CLINICAL-SIGNIFICANCE AND ECHOCARDIOGRAPHIC ASSESSMENT OF MYOCARDIAL VIABILITY IN CHRONIC ISCHEMIC CARDIOMYOPATHY

It is now clear that a significant proportion of dysfunctional myocard ial segments in patients with chronic ischemic cardiomyopathy is compr ised of viable tissue with a potential for functional recovery. The co ntractile dysfunction in these viable myocardial segments results from prolonged resting hypoperfusion (hibernating myocardium) or acute sev ere ischemia-reperfusion (stunned myocardium), The presence of viabili ty in asynergic myocardium can be detected by evaluating regional perf usion, metabolism or contractile reserve. Coronary revascularization c an improve the outcome for patients with chronic ischemic cardiomyopat hy in whom large areas of viable myocardium are detected. Dobutamine s tress echocardiography has been found to be an accurate method of dete cting viable myocardium in ischemic cardiomyopathy. Also, recent devel opments in myocardial contrast echocardiography can potentially improv e the use of echocardiography in the evaluation of myocardial viabilit y. This manuscript summarizes the general concepts, pathology, and ech ocardiographic assessment of viable myocardium in chronic ischemic car diomyopathy.