Decreased high-energy phosphate ratios in the myocardium of men with diabetes mellitus type I.
OBJECTIVE
To investigate whether alterations in high-energy phosphates occur in the myocardium of persons with diabetes mellitus type I. Microvascular abnormalities and dysfunction via thickening of the basement membrane are known to occur in diabetic patients. Myocardial high-energy phosphates have been shown to be reduced by ischemia, and alterations of the cardiac metabolism are the primary consequence of myocardial ischemia.


METHODS
The present study involved 34 male patients (mean age 35.5 +/- 10.1) with diabetes mellitus type I and 35 healthy male volunteers (mean age 36 +/- 8.6) as age-matched controls. Phosphorus-31 magnetic resonance spectroscopic imaging of the heart was performed in all subjects using a 1.5-T whole-body magnetic resonance scanner. The ratios of phosphocreatine (PCr) to beta-adenosinetriphosphate (beta-ATP) were calculated. Moreover, echocardiographic evaluation and stress tests were performed in all individuals.


RESULTS
The myocardium of patients with diabetes mellitus type I showed significantly decreased ratios of PCr to beta-ATP compared with healthy controls in the left ventricle (1.90 +/- 0.4 vs. 2.15 +/- 0.3, p < 0.05). We found a moderate negative correlation between the ratio of PCr to beta-ATP in the left ventricle and both, the diastolic left ventricular function (E/A; r = -0.41) and the glycohemoglobin A1c (GHbA1c; r = -0.42).


CONCLUSIONS
This study demonstrates for the first time a decreased ratio of PCr to beta-ATP in the myocardium of persons with diabetes mellitus type I without a known history of coronary heart disease.
Metzler
Bernhard
B
Division of Cardiology, University Hospital Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria. bernhard.metzler@uibk.ac.at
Schocke
Michael F H
MF
Steinboeck
Peter
P
Wolf
Christian
C
Judmaier
Werner
W
Lechleitner
Monika
M
Lukas
Peter
P
Pachinger
Otmar
O
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000328:Adult; D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D003627:Data Interpretation, Statistical; D003922:Diabetes Mellitus, Type 1 / Q000378:metabolism* / Q000503:physiopathology; D004452:Echocardiography; D005080:Exercise Test; D006442:Glycated Hemoglobin / Q000378:metabolism; D006352:Heart Ventricles / Q000378:metabolism; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D010725:Phosphocreatine / Q000378:metabolism*; D010759:Phosphorus Isotopes; D018487:Ventricular Dysfunction, Left / Q000503:physiopathology
D000255:Adenosine Triphosphate; D015415:Biomarkers; D006442:Glycated Hemoglobin; D010725:Phosphocreatine; D010759:Phosphorus Isotopes