Determination of triglyceride in the human myocardium by magnetic resonance spectroscopy: reproducibility and sensitivity of the method.
The primary aim of this investigation was to determine the reliability and sensitivity of 1H magnetic resonance spectroscopy (1H-MRS) as a method for quantifying myocardial triglyceride (TG) content in humans over time and in response to metabolic perturbations. Three separate experiments were designed to quantify myocardial TG content 1) over a 90-day period, 2) after a high-fat meal, and 3) after a 48-h fast. Proton spectra were collected from a 10 x 20 x 30-mm3 voxel placed within the intraventricular septum, with measurements acquired at end-systole and end-expiration, using cardiac triggering and respiratory gating. Minimal variation was observed between myocardial TG content determined 90 days apart (r = 0.98, CV = 5%), whereas TG values were unaffected by a high-fat meal despite a significant twofold increase (P < 0.05) in serum TG. In contrast, myocardial TG content increased threefold (P < 0.05) after a 48-h fast despite a 25% reduction in serum TG. Body mass index was significantly related to myocardial TG (r = 0.58, P < 0.05) and the change in myocardial TG after a 48-h fast (r2 = 0.60). 1H-MRS is a reliable method for the determination of myocardial TG in humans and is relatively unaffected by the consumption of one high-fat meal but sensitive to changes following a prolonged fast.
Department of Internal Medicine, Univ. of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd., Dallas, TX 75390-8899, USA.
Jason S
JS
Reingold
Jonathan M
JM
McGavock
Shaheen
S
Kaka
Tommy
T
Tillery
Ronald G
RG
Victor
Lidia S
LS
Szczepaniak
D004041:Dietary Fats / Q000008:administration & dosage; D005260:Female; D005508:Food Deprivation / Q000502:physiology; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods* / Q000592:standards; D008297:Male; D009206:Myocardium / Q000737:chemistry* / Q000378:metabolism; D015203:Reproducibility of Results; D014280:Triglycerides / Q000032:analysis* / Q000378:metabolism
D004041:Dietary Fats; D014280:Triglycerides