Aims: To quantify metabolic impairment via a one-factor approach with confirmatory factor analysis (CFA) including MRI-derived visceral and subcutaneous adipose tissues and to associate it with... Show moreAims: To quantify metabolic impairment via a one-factor approach with confirmatory factor analysis (CFA) including MRI-derived visceral and subcutaneous adipose tissues and to associate it with diastolic dysfunction. Methods: In this cross-sectional analysis, 916 participants (53% female, mean age (SD): 56 (6)) underwent abdominal and cardiovascular MRI. With CFA a metabolic-load factor of metabolic-syndrome variables and visceral and subcutaneous adipose tissues was constructed. A piecewise structural equation model approach with adjustment for confounding factors was used to determine associations with left-ventricular diastolic function, cardiac morphology and hemodynamics. Results: Model fitting excluding blood pressure and waist circumference but including visceral and subcutaneous adipose tissues, fasting glucose, HDL-c and triglycerides was used to construct the metabolic-load factor. Evaluating measurement invariance demonstrated sex-specificity. Change in mitral early/late peak filling rate ratio was -0.12 for both males [-0.20; -0.05, p > 0.05] and females [-0.17; -0.07, p > 0.001] per SD of metabolicload factor. Change in deceleration time of mitral early filling was -11.83 ms in females [-17.38; -6.27] per SD of metabolic-load factor. Conclusion: A single latent metabolic-load factor via CFA including MRI-derived adipose tissues increased sensitivity for metabolic impairment obsoleting waist circumference and is associated with a decreased leftventricular diastolic function, more apparent in females than in males. Show less
The aim of this thesis was to evaluate quantitative MRI techniques in reno-cardiovascular health, and to study the links between obesity and reno-cardiovascular health using quantitative MRI... Show moreThe aim of this thesis was to evaluate quantitative MRI techniques in reno-cardiovascular health, and to study the links between obesity and reno-cardiovascular health using quantitative MRI metrics. Furthermore, we aimed to address novel insights on the safety of contrast media with regard to the use of gadolinium. The general introduction (Chapter 1) of this thesis introduces the concept of quantitative MRI, its application in epidemiological research, reno-cardiovascular health, and in obesity. In addition, the general introduction addresses the safety of gadolinium as an MRI contrast agent. Following the general introduction a review of the clinical application and technical considerations of quantitative MRI using T1 and T2(*) mapping in cardiac and renal imaging was provided in Chapter 2. Part 1 of this thesis focused on the reproducibility and clinical validity of T1 mapping and proton magnetic resonance spectroscopy (1H-MRS) in renal imaging. Part 2, described different studies evaluating the association between obesity and reno-cardiovascular function which was analyzed in population-based imaging studies using different quantitative MRI metrics. Part 3, provides an overview of the safety profile of gadolinium containing contrast agents, and reflection on the recent EMA recommendations. Show less
Aims We aimed to evaluate the associations of body fat distribution with cardiovascular function and geometry in the middle-aged general population.Methods and results Four thousand five hundred... Show moreAims We aimed to evaluate the associations of body fat distribution with cardiovascular function and geometry in the middle-aged general population.Methods and results Four thousand five hundred and ninety participants of the UK Biobank (54% female, mean age 61.1 +/- 7.2 years) underwent cardiac magnetic resonance for assessment of left ventricular (LV) parameters [end-diastolic volume (EDV), ejection fraction (EF), cardiac output (CO), and index (CI)] and magnetic resonance imaging for body composition analysis [subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT)]. Body fat percentage (BF%) was assessed by bioetectrical impedance. Linear regressions were performed to assess the impact of visceral (VAT) and general (SAT and BF%) obesity on cardiac function and geometry. Visceral obesity was associated with a smaller EDV [VAT: beta -1.74 (-1.15 to -2.33)1, lower EF NAT: beta -0.24 (-0.12 to -0.35), SAT: beta 0.02 (-0.04 to 0.08), and BF%: beta 0.02 (-0.02 to 0.06)] and the strongest negative association with CI [VAT: beta -0.05 (-0.06 to -0.04), SAT: beta -0.02 (-0.03 to -0.01), and BF% beta -0.01 (-0.013 to -0.007)]. In contrast, general obesity was associated with a larger EDV [SAT: beta 1.01 (0.72-1.30), BF%: beta 0.37 (0.23-0.51)] and a higher CO [SAT: beta 0.06 (0.05-0.07), BF%: beta 0.02 (0.01-0.03)]. In the gender-specific analysis, only men had a significant association between VAT and EF [beta -0.35 (-0.19 to -0.51)].Conclusions Visceral obesity was associated with a smaller LV EDV and subclinical lower LV systolic function in men, suggesting that visceral obesity might play a more important role compared to general obesity in LV remodelling. Show less
