Assessment of myocardial viability and the role of surgery

The importance of accurately predicting functional recovery of the myocardium has become clear with the advent of interventional techniques for coronary revascularization. Detection of hibernating myocardium (reversibly dysfunctional myocardial segments subtended by stenosed arteries) has been approached by techniques that assess different characteristics of this condition, such as contractile reserve, membrane integrity, and metabolic activity. The standard for detecting viable myocardium is considered to be metabolic imaging with positron-emission tomography using the glucose analogue 18F-fluorodeoxyglucose, which makes it possible to quantitate regional glucose utilization in myocardium. However, recently, a new approach has been proposed based on the use of 15O-labeled water, which does not require metabolic imaging and appears to offer advantages in terms of scanning time and quantitation of viable tissue.