Magnetic resonance techniques for assessment of myocardial viability

In general, the following three standards for myocardial viability can be used: (a) preserved coronary flow (adequate perfusion); (b) preserved wall motion (systolic wall thickening); and (c) preserved metabolism (metabolic integrity). The current magnetic resonance (MR) techniques provide a great potential to measure all three standards of viability. Adequate perfusion can be assessed by spin-echo MR imaging and/or ultrafast MR imaging, systolic wall thickening by cine MR imaging, and the presence of metabolic integrity can be determined by MR spectroscopy. These noninvasive and versatile techniques have led to an increasing interest and research in recent years. Particular strengths of the MR techniques are: the inherent three-dimensional data acquisition without radiation exposure; the intrinsic soft-tissue contrast that allows tissue characterization; the excellent spatial resolution (in the 1- to 2-mm range), which permits the evaluation of regional abnormalities; multitomographic imaging capabilities that allow acquisition of cardiac images in any plane; the inherent sensitivity to blood and wall motion; and the potential for in vivo measurement of myocardial metabolism using MR spectroscopy. This review article demonstrates that MR techniques might play a growing role in the assessment of myocardial viability.