Visceral abdominal fat has been associated to cardiovascular risk factors and coronary artery disease (CAD). Computed tomography (CT) coronary angiography is an emerging technology allowing detection of both obstructive and nonobstructive CAD adding information to clinical risk stratification. The aim of this study was to evaluate the association between CAD and adiposity measurements assessed clinically and by CT. We prospectively evaluated 125 consecutive subjects (57% men, age 56.0+/-12 years) referred to perform CT angiography. Clinical and laboratory variables were determined and CT angiography and abdominal CT were performed in a 64-slice scanner. CAD was defined as any plaque calcified or not detected by CT angiography. Visceral and subcutaneous adiposity areas were determined at different intervertebral levels. CT angiography detected CAD in 70 (56%) subjects, and no association was found with usual anthropometric adiposity measurements (waist and hip circumferences and body mass index). Otherwise, CT visceral fat areas (VFA) were significantly related to CAD. VFA T12-L1 values > or =145cm(2) had an odds ratio of 2.85 (95% CI 1.30-6.26) and VFA L4-L5 > or =150cm(2) had a 2.87-fold (95% CI 1.31-6.30) CAD risk. The multivariate analysis determined age and VFA T12-L1 as the only independent variables associated to CAD. Visceral fat assessed by CT is an independent marker of CAD determined by CT angiography.
Inflammation promotes adverse ventricular remodeling. T1 mapping has been used to non-invasively assess interstitial myocardial fibrosis. We examined the association of baseline markers of systemic inflammation with interstitial myocardial fibrosis measured by extracellular volume fraction and native T1 mapping at 10 years’ follow-up in the Multi-Ethnic Study of Atherosclerosis. 772 participants had complete baseline data and underwent cardiac magnetic resonance imaging. All analyses were stratified by sex. Multivariable linear regression models were constructed to assess the associations of baseline C-Reactive Protein, interleukin 6 and fibrinogen with native T1 time and extracellular volume fraction. Longer native T1 times and higher percentages of extracellular volume fraction represent increasing myocardial fibrosis. A one standard deviation increment of log-transformed interleukin 6 levels was associated with 0.4% higher extracellular volume fraction in males (β= 0.4; p= 0.05). C-Reactive Protein and fibrinogen were not associated to extracellular volume fraction. A one standard deviation increment in the log-transformed CRP levels was associated with 4.9 ms higher native T1 (β = 4.9; p= 0.03). In females, the inflammatory markers did not demonstrate association with native T1 nor extracellular volume fraction. Higher interleukin 6 and C-Reactive Protein levels are associated with increased interstitial myocardial fibrosis assessed by cardiac magnetic resonance in males. However, no inflammatory markers were associated to myocardial fibrosis in females.
Background: Previous studies showed that the quantity of the left atrial (LA) periatrial fat tissue predicts recurrence after catheter ablation of atrial fibrillation (AF). We hypothesized that the quality of the LA periatrial fat tissue, measured by the mean computed tomography attenuation, predicts recurrence after AF ablation independent of the quantity of the LA periatrial fat tissue. Methods: We included 143 consecutive patients with drug-refractory AF referred for the first catheter ablation of AF (62.2±10 years, 40% nonparoxysmal AF). All participants had a preablation cardiac computed tomography. We measured the quantity of the LA periatrial fat tissue by the area (millimeter square) and the quality by the mean computed tomography attenuation (Hounsfield units) in a standard 4-chamber view. Results: Patients with AF recurrence after ablation (n=57) had a significantly larger fat area (167.6 [interquartile range, 124.1–255] versus 145.4 [95.6–229.3] mm 2 ; P =0.018) and a higher fat attenuation (−92.0±9.8 versus −96.5±9.4 Hounsfield units; P =0.006) than those without recurrence (controls). LA fat attenuation was correlated with LA fat volume and LA bipolar voltage by invasive mapping and was associated with AF recurrence after adjusting for clinical risk factors, including body mass index, AF type, LA dimension, and fat area (hazard ratio, 2.65; P =0.001). Conclusions: The quality of the LA periatrial fat tissue is an independent predictor of recurrence after the first AF ablation. Assessment of LA periatrial fat attenuation can improve AF ablation outcomes by refining patient selection.
Aims To evaluate whether myocardial fibrosis predicts cardiovascular events (CVEs) and mortality in the Multi-Ethnic Study of Atherosclerosis. Methods and results Cardiac magnetic resonance (CMR) T1 mapping with gadolinium administration for assessment of extracellular volume fraction (ECV) was performed in 1326 participants, in whom myocardial scar was assessed by late gadolinium enhancement (LGE). The clinical outcomes were defined as all-cause mortality, atherosclerotic CVEs, and incident heart failure (HF) during an average of 8 years of follow-up after the scan. Participants’ mean native T1 time was 971 ms [standard deviation (SD) 45.5], ECV was 27 (SD 2.9), and 117 (8.8%) of them had LGE. At the time of the CMR exam, participant age was 68 years (SD 9) and 48% of them were women. Ideal cut-offs were identified using classification and regression trees accounting for time-to-event outcomes for ECV (30%) and native T1 time (954 ms). Over the follow-up period, 106 participants died, 78 developed CVE, and 23 developed HF. After adjustment for risk factors, ECV >30% was associated with death [hazard ratio (HR): 1.67, P < 0.05], incident CVE (HR: 2.02, P < 0.05), and incident HF (HR: 2.85, P < 0.05). After adjustments, native T1 >954 ms was associated with incident CVE (HR: 2.09, P < 0.05). Myocardial scar by LGE was not predictive of clinical outcomes after adjustments. Conclusion ECV is an independent prognostic marker of incident HF, atherosclerotic CVEs, and all-cause mortality. ECV, with its ability to characterize both diffuse and focal fibrosis processes, better predicted incident events than regional myocardial abnormalities as visualized by LGE imaging in a large multi-ethnic population.
Objective: Discrimination and bullying are common conditions among LGBT people. During schooling, these practices compromising education. The aim of this study is to evaluate educational attainment among Brazilian transgender women (TW) and how their education level affects the risk of HIV infection. Study design: a cross-sectional population-based study. Subjects and methods: 95 adult TW were selected. Information concerning verbal and physical aggression, school dropout, school years (SY), and educational level were assessed. HIV status was screened using a fourthgeneration immunoassay followed by western blot testing. Results: The mean of SY was 9.1 ± 3.8 ys. The mean age at school dropout was 16.3 ± 3.4 ys old. Verbal aggression was reported by 83%, physical by 48%, and 18% of the TW dropped out school immediately after being physically assaulted. Participants who suffered physical aggression attended school for almost 4 years less than those participants who did not suffer this abuse (OR =-3.96, p < 0.0001). A similar result was found for verbal aggression (OR =-4.35; p < 0.0001). HIV/AIDS prevalence was 18% (n = 17). The mean of SY among HIV/AIDS positive and negative individuals were 6.8 ± 43 versus 9.7 ± 3, respectively (p = 0.004). Lower education was associated with higher frequency of HIV/AIDS among TW and this relationship was sustained after adjustment for injectable drug use and sex work (OR = 0.79, p = 0.04). Conclusion: Among Brazilian TW, lower education level was a risk factor associated with HIV. The reasons for low schooling among TW are multifactorial, but verbal and physical harassment strongly contribute for it.
The selection of production strategy under uncertainties is a complicated task due to the high number of variables and uncertainties. While new information aims to reduce the uncertainty of one or more variables, consequently reducing the risk, flexibility may be used to change field operation in the future. The objective of this work is to estimate the value of flexibility through a risk-return analysis in which a company profile is taken into account represented by the iso-utility curve. The methodology is an extension from Value of Information (VoI) assessment under uncertainties. It comprises a complete uncertainty analysis, use of representative models, generation of risk curves, optimization steps to define the strategy without flexibility which is then simulated in several scenarios verifying the bottlenecks of the strategy that may be assessed through flexibility. Finally, the benefit of each selected flexibility is estimated through risk-return analysis. The work includes a Latin Hypercube technique to combine uncertain scenarios and the use of an assisted optimization procedure to select the production strategy. It is then applied to a 28° API, low viscosity offshore oil field including production history. Results indicate that this methodology is able to identify flexibility, in this case, the expansion of production capacity, which is then added to the production strategy with two objectives: to mitigate risk and to increase value. The tested flexibility changes the project risk and return in both objectives and allows the company to produce more efficiently in different scenarios, by producing with a higher use of installed capacity. The main conclusions are that the flexibility of production capacity expansion can be used not only to mitigate risk, but also for value creation, allowing the company to adapt its production strategy as new information is revealed. The main contribution of this work is a new perspective in risk assessment from a probabilistic point of view, combining production strategy selection and optimization, numeric reservoir simulation and risk-return analysis. The flexibility is an alternative to information for risk mitigation, with the advantage of not holding the project back to collect new data. Furthermore, flexibilities can also be used to exploit the upside of the uncertainty if, during the production phase, such scenarios occur.
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