Magnetic resonance spectroscopy in myocardial disease.

31-phosphorous ((31)P) magnetic resonance spectroscopy (MRS) is a technique that allows the noninvasive characterization of the biochemical and metabolic state of the myocardium in vivo. MRS is a pure form of molecular imaging using magnetic resonance signals from nuclei with nuclear spin to assess cardiac metabolism without the need for external radioactive tracers. (31)P MRS provides information on the underlying metabolic abnormalities that are fundamental to common conditions including ischemic heart disease, cardiomyopathy, hypertrophy and valvular disease. (31)P MRS could potentially also have a role to play in assessing response to therapy as well as the effectiveness of metabolic modulating agents. However, the use of MRS is currently limited to research due to its poor reproducibility, low spatial and temporal resolution, and long acquisition times. With technical advances in both the spectrometers and postprocessing, MRS is likely to play a role in the future of multimodal noninvasive cardiac assessment.