Assessment of myocardial viability in patients with postischemic left ventricular dysfunction: role of myocardial contrast echocardiography.

The distinction between viable and nonviable dysfunctional left ventricular (LV) segments after acute myocardial infarction is very important, because revascularization increases survival only in patients with viable myocardial tissue. Recent studies have highlighted a mismatch between two highly specific investigations for viability assessment: dobutamine echocardiography, which measures inotropic reserve, and myocardial contrast echocardiography (MCE), which measures microvascular perfusion. Viability and functional reserve are not synonymous.