Evaluation of Myocardial Triglyceride Accumulation Assessed on ¹H-Magnetic Resonance Spectroscopy in Apparently Healthy Japanese Subjects

Abstract

Objective Proton magnetic resonance spectroscopy ( 1 H-MRS) enables the clinician to noninvasively assess the amount of ectopic fat in the liver, skeletal muscle and myocardium. Recent studies have reported that the myocardial triglyceride (TG) content is associated with aging, metabolic disorders and cardiac dysfunction. However, the clinical usefulness of myocardial TG measurements in Japanese subjects has not been fully investigated. Methods The myocardial TG content was evaluated using 1 H-MRS in 37 apparently healthy Japanese subjects, and the left ventricular function was measured on cardiac magnetic resonance imaging (MRI). Blood pressure, body composition and biochemical markers were measured in a fasting state, and cardiopulmonary exercise testing (CPX) was performed to evaluate exercise capacity. Results The mean myocardial TG content was 0.85±0.40%. The myocardial TG content was significantly associated with the percent body fat (r=0.39), serum triglyceride level (r=0.40), estimated glomerular filtration rate (r=-0.37), anaerobic threshold (r=-0.36), maximal load of CPX (r=0.39), left ventricular enddiastolic volume (r=-0.41) and left ventricular end-systolic volume (LVESV) (r=-0.51) (all: p<0.05). In a multivariate analysis, the LVESV was found to be an independent factor of the myocardial TG content. Conclusion1 H-MRS may be useful for assessing the associations between the myocardial TG content and various clinical parameters, including those reflecting obesity, metabolic disorders, cardiac morphology and exercise capacity, noninvasively, even in Japanese subjects.

A prospective randomized study comparing effects of empagliflozin to sitagliptin on cardiac fat accumulation, cardiac function, and cardiac metabolism in patients with early-stage type 2 diabetes: the ASSET study

“…Such differences in evaluation methods may also account for the different results in cardiac fat accumulation between the present and previous studies. Moreover, myocardial triglyceride content was unaffected despite its baseline value being higher in our subjects than in healthy Japanese subjects [37] or patients with left ventricular hypertrophy [38]. This result is consistent with that of a previous one-arm study showing that 6 months of empagliflozin treatment did not impact myocardial triglyceride content [45].…”

“…The myocardial triglyceride content was measured by 1 H-MRS analysis using a 1.5 T whole-body MR scanner (MAGNETOM AvantoSQ 1.5 T B-19) performed by specialists with dedicated software (Argus; Siemens), as described previously [36][37][38]. The volume of interest (VOI = 10 × 10 × 20 mm 3 ) was manually placed on the ventricular septum of the cine images of the heart and adjusted to fit the ventricular septum of the LV.…”

Triglyceride Deposit Cardiomyovasculopathy with Massive Myocardial Triglyceride which Was Proven Using Proton-magnetic Resonance Spectroscopy

“…In addition, we previously reported the levels of myocardial TG content in apparently healthy subjects without coronary heart disease, endurance athletes, and healthy subjects with fitness habits as 0.85%±0.40%, 0.60%±0.20%, and 0.89%±0.41%, respectively ( 11 , 12 ). On the other hand, the levels of myocardial TG content in patients with hypertrophic cardiomyopathy (HCM) and hypertensive heart disease were 1.09%±0.72% and 2.14%±1.29%, respectively ( 13 ).…”

Myocardial Triglyceride Content and Late Gadolinium Enhancement in Hypertrophic Cardiomyopathy with Asymmetric Septal Hypertrophy

“…The MTG level was expressed as the ratio of lipid to water (%). 1 H-MRS evaluation of MTG content was performed essentially as previously described [13,20,21].…”