[Myocardial contrast echocardiography with harmonic power Doppler and lung traversing SHU 563A ultrasound contrast medium for imaging myocardial perfusion disorders].

The current approach for the assessment of myocardial perfusion using contrast echocardiography involves black-and-white gray scale imaging in b-mode. For better appreciation of perfusion abnormalities, off-line postprocessing techniques including color encoding are used. In this study, we examined whether we could exploit the contrast microbubble response to high ultrasound amplitude--the phenomenon of stimulated acoustic emission--that could be recorded with harmonic power Doppler (HPD) in color to identify myocardial perfusion defects. To assess the potential of HPD, we occluded branches of the left coronary artery for 2-3 h followed by 1 h reperfusion in 10 dogs. After transvenous administration of the new air-filled contrast agent SHU 563A, echocardiographic imaging was performed with ECG-triggered harmonic b-mode (HBM) and the harmonic power Doppler (HPD) approach in different short (SAX) and long axis (LAX) views. Post-mortem TTC staining was performed to verify infarction. HBM, HPD and TTC data were analyzed by independent observers. During coronary occlusion, HPD with SHU 563A showed perfusion defects in 10 dogs in all SAX and LAX views. HBM demonstrated perfusion defects in all dogs in SAX and in 8 dogs in LAX. The correlation of perfusion defect size between HPD and HBM images was good (SAX: r = 0.9, p < 0.001, LAX: r = 0.7, p < 0.01). One hour after reperfusion, both HPD and HBM showed perfusion defects with SHU 563A in 7 dogs. Five dogs showed TTC evidence of infarction. Perfusion defect size by HPD correlated well with residual infarct size (r = 0.8, p < 0.01), while defect size by HBM showed poor correlation (r = 0.3, p = ns). Myocardial contrast echocardiography with HPD and contrast agent SHU 563A identifies perfusion defects in acute coronary occlusion as reliably as HBM. After reperfusion HPD and SHU 563A accurately portray the site and size of residual myocardial infarction on line, in color. This approach has excellent potential for clinical application.