Although echocardiography has a well established role in the evaluation of patients with coronary artery disease, in many cases it does not provide appropriate information regarding the processes underlying ventricular wall motion abnormalities. In conditions like acute ischaemia, stunning, hibernation, infarction, and the no reflow phenomenon, improved diagnostic information might be derived from myocardial perfusion data. In recent years, satisfactory results at the identification of myocardial perfusion abnormalities have been achieved using hand agitated or sonicated radiographic contrast agents directly injected into the coronary arteries during cardiac catheterisation.1-12 Subsequently, it became apparent that accurate and reproducible myocardial enhancements were attainable by peripheral venous injection of second generation contrast agents13-17 and harmonic intermittent imaging,18-22 whose sensitivity in detecting microbubbles was further increased by the introduction of power Doppler.23 ,24 This non-invasive, non-nuclear approach to the study of myocardial perfusion has expanded the interest of cardiologists in myocardial contrast echocardiography.

The capability of contrast echocardiography to recognise the presence of viable myocardium is based on the assumption that preserved microvascular integrity, as seen by intracoronary contrast administration, is a necessary prerequisite of viability in patients with recent or remote myocardial infarction.4-6 However, there is some debate over the recognition of viable tissue from the perfusion data. In the studies in which the recovery of myocardial function was considered as the gold standard of viability, some discrepancies were noted concerning the reliability of contrast echocardiography in predicting regional recovery. In patients who suffered from an acute myocardial infarction, the specificity of the technique in recognising viable tissue was only 18% early after the onset of symptoms,9 but was 57–67% in the chronic phase.10 ,11 Another controversy concerned the conflicting results obtained in the prediction of recovery of global versus regional left ventricular function based …