Is electrical mapping for myocardial viability superior to conventional methods?
At present, conventional methods for assessing myocardial viability including radionuclide techniques,27,28low-dose dobutamine echocardiography,29and contrast enhanced magnetic resonance imaging30are superior to direct epicardial mapping because they all are non-invasive. There is consensus that only radionuclide techniques such as 18F-FDG-PET represent the gold standard for detection of myocardial viability.2718F-FDG-PET identified viability in a relatively high percentage of segments with even less than 25% of viable myocardium.31Therefore, the specificity of 18F-FDG-PET in predicting the recovery of LV dysfunction is limited, while the sensitivity is high. In contrast, in hypokinetic regions, elicitation of a contractile response by dobutamine stimulation requires at least 50% of the myocytes within a segment to be viable.31Therefore, low-dose dobutamine echocardiography shows the highest specificity32and the best accuracy of a positive test33in predicting recovery of myocardial con
