Risk area determination using myocardial contrast echocardiography

In summary, RA is the region of the myocardium that is at risk of necrosis following acute coronary occlusion, and should be differentiated from the anatomic perfusion bed of a coronary artery. The size of the RA is influenced by several factors. The RA is the most important determinant of the ultimate infarct size. When hemodynamic conditions do not change, the size of the RA remains constant for 48 hours following acute coronary occlusion. The endocardial extent of the RA predicts the endocardial extent of the infarct. During occlusion without reperfusion, the RA always appears to be transmural and does not predict the transmural extent of the infarct; however, following reperfusion, the RA might predict the transmural extent of the infarct as well. The size of the RA is poorly reflected by hemodynamic variables measured during acute infarction. Although the extent of abnormal wall motion is also directly related to the size of the RA, the relationship is influenced by the analytical methods employed to assess wall motion. Furthermore, wall motion abnormalities might be present even in areas not supplied by occluded vessels (prior infarction, stunned myocardium, hypoperfusion), making it a difficult parameter to use for assessing the size of the RA. MCE is a clinically applicable technique that has been shown to reliably measure RA in vivo. It has the unique capability of serially and easily measuring RA in real time. MCE should be seriously considered for replacing other post-mortem techniques for measuring RA in the experimental setting. MCE also has the potential for measuring RA in the clinical situation, and may have an important future in this era of interventional cardiology.