Evaluation of myocardial viability with contrast echocardiography
Identification of viable myocardium after acute myocardial infarction (MI) or in the setting of severe chronic ischemic heart disease has important clinical implications. Myocardial contrast echocardiography (MCE) has been used for the evaluation of myocardial viability by assessing myocardial perfusion and microvascular integrity. In acute MI, MCE can identify the no-reflow phenomenon after revascularization, which has significant implications regarding recovery of function and clinical outcomes. Serial changes in myocardial perfusion can also be evaluated for the prediction of ultimate recovery of function. In the setting of chronic ischemic left ventricular dysfunction, early studies have shown that MCE is helpful in the identification of myocardial hibernation and in the prediction of recovery of function after revascularization, with accuracy similar to radionuclide techniques. Preliminary studies using the new quantitative MCE parameters of myocardial blood flow and velocity derived from intravenous contrast administration appear to enhance the diagnostic accuracy of MCE in the evaluation of myocardial viability.