Phosphorus magnetic resonance spectroscopy of the human heart: current status and clinical implications.

Magnetic resonance spectroscopy is a non-invasive technique which, by means of a spectrum, can be used to reveal the presence of certain molecules in a specific area. Magnetic resonance spectroscopy uses a strong external magnetic field and radiofrequency pulses to detect the magnetic resonance signal of nuclei which possess magnetic spin. Several biologically interesting atomic nuclei are suitable for magnetic resonance spectroscopy, such as hydrogen ('H), carbon (C), sodium (Na), and phosphorus (P). For non-invasive studies of the heart in vivo, P magnetic resonance spectroscopy has been used extensively because it provides information about the high-energy phosphate metabolism of the heart. The first cardiac P magnetic resonance spectroscopy experiments were conducted by Gadian et al. in 1976, using isolated Langendorffperfused animal hearts. In 1985 Bottomley reported the first localized human cardiac P spectra obtained in healthy volunteers. Since then, the development of P magnetic resonance spectroscopy for studies in men has grown steadily, but has been hampered by several technical difficulties. An important limitation of in vivo P magnetic resonance spectroscopy is the relatively low sensitivity of the technique resulting in long acquisition times and a low spatial resolution. Consequently, P magnetic resonance spectroscopy currently has no well-defined application in clinical cardiology. Future developments, such as the application of stronger magnetic field strengths, are expected to provide higher