Dynamics of right ventricle contractility after cardiac surgery of tricuspid valve

Funding Acknowledgements

Type of funding sources: None.

Background

The function of right ventricle (RV) is an independent prognostic factor for patients with valvular heart disease. However, changes in RV function parameters in patients with and without tricuspid valve operations after cardiac surgery are lack known. The aim of the study was to define changes in RV parameters after cardiac surgery in patients with left-sided valve diseases.

Methods

Fifty-five consecutive patients (33 men, 61 ± 10 years old), who were referred for the repair and/or replacement of left-sided valves, were included in the study. A transthoracic echocardiography assessment before and an average of 109 days (91-114) following the operation was performed. Tricuspid annular plane systolic excursion (TAPSE), fractional area change RV (FAC), strain of the RV free wall (SRV), and right atrial volume were assessed in groups of patients with and without tricuspid valve repair.

Results

Valve repair for secondary tricuspid regurgitation was performed in nineteen patients undergoing left-sided valve surgery. Thirty-six patients had repair and/or replacement of left-sided valves without a tricuspid valve operation. There was a strong correlation between TAPSE, FAC, and RV strain before the operation (R = 0.62-0.77, p < 0.000002). However, there was no correlation between TAPSE and FAC; TAPSE and RV strain after the operation. TAPSE and RV strain significantly decreased after the operations and were below the normal range in both the groups of patients with and without tricuspid valve repair. TAPSE was 21 ± 5mm before the operation vs. 14 ± 4 mm after operation, p < 0.0000001 for all patients (20 ± 5mm vs. 13 ± 3 mm, p < 0.0003 for the group which underwent tricuspid valve repair; 22 ± 4mm vs. 14 ± 4 mm, p < 0.000001 for tricuspid valves which were not operated on). RV strain was -19 ± 6 mm before operating vs. -16 ± 5mm after operating, p < 0.0004 for all patients (-20 ± 6mm vs. -15 ± 5mm, p < 0.006 for tricuspid valve repair; -19 ± 6mm vs. -16 ± 4 mm, p < 0.02 for the tricuspid valves which were not operated on).  There was no difference in TAPSE and SRV among patients with and without tricuspid valve repair. Decreased longitudinal function parameters (TAPSE and SRV) didn’t correlate with patients’ clinical status or with normalized right chambers volumes. FAC was 39 ± 11% before operating vs. 41 ± 9% after the operation, p = 0.45 for all patients (37 ± 13% vs. 40 ± 8%, p = 0.69 for the group which underwent tricuspid valve repair; 40 ± 10% vs. 41 ± 9%, p = 0.52 for the group with tricuspid valves which were not operated on). An increase in FAC correlated with a decrease in right chamber sizes after operations (R=-0.37, p < 0.03).

Conclusion

Longitudinal right ventricle parameters (TAPSE, SRV) significantly decrease after valve operations in groups with and without tricuspid valve repair. However, there is no correlation with the clinical status of patients. Global function parameters (FAC) correlates with the normalization of right chamber size after cardiac operation.

Design modifications to Rotating Modulation Collimators for extended field-of-view

Rotating Modulation Collimators (RMC) are devices that can be used to determine the location of a radiation source. In this work, a design with extended field-of-view (FOV) is proposed to allow faster measurements by providing a wider scanned area. Monte Carlo simulations were used to calculate the response of the RMC system, system matrix and modulation profiles. The Maximum Likelihood Expectation Maximization algorithm was used for image reconstruction. The proposed design provides a FOV up to 60° with a maximum error of 5° or up to 70° with a maximum error of 15°.

Blue emission at atomically sharp 1D heterojunctions between graphene and h-BN

Atomically sharp heterojunctions in lateral two-dimensional heterostructures can provide the narrowest one-dimensional functionalities driven by unusual interfacial electronic states. For instance, the highly controlled growth of patchworks of graphene and hexagonal boron nitride (h-BN) would be a potential platform to explore unknown electronic, thermal, spin or optoelectronic property. However, to date, the possible emergence of physical properties and functionalities monitored by the interfaces between metallic graphene and insulating h-BN remains largely unexplored. Here, we demonstrate a blue emitting atomic-resolved heterojunction between graphene and h-BN. Such emission is tentatively attributed to localized energy states formed at the disordered boundaries of h-BN and graphene. The weak blue emission at the heterojunctions in simple in-plane heterostructures of h-BN and graphene can be enhanced by increasing the density of the interface in graphene quantum dots array embedded in the h-BN monolayer. This work suggests that the narrowest, atomically resolved heterojunctions of in-plane two-dimensional heterostructures provides a future playground for optoelectronics.

Here, the authors explore the blue photoluminescence signal arising from the interface between graphene and h-BN arranged in in-plane heterostructures, and fabricate a blue light emitting device utilizing the heterojunction as the emitting layer.

SAT0286 BIOLOGICAL CORRELATES OF RADIOGRAPHIC FEATURES OF INTERSTITIAL LUNG DISEASE IN SYSTEMIC SCLEROSIS: AN IN DEPTH ANALYSIS OF BRONCHOALVEOLAR PROTEINS OF SCLERODERMA LUNG STUDY I PARTICIPANTS

Background:

Systemic sclerosis-related interstitial lung disease (SSc-ILD) involves a combination of inflammation, fibrosis and vascular pathology that is typically assessed on CT imaging as a mixture of ground-glass opacification (GGO) and fibrotic changes. We hypothesized that proteins recovered from bronchoalveolar lavage (BAL) could be used to probe the underlying pathobiology associated with GGO and fibrotic changes.

Objectives:

(1) To assess the relationship between 68 unique BAL proteins measured in participants of Scleroderma Lung Study (SLS) I1and radiographic and physiologic measures of ILD; (2) To identify inter-correlations among specific proteins to enlighten our understanding of how specific biological pathways contribute to SSc-ILD.

Methods:

Bronchoscopy was performed on 144 of the 158 participants in SLS I with 103 BAL samples available for analysis. BAL was lyophilized, concentrated 10X and used in a multiplex protein analysis for 68 different cytokines, chemokines and other factors. Kendall tau correlations were performed to assess the relationship between individual proteins and baseline measures of pulmonary function and quantitative CT scores for fibrosis, GGO and total ILD. Those proteins found to correlate significantly with at least 2 clinical measures of ILD were entered into a cluster analysis with inter-correlations expressed as a heatmap.

Results:

Significant correlations were observed between fibrosis scores and several biologic pathways including pro-fibrotic factors (transforming growth factor beta [TGF-β], platelet-derived growth factor [PDGF]), proteins involved in tissue remodeling (Matrix metallopeptidase [MMP]-1,7,8,9; Hepatocyte growth factor [HGF]), and those involved in monocyte/macrophage migration and activation (Monocyte chemoattractant protein [MCP]-1,3; macrophage colony-stimulating factor [MCSF]). These same pathways correlated with the diffusing capacity for carbon monoxide (DLCO). In contrast, GGO scores correlated primarily with immune and inflammatory mediators (interleukin [IL]-5,8,13,15, IL-1 receptor antagonist and interferon gamma) with only limited overlap to proteins that related to fibrosis. Vascular endothelial growth factor (VEGF) levels were lower in patients with more extensive GGO, fibrosis and diffusion impairment, suggesting that vascular changes are a central feature of SSc-ILD. Specific proteins were highly correlated with one another in a pattern suggesting biologically-related networks (Figure) that might provide additional insight regarding disease pathogenesis.

Conclusion:

Combining a diverse analysis of BAL proteins with the rich dataset available from SSc-ILD patients participating in SLS I, the study findings suggest the involvement of distinct biologic pathways, inter-related networks, and specific biologic signatures associated with unique radiographic features of ILD. The relationship of these factors to other SSc disease features, patient outcomes and as predictors of treatment responses will be studied in future analyses.

References:

[1]Tashkin DP, et al. NEJM 2006.

Figure.

Correlation heatmap of BAL proteins associated with at least 2 clinical measures of ILD in SSc patients. Absolute correlations are depicted, and darker colors signify stronger correlations.

Disclosure of Interests:

Elizabeth Volkmann Grant/research support from: Forbius, Corbus Pharmaceuticals, Consultant of: Boehringer Ingelheim, Forbius, Speakers bureau: Boehringer Ingelheim, Donald Tashkin: None declared, Ning Li: None declared, Grace Kim: None declared, Jonathan Goldin: None declared, Airi Harui: None declared, Michael Roth Grant/research support from: Genentech/Roche

Comparison of neutron and secondary gamma dose assessment using polygon mesh and voxel computational phantoms

The newly developed mesh-type reference computational phantoms (MRCPs) represent the evolution of the previous reference phantoms and a more detailed description of the human body, addressing the voxel reference phantom limitations. These allow for a more accurate dose calculation in the human body, which in some cases results in a significant difference of the calculated quantities. In this work, the absorbed dose calculation due to neutrons and gammas was calculated using a voxel and a mesh-type computational phantom. The goal was to understand how a more accurate description of the human body affects the estimated neutron dose. The phantoms were tested in a real-case scenario: they were placed in front of a neutron Howitzer container model using PHITS. This model corresponds to the neutron Howitzer container at the Neutron Measurements Laboratory of the Energy Engineering Department of the Polytechnic University of Madrid (UPM), and at the time of measurement it was equipped with a ²⁴¹Am-Be neutron source of 74 GBq in its center. The container allows the source to be in either the irradiation or the storage position. Results show that when dealing with neutrons, the dose deviation when using GOLEM or the MRCP leads to a general 20%-30% deviation that goes up to above 400% in small thin structures such as the eye.

1105 A Randomized Controlled Trial of a Psychological Intervention for Decreasing Bedtime Procrastination: The BED-PRO Study

Introduction

Bedtime Procrastination (BP) is defined as the behavior of going to bed later than intended, without having external reasons for doing so. Previous studies have shown that BP has a negative effect on sleep and health, and there is a need to develop interventions to decrease BP. This study (BED-PRO) is an ongoing study evaluating a behavioral intervention to reduce BP.

Methods

Fifteen participants who scored higher than 33 on the Bedtime Procrastination Scale were randomized to either the treatment (TRT, n=6) or control group (CTRL, n=9). Treatment consisted of four face-to-face individual sessions. All participants completed self-report questionnaires on Bedtime Procrastination Scale (BPS), Epworth Sleepiness Scale (ESS), Positive Affect and Negative Affect Schedule (K-PANAS-R) and completed the 7-day sleep diary. Data was analyzed using two-way mixed Measures Analysis of Variance (ANOVA).

Results

Mean age of the participants was 21.78 (±1.8) years and 80% (n=12) were females. Group by time interactions from repeated measures analyses revealed significant post intervention improvements in the TRT group compared to the CTRL group on all bedtime procrastination duration and scores, sleep efficiency, refreshment after waking, daytime sleepiness and negative affect of K-PANAS-R. Specifically, bedtime procrastination duration in the TRT group measured by sleep diaries decreased significantly from 75.30 (±58.57) min to 14.83 (±7.83) min, while the CTRL group did not change from 57.60 (±32.01) to 54.36 (±40.82) min (p=0.019). In addition, the TRT group reported significant improvements in bedtime procrastination scores from 36.00 (±4.05) to 22.50 (±6.72).

Conclusion

Based on results, the behavioral intervention used in this study looks promising in improving bedtime procrastination and sleep.

Support

This work was supported by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea(NRF-2018S1A5A8026807)