Reproducibility of human cardiac 31P-NMR spectroscopy.
The reproducibility of the phosphocreatine to adenosine triphosphate ratio (PCr/ATP) was assessed from cardiac phosphorus-31 (31P) NMR spectra of the human left ventricle acquired with three different localization techniques. Cardiac 31P-NMR spectra (n = 68) were obtained at rest from 16 healthy subjects with three-dimensional (3D) image selected in vivo spectroscopy (ISIS), 1D spectroscopic imaging (SI), or with a combination of 2D ISIS and the 1D SI technique (ISIS + SI). The average PCr/ATP ratios were 1.41 +/- 0.20 for ISIS + SI and 1.31 +/- 0.19 for ISIS and were in the lower range of values obtained in previous studies, mainly because of a lower saturation correction factor for the cardiac PCr/ATP ratio. The SI experiment yielded an average PCr/ATP value of 0.98 +/- 0.20, significantly lower as compared to the correct values obtained with ISIS + SI and ISIS (p < 0.001), underscoring the need for 3D localization to avoid contamination of the NMR signal by liver tissue. Intersubject standard deviations of the PCr/ATP ratio were comparable to values reported previously. For all three localization techniques the absolute intra-examination differences in PCr/ATP (0.06 for ISIS to 0.15 for ISIS + SI) were significantly smaller (p approximately 0.03) than inter-examination differences (0.24 for ISIS to 0.29 for ISIS + SI). Therefore, consecutive acquisition of cardiac 31P-NMR spectra from the same patient during a single examination, e.g. under various cardiac loading conditions, appears to be a reliable approach for metabolic evaluation of heart disease.
Lamb
H J
HJ
Department of Diagnostic Radiology and Nuclear Medicine, Leiden University Medical Centre, The Netherlands.
Doornbos
J
J
den Hollander
J A
JA
Luyten
P R
PR
Beyerbacht
H P
HP
van der Wall
E E
EE
de Roos
A
A
D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D005260:Female; D006801:Humans; D007206:Individuality; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D010725:Phosphocreatine / Q000378:metabolism; D010758:Phosphorus; D015203:Reproducibility of Results; D012737:Sex Factors; D016277:Ventricular Function, Left / Q000502:physiology
D010725:Phosphocreatine; D010758:Phosphorus; D000255:Adenosine Triphosphate