Myocardial viability: unresolved issues.

The determination or assessment of myocardial viability has, over the past decade, captured the imagination and interest of many investigators in basic and clinical research using state-of-the-art technologies such as PET, SPECT, MRI and two-dimensional echocardiography (2-DE). The emphasis in these studies has been to determine the absolute and comparative accuracy of these techniques. There are recent studies addressing the evaluation of the effect of viability assessment on patient outcome. The use of biochemical agents and other imaging methods in viability assessment is complex with many unresolved issues to be considered in the design and implementation of clinical protocols and in routine patient care.