Detection of myocardial infarctions by acquisition-weighted 31P-MR spectroscopy in humans.
OBJECTIVE
To determine whether the recently applied technique of acquisition-weighted 31P-MR spectroscopy (AW-MRS) allows for the detection of depressed energy metabolism in patients with inferior wall myocardial infarctions.


METHODS
Eight patients with subacute myocardial infarction and wall motion abnormalities restricted to the inferior wall were examined with a 1.5-T MR scanner. Global and regional left ventricular (LV) function was assessed by cine MRI, and the size and extent of myocardial infarction was assessed by late enhancement (LE). MRS was performed with an AW three-dimensional chemical shift imaging sequence. Phosphocreatine/ATP ratios were determined with the postprocessing model AMARES for four voxels positioned in the anterior, lateral, inferior, and septal parts of the LV.


RESULTS
The LV ejection fraction (EF) was reduced to 37.5%+/-9.0%. Seven of eight patients had transmural LE in the inferior wall, and one patient showed subendocardial enhancement in the inferior-lateral parts. Phosphocreatine/ATP ratios of the inferior wall were significantly reduced (P <0.05) compared to all other parts of the LV (1.03 +/- 0.39 (inferior), 1.67 +/- 0.81 (lateral), 1.73 +/- 0.29 (anterior), and 1.49 +/- 0.31 (septal)). The ratios in five of seven patients with transmural enhancement were <1.00 in the inferior wall.


CONCLUSIONS
Acquisition weighting allows for the detection of inferior wall infarctions in patients. Transmural signal enhancement is associated with significant depression of phosphocreatine/ATP ratios.
Beer
Meinrad
M
Institut für Röntgendiagnostik, Universität Würzburg, Würzburg, Germany. beer@roentgen.uni-wuerzburg.de
Spindler
Matthias
M
Sandstede
Joern J W
JJ
Remmert
Haiko
H
Beer
Stephanie
S
Köstler
Herbert
H
Hahn
Dietbert
D
D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D000368:Aged; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D010725:Phosphocreatine / Q000378:metabolism; D010759:Phosphorus Isotopes; D012016:Reference Values; D018709:Statistics, Nonparametric
D010759:Phosphorus Isotopes; D010725:Phosphocreatine; D000255:Adenosine Triphosphate