We hypothesized that simultaneous assessment of myocardial perfusion and a regional wall motion abnormality, using real-time myocardial contrast echocardiography (MCE), provides more useful information than routine two-dimensional echocardiography (2DE) in the diagnosis of acute coronary syndrome in patients with a non-diagnostic ECG.

We prospectively enrolled 101 patients (age:61±10 years, 57 men) who presented with acute chest pain. A routine 2DE was performed to evaluate the regional wall motion abnormality, and a MCE to assess the perfusion defect. Coronary angiography was performed in all patients. The cardiac events (myocardial infarction, revascularization and death) were analyzed.

Of the 101 patients studied, 64 had significant coronary artery disease (diameter stenosis >0%). Cardiac events occurred in 58 patients;21 myocardial infarction, 48 revascularization. The sensitivities of 2DE and MCE for significant coronary artery stenosis were 57.8 and 73.4%, and the specificities were 83.8 and 81.1%, respectively. Of the 58 patients with cardiac events, a regional wall motion abnormality was observed in 34 (59%), and a perfusion defect in 44 (76%). The specificities of 2DE and MCE for cardiac events were 79 and 77%, respectively. Cardiac events were more frequent in males, smokers and in those with an abnormal ECG (p<.05), but only a perfusion defect independently predicted cardiac events (p<.001, odds ratio=8.37).

Real time MCE, in patients with acute chest pain, reasonably predicts significant coronary artery stenosis, and identifies those who will have cardiac events.