New echocardiographic technologies in the study of acute myocardial infarction

Echocardiography has a key role in the diagnostic and prognostic evaluation of patients in the different phases of acute myocardial infarction. Despite this important role of the conventional echocardiographic technologies, novel echocardiographic applications are under development or already used in the clinical practice. It is very difficult to distinguish which of these techniques will play a consistent role and will cover important diagnostic, prognostic and therapeutic use. The wise cardiologist will be the one who will choose the appropriate technology for the right subset of patients. In this review paper we try to assign to each novel echocardiographic technique its actual clinical weight in every pathophysiological condition: myocardial contrast echocardiography, contrast opacification of the left ventricle, coronary flow reserve study, integrated backscatter, tissue Doppler and strain rate imaging. For the best treatment choice, each patient has to be perfectly diagnosed and characterized in order to have a tailored therapy. A correct diagnosis of the extension of myocardial necrosis cannot ignore the transmural wavefront development, the amount of viable myocardium or the presence of microvascular damage. Also the simple echocardiographic wall motion akinesia can be caused by a variable extension of non-contracting, scarred myocardium. The different anatomic and functional intramyocardial patterns represent the basis for different functional outcome of regional and hence global left ventricular function. The greatest understanding of the pathology always leads to the best treatment.