocardium area (LVMA), myocardial i schemic risk area (RA), and infarct area (IA) in a short-axis view of left ventricle. The accuracy of detecting myocardial perfusion with intravenous MCE was further assessed by in vitro myocardial staining of the matched cro ss-sections. Both RA and IA were expressed as percent of LVMA. Results LVMA, RA, IA, and IA/RA ratio were accurately assessed by MCE (LVMA : 6.60 cm(2) +/- 0.76 cm(2); RA: 35.7% +/- 6.68%; IA: 21.0% +/- 13.2%; IA/R A: 60.3% +/- 31.4%; n = 7) as compared with those of the matched cross-sect ion (LVMA: 6.81 cm(2) +/- 0.73 cm(2), P = 0.062; RA: 35.3% +/- 9.9%, P = 0. 84; IA: 25. 10% +/- 14.5%, P = 0.07; IA/RA: 68.0% +/- 22.2%, P = 0.28, resp ectively). There was a significant correlation of MCE-assessed IA/RA ratio and its corresponding pathologiclly determined finding in vitro (Y = 1.21 X - 21.6, r = 0.73, P = 0.015). No significant changes of electrocardiogram (ECG), mean artery pressures (MAP), pulmonary artery pressures (PAP), and p ulmonary artery wedge pressures (PAWP) were found between pre- and post-int ravenous injection of FCT-188 at each time point. Conclusion These indicate that FCT-188 can be used to assess risk areas and infarct areas accurately and non-invasively with intravenous MCE in the ca nine model of a 90-minute ischemia followed by a 240-minute reperfusion and might have potential significance for non-invasive assessment of myocardia l reperfusion clinically.