Accuracy of dipyridarnole myocardial contrast echo cardiography for the detection of residual stenosis of the infarct-related artery and multivessel disease early after acute myocardial infarction

OBJECTIVES We aimed to evaluate the ability of vasodilator myocardial contrast echocardiography (MCE) to detect significant infarct-related artery (IRA) stenosis and multivessel disease (MVD) after thrombolysis. BACKGROUND The detection of residual IRA stenosis subtending significant viable myocardium and the identification of MVD may help to triage patients who may benefit from mechanical revascularization after acute myocardial infarction (AMI) and thrombolysis. METHODS Patients with AMI under-went low-power MCE at rest and after dipyridamole stress during SonoVue infusion seven to 10 days after thrombolysis. RESULTS Of the 73 patients, 61 demonstrated significant myocardial viability, of whom 57 (93%) showed significant IRA stenosis. Sensitivities to detect >50% IRA stenosis and MVD were 88% and 72%, respectively. The accuracy of detecting significant coronary stenosis in the anterior (left anterior descending coronary artery) versus inferoposterior (right coronary artery/left circumflex artery) circulation was similar for both IRA (85% vs. 91%) and remote territories (91% vs. 81%). Quantitative peak contrast intensity (p = 0.02), microbubble velocity (p = 0.0001), and myocardial blood flow (p < 0.0001) were significantly lower in patients with significant coronary stenosis during dipyridamole compared with rest. Only beta reserve discriminated various grades of coronary stenosis. CONCLUSIONS Use of MCE accurately predicted significant M stenosis and MVD after thrombolysis. This information is valuable for identifying patients who may benefit from mechanical revascularization. (C) 2004 by the American College of Cardiology Foundation.