Feasibility of rapid-sequence 31P magnetic resonance spectroscopy in cardiac patients.
OBJECTIVE
To determine the clinical feasibility of rapid-sequence phosphorus-31 magnetic resonance spectroscopy (31P-MRS) of the heart with cardiac patients using a 1.5T clinical MR system.


METHODS
Twenty cardiac patients, i.e. dilated cardiomyopathy (DCM) 13 cases, hypertrophic cardiomyopathy (HCM) 3 cases, hypertensive heart diseases (HHD) 3 cases, and aortic regurgitation (AR) 1 case were examined using rapid cardiac 31P-MRS. Complete three-dimensional localization was performed using a two-dimensional phosphorus chemical-shift imaging sequence in combination with 30-mm axial slice-selective excitation. The rapid-sequence 31P-MRS procedure was phase encoded in arrays of 8 x 8 steps with an average of 4 acquisitions. The total examination time, including proton imaging and shimming, for the rapid cardiac 31P-MRS procedure, ranged from 10 to 15 min, depending on the heart rate. Student's t test was used to compare creatine phosphate (PCr)/adenosine triphosphate (ATP) ratios from the cardiac patients with those of the control subjects (n = 13).


RESULTS
The myocardial PCr/ATP ratio obtained by rapid 31P-MRS was significantly lower (P < 0.001) in DCM patients (1.82 +/- 0.33, mean +/- SD), and in patients with global myocardial dysfunction (combined data for 20 patients: 1.89 +/- 0.32) than in normal volunteers (2.96 +/- 0.59). These results are similar to previous studies.


CONCLUSIONS
Rapid-sequence 31P-MRS may be a valid diagnostic tool for patients with cardiac disease.
Chida
K
K
Department of Radiological Technology, School of Health Sciences, Faculty of Medicine, Tohoku University, Sendai, Japan. chida@rad.cms.tohoku.ac.jp
Otani
H
H
Saito
H
H
Nagasaka
T
T
Kagaya
Y
Y
Kohzuki
M
M
Zuguchi
M
M
Shirato
K
K
D000255:Adenosine Triphosphate / Q000032:analysis / Q000378:metabolism; D003935:Diagnostic Techniques, Cardiovascular; D004562:Electrocardiography / Q000379:methods; D005240:Feasibility Studies; D005260:Female; D006331:Heart Diseases / Q000175:diagnosis* / Q000378:metabolism; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D010725:Phosphocreatine / Q000032:analysis / Q000378:metabolism; D010759:Phosphorus Isotopes; D012016:Reference Values; D012680:Sensitivity and Specificity; D013997:Time Factors
D010759:Phosphorus Isotopes; D010725:Phosphocreatine; D000255:Adenosine Triphosphate