19 research outputs found
Wide limits of agreement between left ventricular stroke volume, right ventricular stroke volume and aortic and pulmonary forward flow
Physical Self-Concept and Physical Activity in Children with Congenital Heart Defects—Can We Point Out Differences to Healthy Children to Promote Physical Activity?
Objective: Children with congenital heart defects (CHD) are at high risk for cardiovascular disease in addition to their congenital disease, so it is important to motivate this group of patients to live a physically active lifestyle. A potential influencing determinant of younger children’s physical performance is the physical self-concept. The objective of the present study was first to evaluate the correlation between the physical self-concept (PSC) and the participation in physical activities (PA) of a representative group of children with congenital heart disease (CHD), and second to point out differences in comparison to their healthy peer group. Methods: Using the database of PA of the S-BAHn-Study we focused on physical self-concept assessed by the German version of the Physical Self-Description Questionnaire. We compare the obtained data of children with CHD to a representative age-matched sample of 3.385 participants of the Motorik Modul Study. Results: N = 1.198 complete datasets could be included in the analyses. The mean age of patients was 11.6 ± 3.1 years. For the total cohort of patients with CHD and the reference group, PA correlated significantly with a positive PSC (p 0.24). Conclusions: According to this representative survey, there is a clear relation between PA and PSC in the cohort of healthy children and the group of children with CHD throughout the severity of their heart defects. Although PSC did not differ in patients with simple CHD and their healthy peer group, PA was significantly reduced. This gap invites us to reflect on how we could break new ground to promote a physically active lifestyle in children with CHD regardless of the severity of their cardiac defects
Liraglutide restores impaired associative learning in individuals with obesity
Survival under selective pressure is driven by the ability of our brain to use sensory information to our advantage to control physiological needs. To that end, neural circuits receive and integrate external environmental cues and internal metabolic signals to form learned sensory associations, consequently motivating and adapting our behaviour. The dopaminergic midbrain plays a crucial role in learning adaptive behaviour and is particularly sensitive to peripheral metabolic signals, including intestinal peptides, such as glucagon-like peptide 1 (GLP-1). In a single-blinded, randomized, controlled, crossover basic human functional magnetic resonance imaging study relying on a computational model of the adaptive learning process underlying behavioural responses, we show that adaptive learning is reduced when metabolic sensing is impaired in obesity, as indexed by reduced insulin sensitivity (participants: N = 30 with normal insulin sensitivity; N = 24 with impaired insulin sensitivity). Treatment with the GLP-1 receptor agonist liraglutide normalizes impaired learning of sensory associations in men and women with obesity. Collectively, our findings reveal that GLP-1 receptor activation modulates associative learning in people with obesity via its central effects within the mesoaccumbens pathway. These findings provide evidence for how metabolic signals can act as neuromodulators to adapt our behaviour to our body’s internal state and how GLP-1 receptor agonists work in clinics
Adjustment of the velocity encoding parameter to the blood flow velocity is not necessary for accurate and precise quantification of aortic regurgitation severity with phase contrast magnetic resonance imaging
Indirect quantification of mitral regurgitation using cardiovascular magnetic resonance: A comparison of techniques
Reliable phase-contrast flow volume magnetic resonance measurements are feasible without adjustment of the velocity encoding parameter
Purpose: To show that adjustment of velocity encoding (VENC) for phase-contrast (PC) flow volume measurements is not necessary in modern MR scanners with effective background velocity offset corrections. Approach: The independence on VENC was demonstrated theoretically, but also experimentally on dedicated phantoms and on patients with chronic aortic regurgitation (n = 17) and one healthy volunteer. All PC measurements were performed using a modern MR scanner, where the pre-emphasis circuit but also a subsequent post-processing filter were used for effective correction of background velocity offset errors. Results: The VENC level strongly affected the velocity noise level in the PC images and, hence, the estimated peak flow velocity. However, neither the regurgitant blood flow volume nor the mean flow velocity displayed any clinically relevant dependency on the VENC level. Also, the background velocity offset was shown to be close to zero
Reply to “Comment on aortic size predicts aortic dissection in Turner syndrome - A 25-year prospective cohort study” by Salman Khazaei
Aortic size predicts aortic dissection in Turner syndrome - A 25-year prospective cohort study
Background: Women with Turner syndrome (TS) have an increased risk of aortic dissection. The current recommended cutoff to prevent aortic dissection in TS is an aortic size index (ASI) of ≥2.5 cm/m2. This study estimated which aortic size had the best predictive value for the risk of aortic dissection, and whether adjusting for body size improved risk prediction. Methods: A prospective, observational study in Sweden, of women with TS, n = 400, all evaluated with echocardiography of the aorta and data on medical history for up to 25 years. Receiver operating characteristic (ROC) curves, sensitivity and specificity were calculated for the absolute ascending aortic diameter (AAD), ascending ASI and TS specific z-score. Results: There were 12 patients (3%) with aortic dissection. ROC curves demonstrated that absolute AAD and TS specific z-score were superior to ascending ASI in predicting aortic dissection. The best cutoff for absolute AAD was 3.3 cm and 2.12 for the TS specific z-score, respectively, with a sensitivity of 92% for both. The ascending ASI cutoff of 2.5 cm/m2 had a sensitivity of 17% only. Subgroup analyses in women with an aortic diameter ≥ 3.3 cm could not demonstrate any association between karyotype, aortic coarctation, bicuspid aortic valve, BMI, antihypertensive medication, previous growth hormone therapy or ongoing estrogen replacement treatment and aortic dissection. All models failed to predict a dissection in a pregnant woman. Conclusions: In Turner syndrome, absolute AAD and TS-specific z-score were more reliable predictors for aortic dissection than ASI. Care should be taken before and during pregnancy
GLP-1 and hunger modulate incentive motivation depending on insulin sensitivity in humans
Objective: To regulate food intake, our brain constantly integrates external cues, such as the incentive value of a potential food reward, with internal state signals, such as hunger feelings. Incentive motivation refers to the processes that translate an expected reward into the effort spent to obtain the reward; the magnitude and probability of a reward involved in prompting motivated behaviour are encoded by the dopaminergic (DA) midbrain and its mesoaccumbens DA projections. This type of reward circuity is particularly sensitive to the metabolic state signalled by peripheral mediators, such as insulin or glucagon-like peptide 1 (GLP-1). While in rodents the modulatory effect of metabolic state signals on motivated behaviour is well documented, evidence of state-dependent modulation and the role of incentive motivation underlying overeating in humans is lacking. Methods: In a randomised, placebo-controlled, crossover design, 21 lean (body mass index [BMI] < 25 kg/m(2)) and 16 obese (BMI3 30 kg/m(2)) volunteer participants received either liraglutide as a GLP-1 analogue or placebo on two separate testing days. Incentive motivation was measured using a behavioural task in which participants were required to exert physical effort using a handgrip to win different amounts of food and monetary rewards. Hunger levels were measured using visual analogue scales; insulin, glucose, and systemic insulin resistance as assessed by the homeostasis model assessment of insulin resistance (HOMA-IR) were quantified at baseline. Results: In this report, we demonstrate that incentive motivation increases with hunger in lean humans (F-(1,F-42) = 5.31, p = 0.026, beta = 0.19) independently of incentive type (food and non-food reward). This effect of hunger is not evident in obese humans (F-(1,F-62) = 1.93, p = 0.17, beta = -0.12). Motivational drive related to hunger is affected by peripheral insulin sensitivity (two-way interaction, F-(1,F- (35)) = 6.23, p = 0.017, beta = -0.281). In humans with higher insulin sensitivity, hunger increases motivation, while poorer insulin sensitivity dampens the motivational effect of hunger. The GLP-1 analogue application blunts the interaction effect of hunger on motivation depending on insulin sensitivity (three-way interaction, F-(1,F- 127) = 5.11, p = 0.026); no difference in motivated behaviour could be found between humans with normal or impaired insulin sensitivity under GLP-1 administration. Conclusion: We report a differential effect of hunger on motivation depending on insulin sensitivity. We further revealed the modulatory role of GLP-1 in adaptive, motivated behaviour in humans and its interaction with peripheral insulin sensitivity and hunger. Our results suggest that GLP-1 might restore dysregulated processes of midbrain DA function and hence motivational behaviour in insulin-resistant humans. (C) 2021 The Author(s). Published by Elsevier GmbH