Myocardial contrast echocardiography in coronary artery disease.

Myocardial contrast echocardiography (MCE) allows the assessment of myocardial perfusion by imaging the coronary microcirculation. The development of new contrast agents and new diagnostic tools far assessing myocardial perfusion by means of MCE has led to a new field of applications far patients suffering from ischemic heart disease. Several studies have shown that MCE is a feasible and accurate method to evaluate patients with: a) acute coronary syndromes: MCE is useful before the epicardial reperfusion to delineate the area at risk and to assess the collateral-derived myocardial blood flow, and after the epicardial reperfusion to detect the non-reflow phenomenon; b) chronic coronary syndromes: MCE allows the detection of significant coronary stenosis by means of stress methods and methods without any stress; c) myocardial viability and hibernating myocardium: MCE helps to predict functional recovery of akinetic segments. In these settings, MCE is not only useful as a diagnostic tool but also provides prognostic information. MCE is a technique in constant development. Among the latest advances we note the development of transesophageal probes with second-harmonic image that allows assessment of myocardial perfusion in a more accurate way. This technique should introduce MCE into new clinical fields, especially the evaluation of myocardial perfusion during cardiac operations. Another recent development is in parametric imaging techniques. These consist in obtaining time curves for all the pixels in the image instead of working only with a few separate regions of interest. A parameter scan is computed far any pixel showing their value as a color overlay in the parametric image. Summarizing, we can say that MCE is crossing from the experimental laboratory to the daily clinical practice far the evaluation of ischemic heart disease. MCE provides an interesting tool that offers the potential of a complete evaluation of patients with chronic coronary artery disease. This includes both diagnostic and prognostic evaluation.