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Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): Hospital university of Rennes INSERM - LTSI Background Non-invasive estimation of myocardial work by trans-thoracic echocardiography is a novel tool to analyze myocardial contraction efficiency during systole. Two methods are described, on using Left ventricular (LV) strain and a LV pressure estimation, and another with only LV strain integrals. The present study analyzes their utility in prediction of CRT-response. Methods and results: 243 patients implanted by a CRT according to current recommendations were retrospectively included in hospital university of Rennes. All patients had a complete trans-thoracic echocardiography at implantation and at 6-moths follow-up. Responders were defined as having a 15% decrease in indexed LV end-systolic volume at follow-up compared to baseline. Baseline characteristics are described in table 1. 25.1% were non-responders. In this group, there were more men, more ischemic cardiomyopathies with more dilated LV. Strain signals ware analyzed only in the most informative loop, the apical 4 cavities. Myocardial work estimation with LV pressure estimation was previously described. The 3 different integral of strain signal were represented in figure 1. According to ROC curves, myocardial work (particularly wasted work in septal wall with AUC = 0.718 ± 0.04) estimated with LV pressure estimation is better than strain integrals to predict LV positive remodeling (best AUC 0.631 ± 0.040) after CRT-implantation. Conclusion Left ventricular pressure estimation give useful information on top of strain curves for prediction for CRT-response. Table 1 Responders n = 182 Non-responders n = 61 Men (%) 109 (59.9%) 52 (85%) Ischemic cardiomyopathy (%) 42 (23.1%) 34 (55.7%) LVEF (%) 28 ± 6 28 ± 7 GLS (%) -9 ± 3 -7 ± 3 LVEDD (mm) 62 ± 8 67 ± 7 LVEDVi (ml/m2) 85 ± 34 88 ± 30 LVEF Left ventricular ejection fraction; GLS: global longitudinal strain; LVEDD: left ventricular end-diastolic diameter; LVEDVi: left ventricular end diastolic volume index Abstract Figure 1

International audience; Introduction Variability of arterial blood pressure (ABP) has been associated with intraventricular hemorrhage in very preterm neonates (VPT) and may predict other brain lesions assessed at term-equivalent of age (TEA). Methods This was a prospective single-center study including VPT with early invasive continuous ABP monitoring and assessed at TEA using brain magnetic resonance imaging (TEA-MRI). The association between early mean ABP (MABP) and TEA-MRI findings was modeled by multivariate logistic regression analysis using covariates selected by the LASSO method. Results Among 99 VPT, the LASSO procedure selected consecutive periods of lowest MABP of 30 min on day 1 (d1) and 10 min on day 2 (d2) as the most relevant durations to predict TEA-MRI findings (OR [95% CI], 1.11 [1.02-1.23], p = 0.03 and 1.13 [1.01-1.27], p = 0.03, respectively). ROC curve analysis showed optimal thresholds at 30.25 mmHg on d1 and 33.25 mmHg on d2. This significant association persisted after adjustment with covariates including birthweight, gestational age, sex, and inotrope exposure. Final models selected by LASSO included the decile of the birthweight and lowest MABP for 30 min on d1 and 10 min on d2, for which the areas under the ROC curve were 74% and 75%, respectively. Conclusion Early continuous ABP monitoring may predict brain TEA-MRI findings in VPT. Impact Early arterial blood pressure monitoring may contribute to predicting brain damage upon MRI at term-equivalent of age for infants born very preterm. Careful blood pressure continuous monitoring in very preterm infants may identify infants at risk of long-term brain damage. Umbilical artery catheterization provides the best option for continuously monitoring arterial blood pressure in very preterm infants.

Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): ANR - Maestro project Background Stratification of aortic stenosis patients remains challenging and robust indices are required. Myocardial work assessment is a new afterload independent alternative to evaluate left ventricular function. Although, this method was developed in patients with normal aortic valve. We previously developed an integrated cardiovascular system simulated by a computational model to estimate non-invasively myocardial work in aortic stenosis patients* (figure 1A). In the present study, we tested our model in a prospective population of AS patients. Method and results 9 patients with severe AS (aortic valve area < 1cm2) were included. A complete trans-thoracic echocardiography with a non-invasive blood pressure by brachial artery cuff were realized immediately before a left heart catheterization to have an invasive left ventricular pressure. Myocardial work is then calculated with non-invasive and invasive LV pressure combined to LV strain curves. For constructive and wasted work, root mean squared between invasive and estimated measures were respectively r2 = 0.92 and r2 = 0.94 (figure 1B) Conclusion The proposed model is efficient to estimate non-invasively myocardial work indices in AS-patients. These afterload independent indices could permit in future to better stratify this population. *Owashi KP, Hubert A and al. Model-based estimation of left ventricular pressure and myocardial work in aortic stenosis. PlosOne 2020. Mar 3;15(3):e0229609 Abstract Figure 1

Funding Acknowledgements Type of funding sources: None. Objective The best modality to assess diastolic function in CRT-candidates is an object of debate and the relationship between diastolic function, CRT-response and survival are not clearly understood. Purpose of the study: to assess diastolic patterns in patients undergoing CRT according to the 2016 recommendations of the American Society of Echocardiography/European Association of Cardiovascular Imaging and to evaluate the prognostic value of diastolic dysfunction (DD) in CRT candidates. Methods 193 patients (age: 67 ± 11 years, QRS width: 167 ± 21 ms) were included in this multicentre prospective study. Patients were stratified according to DD grades (grade I to III). CRT-response was defined as a reduction of left ventricular (LV) end-systolic volume >15% at 6-month follow-up (FU). The primary endpoint was defined as a composite of heart transplantation, LV assisted device implantation or all-cause death during FU. Results During FU, 132 (68%) patients were CRT-responders. CRT delivery was associated with diastolic function degradation in non-responders. Grade I DD was able to predict CRT-response with a sensitivity, specificity and accuracy of 70%, 65%, and 63%, respectively. After a median period of 35 months, the primary endpoint occurred in 29 (15%) patients. Grade I DD was associated with a better outcome [HR 0.26 95% CI: (0.10-0.66)], independently from ischemic cardiomyopathy, LV dyssynchrony and CRT-response (Table 1). Non-responders with grade II or grade III DD had the worse prognosis (HR 4.36, 95%CI: 2.10-9.06) Figure 1. Conclusions Grade I DD is associated with LV remodelling after CRT and is an independent predictor of prognosis in CRT candidates. Abstract Figure.

Power systems exhibit nonlinear dynamics when load stress is high. Conventional linear wide-area controllers will fail in such scenarios, and instead nonlinear controllers will become necessary. This paper develops a state-feedback nonlinear quadratic controller based on perturbed Koopman mode analysis (PKMA) considering a sparse wide-area communication net-work for saving communication cost while guaranteeing closed-loop stability. The sparsity is decided based on the modal residues of the generators on selected nonlinear oscillations modes. The theoretical developments behind this sparse nonlinear control are first established, including the definition of residues for Koopman modes. Bilinear effects in the controller structure arising from quadratic PKMA-based extended models, structural constraints on the quadratic gain matrix design, and second-order phenomena in the closed-loop dynamics are all explained in detail. The design is validated using the IEEE 16-machine, 68-bus power system. The advantages and draw-backs of the proposed approach are illustrated using simulation results.

Aims Early diagnosis of heart failure with preserved ejection fraction (HFpEF) by determination of diastolic dysfunction is challenging. Strain–volume loop (SVL) is a new tool to analyse left ventricular function. We propose a new semi-automated method to calculate SVL area and explore the added value of this index for diastolic function assessment. Method and results Fifty patients (25 amyloidosis, 25 HFpEF) were included in the study and compared with 25 healthy control subjects. Left ventricular ejection fraction was preserved and similar between groups. Classical indices of diastolic function were pathological in HFpEF and amyloidosis groups with greater left atrial volume index, greater mitral average E/e’ ratio, faster tricuspid regurgitation (P Conclusion SVLs area is efficient to identify patients with a diastolic dysfunction. This new semi-automated tool is very promising for future development of automated diagnosis with machine-learning algorithms.

International audience; Dear editors, we read with a great interest the Brief Communication entitled “Acoustic stimulation time-locked to the beginning of sleep apnea events reduces oxygen desaturations: a pilot-study”, by Waeber et al.

Background Early diagnosis of heart failure with preserved ejection fraction (HFpEF) by determination of diastolic dysfunction is challenging. Strain-volume loop (SVL) is a new tool to analyze left ventricular function. Purpose We propose a new semi-automated method to calculate SVL area and explore the added value of this index for diastolic function assessment. Methods 50 patients (25 amyloidosis, 25 HFpEF) were included in the study and compared with 25 healthy control subjects. All patients underwent standard echocardiography. SVL area were also assessed. Results Left ventricular ejection fraction was preserved and similar between groups. Classical indices of diastolic function were pathological in HFpEF and amyloidosis groups with greater left atrial volume index, greater mitral average E/e' ratio, faster tricuspid regurgitation (p Conclusion Strain-volume loops area is efficient to identify patients with a diastolic dysfunction. This new semi-automated tool is very promising for future development of automated diagnosis with machine-learning algorithms. Figure 1 Funding Acknowledgement Type of funding source: None

Background Although patients with typical left bundle branch block (LBBB) show greater efficacy of cardiac resynchronization therapy (CRT), there is a wide range of responses to CRT with a subset of patients showing little or no improvement. Recently, it has been shown that combination of echo-based parameters of LV dyssynchrony and QRS duration helped to improve the prediction of the response to CRT. However, the interpretation of features extracted from echocardiography could be difficult due the complexity of mechanisms involved in cardiac contraction. Computational modelling could help to improve the interpretation of myocardial strains in LBBB patients before implantation. Purpose Purpose of the study is to propose a patient-specific model-based approach in order to assist the analysis of myocardial strains and to improve the interpretability of echo-based parameters. Methods The proposed model of the cardiovascular system integrates four main sub-models: 1) cardiac electrical system, 2) right and left atrium, 3) multi-segment right and left ventricles and 4) systemic and pulmonary circulations. Patient-specific simulations of myocardial strains were obtained by coupling the computational model and the clinical data to a parameter identification algorithm (Figure 1, upper panel). The proposed approach was evaluated on data obtained from 10 LBBB patients, including ischaemic (n=5) and non-ischaemic (n=5) cardiomyopathy. The localisation of scar was determined by cardiac MRI. Bull's-eye representations of the electrical activation time and contractility levels were analysed. Results The comparison between simulated and experimental strains for the 10 subjects reflects a satisfying adaptation of the model to different strain morphologies. The mean errors between real and synthesized signals are equal to 3.72±0.91. The lower panel of Figure 1 presents simulated (black line) and experimental (red line) myocardial strain signals for selected LBBB patients with a lateral ischaemia, anterior ischaemia and non-ischaemia. The bull's-eye representations of electrical activation delay and contractility levels, estimated from the model-based approach, for ischemic and non-ischemic LBBB is included in the figure. Contractility bull's-eye results allow ischaemic and non-ischaemic cases distinction, where low levels of contractility could be associated with damaged tissues. Conclusion Identified parameters show significant electrical conduction, mechanical activation delays for the LBBB patient. Hypocontractile myocardial segments were successfully localized from the model-based approach in both ischemic and non-ischemic patients. Funding Acknowledgement Type of funding source: None

Background The relationship between diastolic dysfunction (DD) and outcome after CRT is debated. Purpose Purpose of this study was to evaluate the role of DD in predicting all-cause mortality in heart failure patients undergoing CRT. Methods One-hundred ninety-three patients (age: 67±11 years, QRS width: 167±21 ms, LVEF 28±8%) were included in this multicentre prospective study. Mitral filling pattern, mitral tissue Doppler velocity, tricuspid regurgitation velocity, and indexed left atrial volume were used to classify DD from grade I to III according to the 2016 recommendations of the American Society of Echocardiography/European Association of Cardiovascular Imaging. A reduction of LV end-systolic volume >15% at 6-month follow-up (FU) identified CRT-responders and was observed in 132 (68%) patients. Results During a median 35 months FU, 29 (15%) patients died. Through multivariable analysis, coronary artery disease, NYHA functional class and grade I DD were shown to be independent predictors of prognosis (Table 1). Grade I DD was associated with a longer survival rate in both responders and non responders (Figure 1). Non responders with grade II-III DD had the worse outcome (HR 12.5 [3.56–44.04], p Conclusions Better diastolic function at baseline is associated with an improved survival after CRT implantation, independently of CRT-response. Funding Acknowledgement Type of funding source: None

The corrosion behavior of pure aluminum (Al) in 20 v/v% ethanol&ndash, gasoline blends has been studied using electrochemical techniques. Ethanol was obtained from different fruits including sugar cane, oranges, apples, or mangos, whereas other techniques included lineal polarization resistance, electrochemical noise, and electrochemical impedance spectroscopy for 90 days. Results have shown that corrosion rates for Al in all the blends were higher than that obtained in gasoline. In addition, the highest corrosion rate was obtained in the blend containing ethanol obtained from sugar cane. The corrosion process was under charge transfer control in all blends, however, for some exposure times, it was under the adsorption/desorption control of an intermediate compound. Al was susceptible to a localized, plotting type of corrosion in all blends, but they were bigger in size and in number in the blend containing ethanol obtained from sugar cane.

International audience; This paper proposes a patient-specific model-based estimation of myocardial strain signals and the evaluation of echo-based parameters, adapted to patients with left bundle branch block (LBBB). The left ventricle (LV) was divided into 16 segments in order to evaluate concurrently different regions at the ventricular contraction process. For each LV segment, some parameters, associated with the active and passive components of the cardiac muscle, the electro-mechanical driving function and the electrical depolarization time, were identified using evolutionnary algorithms. The proposed approach was evaluated on data obtained from 3 LBBB patients. From patient-specific simulations, we also analysed electrical activation delay and myofiber contractility in LV segments. A close match was observed between experimental and simulated myocardial strain curves for all the subjects. The root mean square error (RMSE) is equal to 2.87(± 1.00), 2.49(± 0.55) and 3.63(± 0.81) for the anterior ischemic, the lateral ischemic and the non-ischemic LBBB patients, respectively. The proposed patient-specific model-based approach may be a useful tool for understanding LV mechanical dyssynchrony and identifying patients suitable for cardiac resynchronization therapy (CRT). © 2020 Creative Commons; the authors hold their copyright.

International audience; Significant cardio-respiratory fluctuations are often observed during and after an epileptic seizure event. The mechanisms underlying these acute modifications are considered to be involved in sudden and unexpected death in epilepsy (SUDEP). We hypothesize that these acute events are mediated by specific dynamics of the autonomic nervous system (ANS). However, the evaluation of the ANS during seizures remains particularly challenging, mainly due to the lack of observability. Computational modelling could help to override these limitations, to assess ANS modulation and to evaluate this hypothesis. In this study, we propose and apply a recursive identification algorithm of a system-level model of the autonomic modulation of the sino-atrial node, integrating a Tikhonov regularization, in order to assess sympathetic and parasympathetic activities during ictal tachy-bradycardia events. We evaluate the feasibility of the method on heart rate (HR) data from 4 seizures observed in the same patient. After parameter optimization and identification we were able to reproduce observed HR data with a maximum root mean squared error equals to 1.7bpm. The estimated autonomic series show sympathetic activation and parasympathetic inhibition at the seizure onset, and a massive vagal discharge as the leading factor to ictal bradycardia. © 2020 Creative Commons; the authors hold their copyright.

International audience; Conflicting data exist about the relationship between cardiac resynchronization therapy (CRT) and diastolic function. Aims of the study are to assess diastolic patterns in patients undergoing CRT according to the 2016 recommendations of the American Society of Echocardiography/European Association of Cardiovascular Imaging and to evaluate the prognostic value of diastolic dysfunction (DD) in CRT candidates. METHODS AND RESULTS: One-hundred ninety-three patients (age: 67 ± 11 years, QRS width: 167 ± 21 ms) were included in this multicentre prospective study. Mitral filling pattern, mitral tissue Doppler velocity, tricuspid regurgitation velocity, and indexed left atrial volume were used to classify DD from grade I to III. CRT-response, defined as a reduction of left ventricular (LV) end-systolic volume > 15% at 6-month follow-up (FU), occurred in 132 (68%) patients. The primary endpoint was a composite of heart transplantation, LV assisted device implantation, or all-cause death during FU and occurred in 29 (15%) patients. CRT was associated with a degradation of DD in non-responders. At multivariable analysis corrected for clinical variables, QRS duration, mitral regurgitation, CRT-response and LV dyssynchrony, grade I DD was associated with a better outcome (HR 0.37, 95% CI: 0.14-0.96). Non-responders with grade II-III DD had the worse prognosis (HR 4.36, 95%CI: 2.10-9.06). CONCLUSIONS: The evaluation of DD in CRT candidates allows the prognostic stratification of patients, independently from CRT-response.

International audience; Apnea-bradycardia (AB) is a common complication in prematurely born infants, which is associated with reduced survival and neurodevelopmental outcomes. Thus, early detection or predication of AB episodes is critical for initiating preventive interventions. To develop automatic real-time operating systems for early detection of AB, recent advances in signal processing can be employed. Hidden Markov Models (HMM) are probabilistic models with the ability of learning different dynamics of the real time-series such as clinical recordings. In this study, a hierarchy of HMMs named as layered HMM was presented to detect AB episodes from pre-processed single-channel Electrocardiography (ECG). For training the hierarchical structure, RR interval, and width of QRS complex were extracted from ECG as observations. The recordings of 32 premature infants with median 31.2 (29.7, 31.9) weeks of gestation were used for this study. The performance of the proposed layered HMM was evaluated in detecting AB. The best average accuracy of 97.14 +/- 0.31% with detection delay of - 5.05 +/- 0.41 s was achieved. The results show that layered structure can improve the performance of the detection system in early detecting of AB episodes. Such system can be incorporated for more robust long-term monitoring of preterm infants.

B.A. Hernández Umaña, the coauthor of the article, gratefully acknowledges the financial support provided by the following institutions: the University Santo Tomas – Colombia (Project reference 1811502-006-28022018). J.A. Rodríguez Martín, the corresponding author of the article, gratefully acknowledges the financial support provided by the following institutions: The Ministry of Economy, Industry, and Competitiveness of Spain; the State Research Agency (SRA); and European Regional Development Fund (ERDF) (project reference ECO2017-86822-R)., The article analyzes how approaches to “Living Well” as reflected in the Constitution of the State of Bolivia, the Law of the Rights of Mother Earth, and the American Declaration on the Rights of Indigenous Peoples of the Organization of American States (OAS) contribute to understanding the Andean cosmovision of indigenous peoples of the American continent. To do so, it first studied the most immediate precedents that led to incorporation of the notion of Living Well into Bolivian law. Second, it approached the right to development from the American Declaration on the Rights of Indigenous Peoples, which has as its source the United Nations Declaration of the Rights of Indigenous Peoples. The paper thus proposes reflections on the Bolivian State and the American Declaration that advance understanding of Living Well, a notion comparable in the West to the right to development (political, social, economic, environmental, and cultural) that enables the individual and collective realization of the individual. Fullness, understood in terms of well-being, is related to the protection of health and of the environment. Finally, the paper employs a qualitative methodology with a well-documented hermeneutic focus, as well as the tool of a semi-structured interview with a Bolivian scholar familiar on the topic., This research was partially funded by the Santo Tomas University, (Colombia), grant number 1811502-006-28022018, Communication for Good Living/Living Well in Latin America (AbyaYala). Towards a construction of intercultural dialogues. This research was partially funded by the Ministry of Economy, Industry and Competitiveness of Spain, the State Research Agency (SRA) and European Regional Development Fund (ERDF), grant number ECO2017-86822-R, Pro-environmental behavior and subjective well-being: towards sustainable development.

International audience; The objective of the current study was to propose a sensitivity analysis of a 3D left ventricle model in order to assess the influence of parameters on myocardial mechanical dispersion. A finite element model of LV electro-mechanical activity was proposed and a screening method was used to evaluate the sensitivity of model parameters on the standard deviation of time to peak strain. Results highlight the importance of propagation parameters associated with septal and lateral segments activation. Simulated curves were compared to myocardial strains, obtained from echocardiography of one healthy subject and one patient diagnosed with intraventricular dyssynchrony and coronary artery disease. Results show a close match between simulation and clinical strains and illustrate the model ability to reproduce myocardial strains in the context of intraventricular dyssynchrony.

Brugada syndrome (BS) is a genetic pathology that might cause sudden cardiac death (SCD) in patients with a structurally normal heart. Repolarization disorders have been postulated as a potential substrate for triggering cardiac arrhythmia in BS, that usually occur at rest or during sleep. In this paper, we have characterized ventricular repolarization markers during sleep on patients suffering from BS. To this end, standard 12-lead ECG recordings were analyzed in a population of 110 BS patients (25 symptomatic). The QT and the T-wave peak to T-wave end intervals (respectively QT and Tpe) were assessed from lead V5. The linear relationship between these markers and the instantaneous heart rate period (RR interval) are determined during each hour and for the whole sleep period. From the models obtained, corrected QT and Tpe measures were then estimated for each patient at 60 beats/min (QT 60 and Tpe 60 ) and at the mean heart rate observed during the involved time interval ($Q{T_{\overline {{\mathbf{HR}}} }}$ and $Tp{e_{\overline {{\mathbf{HR}}} }}$). Results show larger values for symptomatic patients in all markers, with significant differences with respect to the asymptomatic group in the case of Tpe (Tpe 60 : p = 0.0012; Tpe HR : p = 0.0014). Moreover, the temporal profiles of these markers reveal major differences among BS subgroups during the last 3 hours of sleep, where symptomatic patients presented increased QT 60/HR (p = 0.01) and T pe 60/HR (p < 0.001), as compared to the initial sleep hours. We conclude that BS patients present different repolarization properties according to their symptomatology, especially during the final stage of sleep.

What drives world leaders to act in good faith or in defiance of the norms that underpin sovereign lending? I propose an analytic framework to study the impact of economic narratives on emerging-market stances towards the international regime for sovereign debt. Latin American leaders draw on two narratives of the global political-economy: a) one which characterizes the market-mechanisms-based financial system as a zero-sum game which perpetuates economic hierarchies, and b) one which stresses its developmental potential and characterizes it as a positive-sum game. I employ Computational Text Analysis (CTA) methods to measure how often the topic of international finance has been discussed in United Nations General Assembly (UNGA) speeches (1970-2018) and how it has been framed. I explore two paradigmatic cases from Latin America where a pro-active foreign economic policy was pursued informed by opposing economic narratives. The first is Mexico's promotion of market mechanisms to reform the international financial architecture under Vicente Fox with the diffusion of Collective Action Clauses and the 2002 Monterrey Consensus. The second considers the politically motivated 2008 Ecuadorian default and Rafael Correa's denunciation of international financiers.

Aims. We hypothesized that a multiparametric evaluation, based on the combination of electrocardiographic and echocardiographic parameters, could enhance the appraisal of the likelihood of reverse remodeling and prognosis of favorable clinical evolution after cardiac resynchronization therapy (CRT). Also, we sought to test the respective value of automatically extracted parameters from left ventricular (LV) strain curves recorded in apical 4-chamber view as compared to the other echocardiographic views. Methods and results; This is a machine learning study based on a dataset of 161 patients who were treated by CRT according to current ESC-guidelines. The longitudinal strain curves of the 6 LV-segments of the left ventricle were plot for the three different apical views. Several features as times or integrals were extracted as previously published. These features were classified by importance using the out-of-bag method(fig1). Half of the most important features come from the 4-chamber view and a third from the 2-chamber view. The correlation between the most important features was studied to determine the relationship between them. Almost all the features from the 2-chamber and apical long-axis views are correlated with others and generally with one acquired from the 4-chamber view. Conclusion The high number of important features indicate the relevance of the 4-chamber as unique view for applying machine learning approaches on strain curves. Optimizing selection of patients for CRT should be possible just on the dataset coming from one apical 4-chamber view. Abstract 539 Figure. fig1

Background The noninvasive assessment of myocardial work by pressure-strain loops (PSL) analysis is a recently introduced tool to estimate myocardial performance. PSL analysis cannot be applied to patients having an obstacle to LV ejection, as in the case of aortic stenosis (AS), because of the difficulty to estimate left ventricular (LV) pressure. The purpose of this work is to propose a non-invasive model-based estimation of the left ventricular pressure curve in AS patients in order to evaluate myocardial work indices. Methods Twelve patients with moderate-to-severe AS underwent cardiac catheterization to acquire the LV pressure (Pexp-LV). All patients underwent a standard trans-thoracic echocardiography to extract regional myocardial strain curves and estimate the aortic valve area (AVA). Systolic and diastolic arterial pressures were also measured. The proposed cardiovascular system (CVS) model is composed of four main coupled sub-models simulating: i) cardiac electrical activities, ii) cardiac cavity, iii) the systemic and pulmonary circulation, and iv) cardiac valves (Figure 1, upper panel). A 2-step parameter identification strategy, based evolutionary algorithms, was implemented to learn LV parameters from Pexp-LV and to estimate patient-specific model-based LV pressure curves (Pmodel-LV) starting from parameters obtained from non-invasive hemodynamics. Global myocardial constructive work (GCW) and myocardial wasted work (GWW) were calculated using Pexp-LV and Pmodel-LV. Results A close match was observed between Pexp-LV and Pmodel-LV, with a mean total relative error of 12.27% (range 5.9% to 17.40%). When considering GCW and GWW, global correlation was equal to 0.92 (p Conclusions A model-based approach can be used to estimate LV pressure and myocardial work indices in patients with AS, and be provide a promising tool for the assessment of myocardial performance in patients with AS Funding Acknowledgement Type of funding source: None

Sin resumen

International audience; Purpose - The area of left ventricular (LV) pressure-strain loop (PSL) is used as an index of regional myocardial work. The purpose of the present work is to compare the main segmental PSL markers and the derived global work indices, when they are calculated using an estimated pressure signal or an observed pressure signal.Methods and results - In nine patients implanted with a bi-ventricular pace-maker (CRT), LV pressure was invasively measured in five conditions: CRT-off, LV-pacing, right ventricular-pacing and two different CRT-pacing. For each condition, systolic blood pressure was measured by brachial artery cuff-pressure and transthoracic echocardiography loops were recorded simultaneously. The error and relative root mean square error (rRMSE) between measured and estimated pressure were calculated for each patient and each configuration. Correlation coefficient (R2) and Bland-Altman (BA) analysis were performed for PSL area and work indices. A total of 43 different haemodynamic conditions were compared (774 segmental PSL). The global rRMSE between estimated and measured LV-pressure was 12.3 mmHg. The estimated and measured segmental LV-PSL were strongly correlated, with an R2 of 0.98. BA analysis shows that the mean bias for the estimation of segmental LV-PSL area is 86.0 mmHg.%. A significant bias effect with linearly increasing error with pressure values is observed. R2 ≥ 0.88 and a mean bias in BA analysis ≤41.4 mmHg.% was observed for the estimation of global myocardial work indices.Conclusion - The non-invasive estimation for LV pressure-strain loop area and the global myocardial work indices obtained from LV-PSL strongly correlates with invasive measurements.

International audience; Background - Cardiac resynchronization therapy (CRT) in heart failure is plagued by too many nonresponders. The aim of the present study is to evaluate whether the estimation of myocardial performance by pressure-strain loops (PSLs) is useful for the selection of CRT candidates.Methods - Ninety-seven patients undergoing CRT were included in the study. Bidimensional and speckle-tracking echocardiography were performed before CRT and at the 6-month follow-up (FU). Conventional dyssynchrony parameters were evaluated. Left ventricular (LV) constructive work (CW) and wasted work (WW) were estimated by PSLs. Positive response to CRT (CRT+) was defined as ≥15% reduction in LV end-systolic volume at FU and was observed in 63 (65%) patients.Results - The addition of CW > 1,057 mm Hg% (area under the curve, 0.72, P 384 mm Hg% (area under the curve, 0.67, P = .005) to a baseline model including clinical, echocardiographic, and conventional dyssynchrony parameters significantly increased the model power (χ, 25.11 vs 47.5, P 1,057 mm Hg% (OR = 9.49; P = .002), and WW > 384 mm Hg% (OR = 16.24, P 1,057 mm Hg% and WW > 384 mm Hg% showed a good specificity (100%) and positive predictive value (100%) but a low sensitivity (22%), negative predictive value (41%), and accuracy (49%) for the identification of CRT+.Conclusions - The estimation of CW and WW by PSLs is a novel tool for the assessment of CRT patients. Although these parameters cannot be used by their own to select CRT candidates, they can provide further insights into the comprehension of dyssynchrony mechanisms and contribute to improving the identification of CRT responders.

Background The relationship between diastolic dysfunction (DD) and outcome after CRT is debated. The purpose of this study was to evaluate the role of DD in predicting all-cause mortality in heart failure patients undergoing CRT. Methods One-hundred ninety-three patients (age: 67 ± 11 years, QRS width: 167 ± 21 ms, LVEF 28 ± 8%) were included in this multicentre prospective study. Mitral filling pattern, mitral tissue Doppler velocity, tricuspid regurgitation velocity, and indexed left atrial volume were used to classify DD from grade I to III according to the 2016 recommendations of the American Society of Echocardiography/European Association of Cardiovascular Imaging. A reduction of LV end-systolic volume > 15% at 6-month follow-up (FU) identified CRT-responders and was observed in 132 (68%) patients. Results During a median 35 months FU, 29 (15%) patients died. Through multivariable analysis, coronary artery disease [HR 2.21 (1.00–4.89) P = 0.05], NYHA [HR 2.92 (1.45–5.87), P = 0.003] and grade I DD [HR 0.34 (0.13–0.89)] were shown to be independent predictors of prognosis ( Table 1 ). Grade I DD was associated with a longer survival rate in both responders and non-responders ( Fig. 1 ). Non-responders with grade II-III DD had the worse outcome [HR 12.5 (3.56–44.04), P Conclusion Better diastolic function at baseline is associated with improved survival after CRT implantation, independently of CRT-response.

Background Non-invasive estimation of myocardial work by transthoracic echocardiography is a novel tool to analyse myocardial contraction efficiency during systole. Two methods are described, on using Left ventricular (LV) strain and a LV pressure estimation, and another with only LV strain integrals. The present study analyses their utility in prediction of CRT-response. Methods and results In total, 243 patients implanted by a CRT according to current recommendations were retrospectively included in hospital university of Rennes. All patients had a complete transthoracic echocardiography at implantation and at 6-moths follow-up. Responders were defined as having a 15% decrease in indexed LV end-systolic volume at follow-up compared to baseline. Baseline characteristics are described in Table 1 ; 25.1% were non-responders. In this group, there were more men, more ischemic cardiomyopathies with more dilated LV. Strain signals were analysed only in the most informative loop, the apical 4 cavities. Myocardial work estimation with LV pressure estimation was previously described. The 3 different integral of strain signal were represented in Fig. 1 . According to ROC curves, myocardial work (particularly wasted work in septal wall with AUC = 0.718 ± 0.04) estimated with LV pressure estimation is better than strain integrals to predict LV positive remodelling (best AUC 0.631 ± 0.040) after CRT-implantation. Conclusion Left ventricular pressure estimation give useful information on top of strain curves for prediction for CRT-response.

Background Patients undergoing cardiac resynchronisation therapy are heterogeneous. Therefore, the prediction of CRT-response and outcome is challenging. The aim of this study was to evaluate the relative impact of clinical, electrocardiographic, and echocardiographic variables on the left ventricular (LV) remodelling and prognosis of CRT-candidates by the application of machine-learning (ML) approaches. Methods In total, 193 patients undergoing CRT (mean age 67 ± 11 years, QRS width: 167 ± 21 msec) were prospectively included in this multicentre study. We used a combination of the Boruta algorithm and random forest methods (RF) to identify features predicting both CRT-volumetric response and prognosis. The model performance was tested by the area under the receiver-operating curve (AUC). We also applied the K-medoid method to identify clusters of phenotipically-similar patients. Results From 28 clinical, electrocardiographic, and echocardiographic-derived variables, 16 features were predictive of CRT-response, and 11 features were predictive of prognosis. Among the predictors of CRT-response, 6 variables (38%) pertained to right ventricular (RV) size or function. The tricuspid annular plane systolic excursion was the main feature associated with prognosis. The selected features were associated with a very good prediction of both CRT-response (AUC: 0.81, 95% CI: 0.74–0.87) and outcome (AUC 0.84, 95% CI: 0.75–0.93) ( Fig. 1 A–B). An unsupervised ML approach allowed the identifications of two phenogroups of patients who differed significantly in clinical parameters, biventricular size and RV function and had significantly different prognosis (log-rank P Table 1 ). Conclusions ML can reliably identify clinical and echocardiographic features associated with CRT-response and prognosis. Our results underscore the value of the assessment of RV-size and function parameters for the risk stratification of CRT-candidates.

Vapor phase infiltration (VPI) is a bottom-up process that involves the infiltration of polymers, often using atomic layer deposition compatible precursors. By exposing a polymer to an organo-metallic precursor, area selective material formation is achieved where the precursor reacts with regions covered by an infiltration-receptive polymer brush. Combining receptive and rejecting polymers that have the capability of forming complex nanopatterns could potentially allow for the creation of nanofeatures, offering a route to area selective deposition. This work is concerned with the creation and characterization of titanium-infiltrated films with a VPI process. Thin films of poly(methyl methacrylate) (PMMA) were infused with titanium isopropoxide and subsequently analyzed with angular resolved x-ray photoelectron spectroscopy. All XPS analysis and VPI treatments were completed without breaking vacuum in an integrated ultrahigh vacuum setup, with O 1s, C 1s, Ti 2p, and Si 2p core levels revealing the successful incorporation of titanium into the polymer. Grazing angle Fourier-transform infrared spectroscopy demonstrates the breaking of carbon–oxygen double bonds within the PMMA structure due to titanium incorporation.

"Our objective was to assess the quality of eggs and juvenile of Nile tilapia ( Oreochromis niloticus ) from broodstock of three commercial hatcheries (H1, H2, and H3). Larval weight was significantly higher for H2 and H3 hatcheries ( P < 0.05) . After 45 - day growth, weight of juveniles of H2 was higher, while specific growth rate was significantly higher fo r H1 and H2 ( P < 0.05) . A fter the ammonia stress test, n o significant differences in mortality were found among larvae from the three hatcheries, although a positive relationship between carbohydrate content in eggs and juvenile mortality was observed ( P < 0.05) . After the salinity stress test, the lowest and highest mortality ( P < 0.05 ) occurred respectively in tilapia larvae from the H1 (24.2%) and H3 (57.8%) hatcheries. We concluded that egg quality was not affected by tilapia broodstock from the three h atcheries studied, but differences were obtained for growth performance, carbohydrate content, and survival of juveniles when exposed to the salinity stress test. These three indexes should be considered as potential juvenile quality criteria for tilapia."

International audience; AIM: This study examined the heart rate variability characteristics associated with early-onset neonatal sepsis in a prospective, observational controlled study.METHODS: Eligible patients were full-term neonates hospitalised with clinical signs that suggested early-onset sepsis and a C-reactive protein of >10 mg/L. Sepsis was considered proven in cases of symptomatic septicaemia, meningitis, pneumonia or enterocolitis. Heart rate variability parameters (n = 16) were assessed from five-, 15- and 30-minute stationary sequences automatically selected from electrocardiographic recordings performed at admission and compared with a control group using the U-test with post hoc Benjamini-Yekutieli correction. Stationary sequences corresponded to the periods with the lowest changes of heart rate variability over time.RESULTS: A total of 40 full-term infants were enrolled, including 14 with proven sepsis. The mean duration of the cardiac cycle length was lower in the proven sepsis group than in the control group (n = 11), without other significant changes in heart rate variability parameters. These durations, measured in five-minute stationary periods, were 406 (367-433) ms in proven sepsis group versus 507 (463-522) ms in the control group (p < 0.05).CONCLUSION: Early-onset neonatal sepsis was associated with a high mean heart rate measured during automatically selected stationary periods.

Background: Inflammatory adhesions result from an inflammatory response of the peritoneum during an intra-abdominal inflammatory process secondary to thermal or mechanical injury, infection, radiation, ischemia, dissection, abrasion or foreign body reaction. Adhesions produce consequences such as: infertility, intestinal obstruction, and pelvic-abdominal pain. The objective of this study is to evaluate the effects of Meloxicam, a selective cyclooxygenase-2 inhibitor, on the formation of postoperative peritoneal adhesions in an experimental animal model. Methods: Twenty female Wistar rats were submitted to laparotomy. Postoperative peritoneal adhesions were induced by scorching the serous surface of the colon. The animals were randomly divided into two experimental groups: one group received Meloxicam intramuscularly for 7 days, and the other served as a control group. They were sacrificed and evaluated at 15 days. Results: In the animals given Meloxicam, it was observed that a decrease in number (p = 0.018), severity (p = 0.004), extension (p = 0.011), density (p = 0.023), degree of inflammation (p = 0.002), vascular proliferation (p = 0.004) and fibrosis (p = 0.029) of adhesions, compared to the control group. Conclusion: In conclusion, this study demonstrated that the administration of Meloxicam intramuscularly significantly decreases the formation of postoperative peritoneal adhesions and, therefore, may be useful in their prevention. The effects of Meloxicam could not only be due to its anti-inflammatory action, but also to its effects on the expression of the Vascular Endothelial Growth Factor.

International audience; Aims: Assessment of left ventricular (LV) volumes and ejection fraction (LVEF) with cardiac imaging is important in the selection of patients for cardiac resynchronization therapy (CRT). Several observational studies have explored the role of imaging-derived LV dyssynchrony parameters to predict the response to CRT, but have yielded inconsistent results, precluding the inclusion of imaging-derived LV dyssynchrony parameters in current guidelines for selection of patients for CRT. Methods: The EuroCRT is a large European multicentre prospective observational study led by the European Association of Cardiovascular Imaging. We aim to explore if combing the value of cardiac magnetic resonance (CMR) and echocardiography could be beneficial for selecting heart failure patients for CRT in terms of improvement in long-term survival, clinical symptoms, LV function, and volumes. Speckle tracking echocardiography will be used to assess LV dyssynchrony and wasted cardiac work whereas myocardial scar will be assessed with late gadolinium contrast enhanced CMR. All data will be measured in core laboratories. The study will be conducted in European centres with known expertise in both CRT and multimodality cardiac imaging.

Symptoms such as ventricular arrhythmias in Brugada syndrome (BS) typically occur at rest, especially during sleep, suggesting that the autonomic nervous system (ANS) function may be relevant in the arrhythmogenesis of the disease. The aim of this work was to assess the ANS response captured by a non-linear heart rate variability (HRV) measure in 69 patients diagnosed with BS, who underwent a standardized physical stress test. Heart rate complexity (HRC) was evaluated by the power-law scaling analysis (Beta slope) during rest, exercise, recovery and rest post-recovery, in order to discriminate between symptomatic and asymptomatic BS patients. Symptomatic patients showed a significant reduction in HRC in comparison to asymptomatic subjects, after exertion (p=0.015); during the whole recovery period (p=0.023), and, in particular within the passive recovery phase (p=0.025), as well as during rest post-recovery (p=0.022). Based on these results, symptoms could be associated with a lower ANS complexity during the stress test stages where parasympathetic activity is predominant. Therefore, the proposed HRV indicators could be of help in the risk stratification of asymptomatic patients.

Aim This work aims to evaluate a novel semi-automatic tool for the assessment of volume-strain loops by transthoracic echocardiography (TTE). The proposed method was evaluated on a typical model of left ventricular (LV) diastolic dysfunction: the cardiac amyloidosis. Method 18 patients with proved cardiac amyloidosis were compared to 19 controls, from a local database. All TTE were performed using Vivid E9 or E95 ultrasound system. The complete method includes several steps: 1) extraction of LV strain full traces from apical 4 and 2 cavities views, 2) estimation of LV volume from these two traces by spline interpolations, 3) resampling of LV strain curves, determined for the same cardiac beat, (in apical 4-, 2- and 3- cavities views) as a function of pre-defined percentage increments of LV-volume and 4) calculation of the LV volume-strain loop area. (Figure 1, panel B) Results (Table 1): LVEF was similar between both groups whereas global longitudinal strain was significantly lower in amyloidosis group (−14.4 vs −20.5%; p Table 1 Amyloidosis (N=18) Controls (N=19) p Global strain-volume loop area (%.mL) 36.5±21.3 120.0±54.2 Figure 1 Conclusion LV volume-strain loop area appears a very promising new tool to assess semi-automatically diastolic function. Future applications will concern the integration of LV volume-strain loop area as novel feature in machine-learning approach.

The present study aimed to further unravel the effects of nasal continuous positive airway pressure (nCPAP) on the cardiovascular and respiratory systems in the neonatal period. Six-hour polysomnographic recordings were first performed in seven healthy newborn lambs, aged 2–3 days, without and with nCPAP application at 6 cmH2O (nCPAP-6), in randomized order. The effects of nCPAP-6 on heart rate variability, respiratory rate variability, and cardiorespiratory interrelations were analyzed using a semiautomatic signal processing approach applied to ECG and respiration recordings. Thereafter, a cardiorespiratory mathematical model was adapted to the experimental conditions to gain further physiological interpretation and to simulate higher nCPAP levels (8 and 10 cmH2O). Results from the signal processing approach suggest that nCPAP-6 applied in newborns with healthy lungs: 1) increases heart rate and decreases the time and frequency domain indices of heart rate variability, especially those representing parasympathetic activity, while increasing the complexity of the RR-interval time series; 2) prolongs the respiratory cycle and expiration duration and decreases respiratory rate variability; and 3) slightly impairs cardiorespiratory interrelations. Model-based analysis revealed that nCPAP-6 increases the heart rate and decreases respiratory sinus arrhythmia amplitude, in association with a reduced parasympathetic efferent activity. These results were accentuated when simulating an increased CPAP level. Overall, our results provide a further understanding of the effects of nCPAP in neonates, in the absence of lung disease.NEW & NOTEWORTHY Application of nasal continuous positive airway pressure (CPAP) at 6 cmH2O, a level very frequently used in newborns, alters heart and respiratory rate variability, as well as cardiorespiratory interrelations in a full-term newborn model without lung disease. Moreover, whereas nasal CPAP at 6 cmH2O decreases parasympathetic efferent activity, there is no change in sympathetic efferent activity.

Neural conduction block performed by balanced-charge kilohertz frequency alternating currents (KHFAC) has been identified as a potential technique for therapy delivery in different clinical setups. The underlying mechanisms that contribute to this phenomenon have been studied through computational models and animal experiments. However, the optimal stimulation parameters to achieve axonal conduction block are difficult to define, since they depend on the species, the nerve being targeted, as well as the technical and experimental setup. This study proposes an experimental setup along with an original data processing approach for the quantification of the effectiveness of neural conduction block. Experiments were performed on the sciatic nerve of two Sprague-Dawley rats, by evaluating different groups of stimulation parameters with varying amplitudes and frequencies, ranging from 1 to 10 mA and from 2 to 10 kHz, respectively. Results suggest that the effectiveness of axonal conduction block strongly depends on the selection of the stimulation parameters. In this work, more effective blockages were achieved for frequencies around 4 kHz and within an approximate amplitude range of 2 to 8 mA.

El objetivo principal de este artículo es analizar la Declaración Americana sobre los Derechos de los Pueblos Indígenas, partiendo de las novedades que esta Declaración tuvo en su creación. En este marco, se consideran las diferentes miradas y comprensiones acerca del Buen Vivir/Vivir Bien Andino, para abordar, a partir de la des/colonialidad de los derechos humanos, las ausencias que se echaron en falta en la Declaración, respecto al derecho al desarrollo. Finalmente, se presentan algunas reflexiones, que pueden orientar la discusión y el reconocimiento de la pluridiversidad entre los pueblos del continente americano. The main aim of this article is to analyze the American Declaration on the Rights of Indigenous Peoples, based on the novelties that this Declaration had in its creation. Then we consider the different views and understandings about the Andean Good Living/Living Well, to address, from the de/coloniality of Human Rights, the absences that were lacking in the Declaration, related to the development right. Eventually, we present some thoughts, which can guide the discussion and the recognition of the pluridiversity among the peoples of the American Continent.

International audience; Background - Recent studies have shown that myocardial constructive work (CW) assessed by pressure-strain loops (PSLs) is an independent predictor of a volumetric response to cardiac resynchronization therapy (CRT). The aim of this study was to evaluate the role of CW in predicting the cardiac outcome of heart failure patients undergoing CRT. Methods - This is a retrospective study including 166 CRT candidates (ejection fraction [EF] ≤35%, QRS duration ≥120 milliseconds). Two-dimensional standard echocardiography and speckle-tracking echocardiography were performed before CRT and at 6-month follow-up. PSLs were used to assess myocardial CW. Results - After a median follow-up of 4 years (range 1.3-5 years), cardiac death occurred in 14 patients (8%). A multivariable Cox regression analysis including age, coronary artery disease, and septal flash showed that CW≤888 mm Hg% was the only independent predictor of cardiac mortality (hazard ratio 4.23, 95% CI 1.08-16.5, P = .03). After 6 months of CRT, a 15% reduction in left ventricular end-systolic volume was observed in 118 (71%) patients, and a CRT volumetric response was identified. Among CRT responders, the concomitant presence of CW ≤888 mm Hg% identified a subgroup of patients at high risk of cardiac death (P = .04 in the log-rank test). The addition of CW ≤888 mm Hg% to a model including age, coronary artery disease, septal flash, and CRT response caused a significant increase in model power for the prediction of cardiac death (χ: 12.6 vs 25.7, P = .02). Conclusions - The estimation of left ventricular CW by PSLs is a relatively novel tool that allows for the prediction of cardiac outcome in CRT candidates.

International audience; Simulating the response to radiotherapy (RT) in cancer patients may help devising new therapeutic strategies. Computational models make it possible to cope with the multi-scale biological mechanisms characterising this group of diseases. We present in this paper an in silico model of tumour growth and radiation response, capable of simulating a whole RT protocol of prostate cancer. Oxygen diffusion, proliferation of tumour cells, angiogenesis based on the VEGF diffusion, oxygen-dependent response to irradiation and resorption of dead cells were implemented in a multi-scale framework. A sensitivity analysis using the Morris screening method was performed on 21 computational tissues, initialised from prostate histopathological specimens presenting different tumour and vascular densities. The dose per fraction and the duration of the cycle of tumour cells were identified as the most important parameters of the model.

Aim This work aims to evaluate a novel semi-automatic tool for the assessment of volume-strain loops by transthoracic echocardiography (TTE). The proposed method was evaluated on a typical model of left ventricular (LV) diastolic dysfunction: the cardiac amyloidosis. Method Seventeen patients with proved cardiac amyloidosis and 18 patients with heart failure with preserved ejection fraction (HFpEF) were compared to 19 controls, from a local database. All TTE were performed using Vivid E9 or E95 ultrasound system (General Electrics Healthcare, Horten, Norway). The complete method includes several steps: 1) extraction of LV strain full traces from apical 4 and 2 cavities views, 2) estimation of LV volume from these two traces by spline interpolations, 3) resampling of LV strain curves, determined for the same cardiac beat, (in apical 4-, 2- and 3- cavities views) as a function of pre-defined percentage increments of LV-volume and 4) calculation of the LV volume-strain loop area. ( Fig. 1 , panel A) Results ( Table 1 ): LVEF was similar between all groups whereas global longitudinal strain was significantly lower in amyloidosis group than controls (−14.4 vs. −20.5%; P Fig. 1 , panel B, HFpEF in green). This area was better correlated with mean e’ (r = 0.650, P Conclusion LV volume-strain loop area appears a very promising new tool to assess semi-automatically diastolic function.

Implantable accelerometers have been already proposed for the continuous monitoring of heart wall motion. Although a number of markers extracted from cardiac accelerometry have been associated with contractility, they are mainly based on uniaxial (1D) sensors, that not always reflect this relationship consistently. In this work, 3D-acceleration signals obtained from sensors located at the left ventricle (LV) of two anesthetized pigs were acquired at baseline and during dobutamine infusion, along with LV pressure. For each cardiac cycle, the reference contractility was estimated as the maximal LV pressure first derivative $(dP/dt_{max})$ . The peak of maximum energy (PE) and the peak of acceleration (PA) were computed for each accelerometry axis and for the acceleration modulus. Different polynomial curves were fitted to scatterplots representing $dP/dt_{max}$ vs. each extracted feature, in order to quantify fitting qualities. Three-dimensional features, and particularly PE, seemed to better represent contractility. Based on results, inotropism seems to be quadratically related to acceleration-based features, which may lead to more reliable LV contractility estimates when based on 3D data.

International audience