[Cardiac energy metabolism in heart valve diseases with 31P MR spectroscopy].
OBJECTIVE
Heart valve disease combined with left ventricular hypertrophy leads to derangements in cardiac energy metabolism, which can be detected non-invasively by 31P-MR-spectroscopy. The purpose of the present study was to examine whether the derangements in cardiac metabolism are reversible after surgical valve replacement.


METHODS
10 healthy volunteers and 10 patients with aortic stenosis (pressure gradients > 60 mmHg) were included. For assessment of energy metabolism, 31P-MR spectra were obtained with a double oblique 3D-CSI technique (voxel size 25 cm3). In 5 of 10 patients, follow-up examination was performed 3 months after surgical valve replacement (SVR). Left ventricular (LV) function was analyzed by cine MRI.


RESULTS
Before SVR the myocardial phosphocreatine to adenosinetriphosphate (PCr-ATP) ratio was significantly (p = 0.0002) reduced to 0.80 +/- 0.25 in patients compared to 1.65 +/- 0.21 in volunteers. 3 months after SVR, LV mass had significantly (p = 0.04) decreased from 238 +/- 33 g to 206 +/- 47 g. At the same time a significant (p = 0.04) increase of the PCr-ATP ratio from 0.80 +/- 0.25 to 1.28 +/- 0.22 was observed. A slight, but not significant, reduction of the phosphodiester ATP ratio was observed before SVR, with a trend towards normalization after SVR.


CONCLUSIONS
After SVR, the deranged energy metabolism shows a trend towards normalization. Further follow-up is necessary to determine whether complete normalization of the energetic derangement can be observed over longer periods of time following SVR.
Beer
M
M
Institut für Röntgendiagnostik, Universität Würzburg. meinrad.beer@mail.uni-wuerzburg.de
Viehrig
M
M
Seyfarth
T
T
Sandstede
J
J
Lipke
C
C
Pabst
T
T
Kenn
W
W
Harre
K
K
Horn
M
M
Landschütz
W
W
von Kienlin
M
M
Neubauer
S
S
Hahn
D
D
D000328:Adult; D000368:Aged; D001024:Aortic Valve Stenosis / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D011183:Postoperative Complications / Q000175:diagnosis / Q000503:physiopathology; D012016:Reference Values; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000502:physiology
D010710:Phosphates