bluuebunny/crossref_metadata_2025 huggingface dataset:
Human-machine-learning integration and task allocation in citizen science
Authors: Ponti Marisa , Seredko Alena
Published: February 2022

The field of citizen science involves the participation of citizens across different stages of a scientific project; within this field there is currently a rapid expansion of the integration of humans and AI computational technologies based on machine learning and/or neural networking-based paradigms. The distribution of tasks between citizens (“the crowd”), experts, and this type of technologies has received relatively little attention. To illustrate the current state of task allocation in citizen science projects that integrate humans and computational technologies, an integrative literature review of 50 peer-reviewed papers was conducted. A framework was used for characterizing citizen science projects based on two main dimensions: (a) the nature of the task outsourced to the crowd, and (b) the skills required by the crowd to perform a task. The framework was extended to include tasks performed by experts and AI computational technologies as well. Most of the tasks citizens do in the reported projects are well-structured, involve little interdependence, and require skills prevalent among the general population. The work of experts is typically structured and at a higher-level of interdependence than that of citizens, requiring expertize in specific fields. Unsurprisingly, AI computational technologies are capable of performing mostly well-structured tasks at a high-level of interdependence. It is argued that the distribution of tasks that results from the combination of computation and citizen science may disincentivize certain volunteer groups. Assigning tasks in a meaningful way to citizen scientists alongside experts and AI computational technologies is an unavoidable design challenge.
Photon subtraction-based continuous-variable measurement-device-independent quantum key distribution with discrete modulation over a fiber-to-water channel
Authors: Yu Chao , Li Yin , Ding Jianzhi , Mao Yun , Guo Ying
Published: February 2022

We propose a discrete-modulated continuous-variable measurement-device-independent quantum key distribution protocol over a fiber-to-water channel. Different from optical fibers, the underwater channel has more severe optical attenuation because of optical absorption and scattering, which reduces the maximum communication distance. To enhance the performance of the protocol, the photon subtraction operation is implemented at the modulator side. We carry out a performance simulation in two different kinds of seawater channel, and the result shows that the scheme with photon subtraction has a longer secure communication distance under certain conditions.
Ultrafast ytterbium-doped all-fiber laser with vortex pulse emissions
Authors: Zhang Zhicheng , Wang Sha , Hu Xingwen , Wang Bangguo , Wang Jun
Published: February 2022

Ultrafast vortex pulses emitted at 1 μm band are highly sought after in many fields, here we propose an all-fiber laser for achieving that. The designed laser is switchable to emit ultrafast orbital angular momentum (OAM) and cylindrical vector beams. The beam purities are calculated to be higher than 94%. Moreover, the as-designed laser can achieve ultrafast pulse with a duration of 10.4 ps and maximum energy of 619.3 pJ. Generally, it is the shortest width and largest energy of OAM emission in ultrafast ytterbium-doped all-fiber laser so far.
High rate capability studies of triple-GEM detectors for the ME0 upgrade of the CMS muon spectrometer
Authors: Bianco M. , Fallavollita F. , Fiorina F. , Maggi M. , Pellecchia A. , Ramirez Garcia L.F. , Rosi N. , Verwilligen P.
Published: February 2022

The high-luminosity LHC (HL-LHC) upgrade is presenting new challenges for particle detector technologies. In the CMS muon system gaseous detectors, the increase in luminosity will produce a particle background ten times higher than at the LHC. To cope with the high rate environment and maintain current performance, the triple-gas electron multiplier technology is a promising candidate for high-rate capable detectors for the CMS-ME0 upgrade project in the innermost region of the forward muon spectrometer of the CMS experiment. An intense R&D and prototyping phase is currently ongoing to prove that such technology meets the stringent performance requirements of highly efficient particle detection in the harsh background environment expected in the innermost ME0 region. Here, we describe the recent rate capability studies of triple-GEM detectors operated with an Ar/CO2 (70/30) gas mixture at an effective gas gain of 2 × 104 by using a high intensity 22 keV X-ray generator. Moreover, we present a novel foil design based on double-sided segmented GEM-foils, high voltage power distribution and filtering, which the CMS muon collaboration adopted for realization of the CMS-ME0 project, and their impact on the performance of the detector in the light of new rate capability studies, with a summary of the ongoing R&D activities.
Seasonal forecasts of Eurasian summer heat wave frequency
Authors: Zhang Rui Zhi , Jia Xiao Jing , Qian Qi Feng
Published: February 2022

Heat wave events usually cause disastrous consequences on human life, economy, environment, and ecosystem. However, current climate models usually perform poorly in forecasting heat wave events. In the current work, we identified that the leading mode of the summer (June-July-August) heat wave frequency (HWF) over the Eurasian continent (HWF_EC) is a continental-scale pattern. Two machine learning (ML) models are constructed and used to perform seasonal forecast experiments for the summer HWF_EC. The potential predictive sources for the HWF_EC are chosen from the fields related to the lower boundary conditions of the atmosphere, i.e., the sea surface temperature, snow cover, soil moisture and sea ice. The specific regions and months of these lower boundary condition fields selected to construct the potential predictors are those that are persistently and significantly correlated with the variation in the HWF_EC preceding the summer. The ML forecasting models are trained with data from the period 1980–2009 and then used to perform real seasonal forecasts for the summer HWF_EC for 2010–2019. The results show that the ML forecasting models have reasonably good skills in predicting the HWF_EC over high HWF regions. The two ML models show obviously better skill in the forecasting experiments than a traditional linear regression model, suggesting that the ML models may provide an additional and useful tool for forecasting the summer HWF_EC.
Endotrivial modules for finite groups via homotopy theory
Authors: Grodal Jesper
Published: February 2022

Classifying endotrivialkGkG-modules, i.e., elements of the Picard group of the stable module category for an arbitrary finite groupGG, has been a long-running quest. By deep work of Dade, Alperin, Carlson, Thévenaz, and others, it has been reduced to understanding the subgroup consisting of modular representations that split as the trivial modulekkdirect sum a projective module when restricted to a Sylowpp-subgroup. In this paper we identify this subgroup as the first cohomology group of the orbit category on non-trivialpp-subgroups with values in the unitsk×k^\times, viewed as a constant coefficient system. We then use homotopical techniques to give a number of formulas for this group in terms of the abelianization of normalizers and centralizers inGG, in particular verifying the Carlson–Thévenaz conjecture—this reduces the calculation of this group to algorithmic calculations in local group theory rather than representation theory. We also provide strong restrictions on when such representations of dimension greater than one can occur, in terms of thepp-subgroup complex andpp-fusion systems. We immediately recover and extend a large number of computational results in the literature, and further illustrate the computational potential by calculating the group in other sample new cases, e.g., for the Monster at all primes.
Reciprocity maps with restricted ramification
Authors: Sharifi Romyar
Published: February 2022

We compare two maps that arise in study of the cohomology of global fields with ramification restricted to a finite set

S
S

of primes. One of these maps, which we call an

S
S

-reciprocity map, interpolates the values of cup products in

S
S

-ramified cohomology. In the case of

p
p

-ramified cohomology of the

p
p

th cyclotomic field for an odd prime

p
p

, we use this to exhibit an intriguing relationship between particular values of the cup product on cyclotomic

p
p

-units. We then consider higher analogues of the

S
S

-reciprocity map and relate their cokernels to the graded quotients in augmentation filtrations of Iwasawa modules.
Validation of Ideal Breast Characteristics With Breast Augmentation Patients
Authors: Kelly Jason D , Comstock Bryan , Shauly Orr , Smartt James M , Gould Daniel J
Published: February 2022

Background

Breast augmentation procedures are one of the most commonly performed aesthetic procedures in the United States. Little work has focused on the general public’s overall perception of the ideal breast or has validated them with patient photographs.

Objectives

To validate crowdsourced perceptions of breasts with their alignment to the aesthetics of breast augmentation patients.

Methods

A prospective cross-sectional study was performed using participants enrolled through the AmazonMechanical Turk crowdsourcing platform (Amazon Web Services, Amazon, Seattle, WA) to obtain participant opinions ofhow closely patient breasts aligned with previously obtained results of 4 ideal breast characteristics. Outcomes were reported based on the correlation between breast attractiveness and alignment to ideal breast characteristics, both before and after breast implant procedures.

Results

2306 responses from 737 participants reported patient photograph alignment with ideal breast projection proportion (1.0) as having the highest correlation to opinions of heightened aesthetic beauty (R = 0.98, P < 0.001), and ideal nipple direction (front) as having the lowest correlation to aesthetic beauty (R = 0.90, P < 0.001). Younger age groups (18-24) and participants with a high school diploma or less rated patients as less attractive, while married and wealthy individuals reported higher attraction levels.

Conclusions

Crowdsourcing can be a useful tool for aesthetic surgery preferences and has helped reveal key takeaways. The importance of the 4 breast characteristics has been validated, with alignment to all 4 characteristics tested having a high correlation to preferences. Differences in preference across demographic groups are a topic to further investigate.
StackTADB: a stacking-based ensemble learning model for predicting the boundaries of topologically associating domains (TADs) accurately in fruit flies
Authors: Wu Hao , Zhang Pengyu , Ai Zhaoheng , Wei Leyi , Zhang Hongming , Yang Fan , Cui Lizhen
Published: February 2022

Chromosome is composed of many distinct chromatin domains, referred to variably as topological domains or topologically associating domains (TADs). The domains are stable across different cell types and highly conserved across species, thus these chromatin domains have been considered as the basic units of chromosome folding and regarded as an important secondary structure in chromosome organization. However, the identification of TAD boundaries is still a great challenge due to the high cost and low resolution of Hi-C data or experiments. In this study, we propose a novel ensemble learning framework, termed as StackTADB, for predicting the boundaries of TADs. StackTADB integrates four base classifiers including Random Forest, Logistic Regression, K-NearestNeighbor and Support Vector Machine. From the analysis of a series of examinations on the data set in the previous study, it is concluded that StackTADB has optimal performance in six metrics, AUC, Accuracy, MCC, Precision, Recall and F1 score, and it is superior to the existing methods. In addition, the comparison of the performance of multiple features shows that Kmers-based features play an essential role in predicting TADs boundaries of fruit flies, and we also apply the SHapley Additive exPlanations (SHAP) framework to interpret the predictions of StackTADB to identify the reason why Kmers-based features are vital. The experimental results show that the subsequences matching the BEAF-32 motif play a crucial role in predicting the boundaries of TADs. The source code is freely available at https://github.com/HaoWuLab-Bioinformatics/StackTADB and the webserver of StackTADB is freely available at http://hwtad.sdu.edu.cn:8002/StackTADB.
KaruBioNet: a network and discussion group for a better collaboration and structuring of bioinformatics in Guadeloupe (French West Indies)
Authors: Couvin David , Dereeper Alexis , Meyer Damien F , Noroy Christophe , Gaete Stanie , Bhakkan Bernard , Poullet Nausicaa , Gaspard Sarra , Bezault Etienne , Marcelino Isabel , Pruneau Ludovic , Segretier Wilfried , Stattner Erick , Cazenave Damien , Garnier Maëlle , Pot Matthieu , Tressières Benoît , Deloumeaux Jacqueline , Breurec Sébastien , Ferdinand Séverine , Gonzalez-Rizzo Silvina , Reynaud Yann
Published: February 2022

Sequencing and other biological data are now more frequently available and at a lower price. Mutual tools and strategies are needed to analyze the huge amount of heterogeneous data generated by several research teams and devices. Bioinformatics represents a growing field in the scientific community globally. This multidisciplinary field provides a great amount of tools and methods that can be used to conduct scientific studies in a more strategic way. Coordinated actions and collaborations are needed to find more innovative and accurate methods for a better understanding of real-life data. A wide variety of organizations are contributing to KaruBioNet in Guadeloupe (French West Indies), a Caribbean archipelago. The purpose of this group is to foster collaboration and mutual aid among people from different disciplines using a ‘one health’ approach, for a better comprehension and surveillance of humans, plants or animals’ health and diseases. The KaruBioNet network particularly aims to help researchers in their studies related to ‘omics’ data, but also more general aspects concerning biological data analysis. This transdisciplinary network is a platform for discussion, sharing, training and support between scientists interested in bioinformatics and related fields. Starting from a little archipelago in the Caribbean, we envision to facilitate exchange between other Caribbean partners in the future, knowing that the Caribbean is a region with non-negligible biodiversity which should be preserved and protected. Joining forces with other Caribbean countries or territories would strengthen scientific collaborative impact in the region. Information related to this network can be found at: http://www.pasteur-guadeloupe.fr/karubionet.html. Furthermore, a dedicated ‘Galaxy KaruBioNet’ platform is available at: http://calamar.univ-ag.fr/c3i/galaxy_karubionet.html.

Availability and implementation Information about KaruBioNet is availabe at: http://www.pasteur-guadeloupe.fr/karubionet.html

Contact

dcouvin@pasteur-guadeloupe.fr

Supplementary information

Supplementary data are available at Bioinformatics Advances online.
GMNN2CD: identification of circRNA–disease associations based on variational inference and graph Markov neural networks
Authors: Niu Mengting , Zou Quan , Wang Chunyu
Published: February 2022

Motivation

With the analysis of the characteristic and function of circular RNAs (circRNAs), people have realized that they play a critical role in the diseases. Exploring the relationship between circRNAs and diseases is of far-reaching significance for searching the etiopathogenesis and treatment of diseases. Nevertheless, it is inefficient to learn new associations only through biotechnology.

Results

Consequently, we present a computational method, GMNN2CD, which employs a graph Markov neural network (GMNN) algorithm to predict unknown circRNA–disease associations. First, used verified associations, we calculate semantic similarity and Gaussian interactive profile kernel similarity (GIPs) of the disease and the GIPs of circRNA and then merge them to form a unified descriptor. After that, GMNN2CD uses a fusion feature variational map autoencoder to learn deep features and uses a label propagation map autoencoder to propagate tags based on known associations. Based on variational inference, GMNN alternate training enhances the ability of GMNN2CD to obtain high-efficiency high-dimensional features from low-dimensional representations. Finally, 5-fold cross-validation of five benchmark datasets shows that GMNN2CD is superior to the state-of-the-art methods. Furthermore, case studies have shown that GMNN2CD can detect potential associations.

Availability and implementation

The source code and data are available at https://github.com/nmt315320/GMNN2CD.git.
MetaMutationalSigs: comparison of mutational signature refitting results made easy
Authors: Pandey Palash , Arora Sanjeevani , Rosen Gail L
Published: February 2022

Motivation

The analysis of mutational signatures is becoming increasingly common in cancer genetics, with emerging implications in cancer evolution, classification, treatment decision and prognosis. Recently, several packages have been developed for mutational signature analysis, with each using different methodology and yielding significantly different results. Because of the non-trivial differences in tools’ refitting results, researchers may desire to survey and compare the available tools, in order to objectively evaluate the results for their specific research question, such as which mutational signatures are prevalent in different cancer types.

Results

Due to the need for effective comparison of refitting mutational signatures, we introduce a user-friendly software that can aggregate and visually present results from different refitting packages.

Availability and implementation

MetaMutationalSigs is implemented using R and python and is available for installation using Docker and available at: https://github.com/EESI/MetaMutationalSigs.
Structural connectivity associated with the sense of body ownership: a diffusion tensor imaging and disconnection study in patients with bodily awareness disorder
Authors: Errante Antonino , Rossi Sebastiano Alice , Ziccarelli Settimio , Bruno Valentina , Rozzi Stefano , Pia Lorenzo , Fogassi Leonardo , Garbarini Francesca
Published: February 2022

The brain mechanisms underlying the emergence of a normal sense of body ownership can be investigated starting from pathological conditions in which body awareness is selectively impaired. Here, we focused on pathological embodiment, a body ownership disturbance observed in brain-damaged patients who misidentify other people’s limbs as their own. We investigated whether such body ownership disturbance can be classified as a disconnection syndrome, using three different approaches based on diffusion tensor imaging: (i) reconstruction of disconnectome maps in a large sample (N = 70) of stroke patients with and without pathological embodiment; (ii) probabilistic tractography, performed on the age-matched healthy controls (N = 16), to trace cortical connections potentially interrupted in patients with pathological embodiment and spared in patients without this pathological condition; (iii) probabilistic ‘in vivo’ tractography on two patients without and one patient with pathological embodiment. The converging results revealed the arcuate fasciculus and the third branch of the superior longitudinal fasciculus as mainly involved fibre tracts in patients showing pathological embodiment, suggesting that this condition could be related to the disconnection between frontal, parietal and temporal areas. This evidence raises the possibility of a ventral self-body recognition route including regions where visual (computed in occipito-temporal areas) and sensorimotor (stored in premotor and parietal areas) body representations are integrated, giving rise to a normal sense of body ownership.
A prospective validation of a deep learning-based automated workflow for the interpretation of the echocardiogram
Authors: Tromp J , Bauer DN , Claggett BL , Frost M , Iversen MB , Prasad N , Petrie M , Larson MG , Ezekowitz JA , Solomon SD
Published: February 2022

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Us2.ai

Background. Deep learning can automate the interpretation of medical imaging tests. This study aimed to prospectively assess the interchangeability of deep learning algorithms with expert human measurements for interpreting echocardiographic studies, the primary method for assessing cardiac structure and function.

Methods. We compared a deep learning interpretation of 23 echocardiographic parameters—including cardiac volumes, ejection fraction, and Doppler measurements—with three repeated measurements by core lab human experts in a prospective study for submission to the United States Food and Drug Administration (FDA). The primary outcome metric was the individual equivalence coefficient (IEC), which compares the disagreement between deep learning and human readers relative to the disagreement among human readers. The pre-determined non-inferiority criterion was 0.25 for the upper bound of the 95% confidence interval (CI). Secondary outcomes included measures of agreement, including the mean absolute deviation.

Results. We included 602 studies from 600 participants (421 with heart failure, 179 controls, 69% women) with a mean age of 57 ± 16 years. The point estimates of IEC were all <0, indicating that the disagreement between the deep learning and human measures were lower than the disagreement among three core lab readers, and the upper bound of the 95% CI of IECs fell below the prespecified success criterion of 0.25. Secondary endpoints showed good agreement of automated with human expert measurements (Figure), with comparable or lower mean absolute deviations between automated and human experts relative to the mean absolute deviation among human experts.

Conclusion. This prospective validation study demonstrated excellent agreement between deep learning and expert human interpretation for a wide range of echocardiographic measurements. These results highlight the potential of deep learning algorithms to improve efficiency and reduce costs of echocardiography. Abstract Figure.
Three-dimensional transesophageal echocardiographic assessment of valvar and ventricular aspects in simple and complex mitral valve prolapse
Authors: Capotosto L , Tanzilli G , Iannucci G , Viceconte N , Placanica G , Mancone M , Mangieri E , Miraldi F , Vitarelli A
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Purpose. In mitral valve prolapse (MVP), preoperative assessment of repairability depends primarily on the complexity of the prolapse and is one of the most challenging roles of the echocardiologist. The aim of this study was to investigate whether three-dimensional transesophageal echocardiography helps in the evaluation of both valvar/annular and ventricular aspects in simple (single segment) and complex (multisegmental) MVP.

Methods. We studied 24 patients with mitral regurgitation due to MVP using three-dimensional transesophageal echocardiography. Mitral valve (MV), left atrium (LA) and left ventricle (LV) were analyzed. Leaflets surface area, mitral annulus antero-posterior and inter-commissural diameters, area and circumference were determined. Mitral annular disjunction (MAD) defined as a separation between LA-MV junction and LV attachment was evaluated. Papillary muscle to annulus plane distances and inter-papillary distance were obtained. LV global longitudinal and circumferential strain was assessed by speckle tracking echocardiography.

Results. Thirteen patients had complex MVP and 11 had simple MVP. Prolapse volume was 6.37 ± 4.68 mL in complex MVP and 1.59 ± 1.21 mL in simple MVP (p = 0.004). Prolapse height was 10.1 ± 2.9 mm in complex MVP and 5.8 ± 3.2 mm in simple MVP (p = 0.003). Volume/height ratio was 0.58 ± 0.29 in complex MVP and 0.21 ± 0.14 in simple MVP (p = 0.001). LV longitudinal strain had a negative correlation with change in prolapse height (r = 0.58, p < 0.001), whereas LV circumferential strain correlated with change in prolapse volume (r = 0.53, p < 0.005). Annular area was 1037 ± 191mm2 in simple MVP and 1842 ± 336mm2 in complex MVP (p < 0.01). MAD was evident in 8 complex MVP patients (61%) and 2 simple MVP patients (18%, p < 0.05). The 3D extension of MAD was significantly related to total (r = 0.54; p = 0.002) and anterior leaflet surface area (r = 0.52; p = 0.004), length from papillary muscles to coaptation (r = 0.61; p = 0.002) and regurgitant orifice (r = 0.66; p < 0.001).

Conclusions. In MVP patients 3DTEE helps to refine the characterization of simple and complex prolapse by a combined assessment of leaflets/annular details and ventricular attachment.
Right ventricular strain in in COVID-19 patients: a single-center experience
Authors: Loquias M , Valencia O , Calimbas J , Pelat J
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

BACKGROUND

Assessment of right ventricular systolic function using strain imaging analysis from two-dimensional echocardiography has been identified to have powerful predictive value. Utilization of right ventricular strain may provide additional information in the management of COVID-19 patients.

OBJECTIVE

To determine and analyze the right ventricular systolic function using longitudinal strain imaging among COVID-19 patients.

METHOD

This is a prospective cohort study of the right ventricular function using speckle tracking echocardiography among COVID-19 patients. The study included two dimensional (2D) echocardiographic studies among 137 adult patients with laboratory-confirmed COVID-19 from September to November 2020. Analysis of Variance (ANOVA) was used to compare more than two groups with numerical data. Pearson Correlation was utilized to determine correlation between numerical variables.

RESULTS

The results showed a total of 35 patients (25.54%) to have abnormal right ventricular free wall strain. The results showed that there was a significant direct correlation between right ventricular free wall strain and the echocardiographic parameters of tricuspid annular plane systolic excursion (TAPSE) (r = 0.277; p = 0.001), S’ (r = 0.166; p = 0.050), right ventricular fractional area change (r = 0.298; p < 0.0001) and left ventricular ejection fraction (LVEF) (r = 0.176; p = 0.040). There was a significant inverse correlation noted between right ventricular free wall strain and the echocardiographic parameters of the tricuspid regurgitation (r=-0.284; p = 0.001), pulmonary arterial systolic pressure (r=-0.209; p = 0.014) and left atrial size (r=-0.209; p = 0.014). There was a significant difference in the right ventricular free wall strain according to the severity of COVID-19 infection (p = 0.032). Moreover, a significant difference was also noted between right ventricular free wall strain and mortality (p = 0.0001). The mean right ventricular free wall strain of patients who died was significantly lower than those who were discharged with a mean of 18.92% and 23.59% respectively.

CONCLUSION

Right ventricular free wall strain using speckle tracking echocardiography, can be used for risk stratification for patients with COVID-19. It also showed that it is has significant correlation with the severity of the disease and mortality. These findings together with other conventional echocardiographic parameters, may provide clinicians additional information in the management of these patients.
Usefulness of myocardial work to predict long-term hard cardiovascular outcomes after ST-segment elevation acute myocardial infarction
Authors: Timoteo A , Moura Branco L , Galrinho A , Branco Mano T , Rio P , Viegas J , Cruz Ferreira R
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

 Left ventricular (LV) global longitudinal strain has demonstrated incremental prognostic value over LV ejection fraction (LVEF) in patients with ST-segment-elevation acute myocardial infarction. However, LV global longitudinal strain (GLS) does not take into consideration the effect of afterload. Myocardial work (MW) by speckle-tracking echocardiography integrates blood pressure measurements (afterload) with LV GLS and it has been recently demonstrated that Global Work Efficiency (GWE) predicts long-term all-cause mortality. It remains to be demonstrated if MW indices are associated with hard cardiovascular endpoints. The present study aimed to investigate the prognostic value of LV MW obtained from pressure-strain loops with echocardiography in patients with ST-segment-elevation myocardial infarction.

Methods

 A total of 132 consecutive patients admitted with an ST-segment-elevation acute myocardial infarction (mean age 62 ± 12 years; 76% men) that survived to discharge were retrospectively analysed. LVEF, GLS and all LVMW indices were measured by transthoracic echocardiography before discharge (4.9 ± 2.4 days after admission). All patients had at least a two-year follow-up (mean follow-up of 820 ± 155 days). Outcomes: all-cause mortality, major acute cardiovascular events (a composite of cardiovascular mortality, myocardial infarction, stroke, unplanned cardiovascular admission) and heart failure hospitalization.

Results

 In the two-year follow-up, 6 patients died, there were 18 patients with MACE, and 3 patients were hospitalized with heart failure. We confirmed that for all-cause mortality, GWE and GWI showed better discrimination compared to GLS (Table), with a cut-off of 83% and 1066 mmHg% (log-rank < 0,001) respectively. However, ROC curve comparisons were not significantly different. For MACE, the performance of all methods is suboptimal, with an AUC < 0.65 for all variables, except for GLS. For heart failure admission, performance is slightly better, but GLS is still the best parameter to predict this event.

Conclusions

 LVGWE and GWI are better predictors of all-cause mortality compared to GLS, but MW indices failed to demonstrate a prognostic impact in long-term cardiovascular events. Prospective studies are warranted to confirm this finding. Abstract Figure.
Early systolic lengthening in patients with ST-elevation myocardial infarction: a novel tool for risk stratification
Authors: Ferreira C , Freitas A , Martinho S , Goncalves V , Almeida J , Campos G , Rosa J , Guimaraes J , Baptista R , Castro G , Goncalves L
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

After an ST-elevation myocardial infarction (STEMI), the risk of subsequent cardiovascular events is high. Risk stratification at index hospitalization remains a core challenge, especially in patients with subtle changes in LV function. Early systolic lengthening (ESL) may occur in ischemic myocardial segments with reduced contractile force and it has been correlated with infarct size and prognosis in STEMI patients with mildly impaired LV function. In this study, we aimed to evaluate the correlation of ESL with common echocardiographic parameters and its prognostic value in STEMI patients with preserved LV function.

Methods

We retrospectively included all the patients admitted to an intensive care unit with STEMI and a left ventricle ejection fraction ≥55% from January to June of 2016. Patients with inadequate image quality for speckle tracking echocardiographic examination were excluded (n = 14). We evaluated the ESL index, defined as follows: [−100×(peak positive systolic strain/peak negative strain in cardiac cycle)], and ESL duration.

Results

A total of 37 patients were included in the study. Mean age was 63 ± 12 years with a male preponderance (81%). All patients were submitted to complete revascularization. Median values of the ESL index and ESL duration were 7% (IQR, 4%–10%) and 37 msec (IQR, 21–55 msec), respectively. No significant differences were found between ESL index and ESL duration groups, except for a higher prevalence of heart failure at hospitalization in both highest groups, and women were more prevalent in the ESL index higher group (Tables 1 and 2). ESL index was correlated with post-systolic index (PSI) (r2 = 0.34, p = 0.04) and showed a weak correlation with E/A ratio (r2=-0.37, p = 0.02). ESL duration was correlated with ESL index (r2 = 0.76, p < 0.001) and PSI (r2 = 0.43, p = 0.008). During a median follow-up of 3.2 years (interquartile range, 2.9–3.4 years), 7 (18.9%) patients experienced major adverse cardiovascular events (MACE), a composite of heart failure admission, myocardial infarction, and all-cause mortality Both ESL index (HR 2.5; 95%CI 1.2–5.3; P = 0.02) and ESL duration (HR 1.7; 95%CI 1.1–2.7; P = 0.02) were independent predictors of MACE. Both associations remained significant after adjusting for clinical confounders.

Conclusions

In our cohort of STEMI patients with preserved LV function, assessment of ESL yielded important and significant prognostic information on MACE. ESL may be a useful tool to enhance routine risk stratification in this population. Abstract TABLE 1  Abstract TABLE 2
Left atrial functional reverse remodeling assessed by speckle tracking echocardiography in a real-life population of patients with chronic heart failure after therapy with sacubitril/valsartan
Authors: Magnesa M , Correale M , Correale M , Correale M , Mazzeo P , Mazzeo P , Mazzeo P , Fortunato M , Fortunato M , Fortunato M , Leopizzi A , Leopizzi A , Leopizzi A , Mallardi A , Mallardi A , Mallardi A , Tricarico L , Tricarico L , Tricarico L , Mennella R , Mennella R , Mennella R , Iacoviello M , Iacoviello M , Iacoviello M , Brunetti ND , Brunetti ND , Brunetti ND
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

Left atrial (LA) enlargement has been demonstrated to be a predictor of adverse cardiovascular outcomes, such as atrial fibrillation (AF), heart failure (HF), and cardiovascular death (1). Previous studies showed left atrial structural reverse remodeling (LARR), defined as >15% reduction in LA end-systolic volume index (LAESVi) (2), can be achieved after therapy with Sacubitril/Valsartan (S/V) in real-world settings. On the other hand, LA functional reverse remodeling is not well defined.

Purpose

We sought to investigate the association between left atrial (LA) structural and functional remodelling in patients with chronic heart failure after therapy with S/V.

Methods

Patients with chronic HF, LV dysfunction (EF < 35%), NYHA class II-III were followed up between September 2019 and March 2020. All patients underwent clinical and echocardiography follow up at baseline and after 6 months of therapy with S/V. Measures of LA structure [LA end-systolic volume index (LAESVi)] and function [left atrial ejection fraction (LAEF), peak atrial longitudinal strain (PALS), LA conduit strain, and peak atrial contraction strain (PACS)] were calculated. We divided our population into two subgroups based on whether reverse remodeling was achieved (LARR+) or not (LARR-).

Results

Forty-seven consecutive outpatients (mean age 66 ± 8 years; 85% males) were enrolled in the study. At follow-up visit, a positive LARR was found in nearly half of patients treated with S/V, resulting in line with previous studies (3). Furthermore, global PALS was significantly improved in both groups compared to baseline (15 ± 7 vs 19 ± 8 %, p < 0.001), but the LARR+ group showed an improvement that was twice higher (55 ± 66 vs 25 ± 26, p = 0.039), supporting the potential role of PALS as marker of functional LARR.

Conclusions

Treatment with S/V in patients with systolic dysfunction is associated with an improvement in LA structural and functional remodelling in a real-world scenario. Therefore, PALS could be the benchmark for the assessment of left atrial functional reverse remodeling.
Left atrial function after standalone totally thoracoscopic left atrial appendage exclusion in af patients with absolute contraindication to oral anticoagulation therapy
Authors: Tedoldi F , Branzoli S , D"onghia G , Fanti D , Sarao E , Guarracini F , Quintarelli S , Graffigna A , Bonmassari R , La Meir M , Monaco C , De Asmundis C , Marini M
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Introduction

Left atrial appendage (LAA) is the source of more than 90% of thrombi in patients with atrial fibrillation (AF).  The Totally Thoracoscopic (TT) LAA exclusion with epicardial clip has become a safe and effective procedure, but the effect on left atrial (LA) function remains unknown.

Purpose

The aim of this study was to assess the effect of TT LAA exclusion on LA function.

Methods

20 patients (15 males) with non-valvular AF and contraindication to oral anticoagulation therapy (OAT) or antiplatelet therapy underwent standalone TT LAA exclusion with the Atriclip Pro II device. All patients were screened preoperatively with 3D CT scan, trans-esophageal echocardiography, spirometry and cerebrovascular doppler ultrasound. Intraoperative Atriclip Pro II positioning and LAA exclusion were guided and confirmed by trans-esophageal echo. To objectify LA function, transthoracic echocardiography with 2D Speckle tracking was performed before surgery, at discharge and at 3-month follow-up. All patients were not on anticoagulation nor antiplatelet therapy at the time of surgery, at discharge and at control visit.

Results

Baseline characteristics are reported in Table I. There were no major complications during the procedures. One non cardiovascular death, one minor stroke and 4 hospitalizations occur at 1-year follow up. The reservoir LA function considering the strain measurements dramatically decreased few days after the procedure and it recovered at 3-month follow-up compared to baseline, even though the LA volume is augmented (Table II). Furthermore, NT pro-BNP increased and ventricular strain decreased significantly after the procedure recovering over time.

Conclusion

TT LAA exclusion with Atriclip Pro II device is a safe and effective procedure in preventing AF related stroke in patients with contraindication to OAT. Our findings suggest that the LAA epicardial clip impairs immediately the reservoir LA function that recovers over time. Abstract Table I  Abstract Table II
Three-dimensional principal strain, twist and torsion as predictors of cancer therapeutics related cardiac dysfunction in breast cancer patients
Authors: Park CS
Published: February 2022

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Research Foundation of Korea

Background

Breast cancer patients usually received anti-cancer chemotherapy even in the early stage. Main regimen includes anthracycline and trastuzumab which are known to have cardiotoxicity. Three-dimensional echocardiography can provide all conventional and deformational parameters in one image but its utility is limited.

Methods

The patients underwent adriamycin based chemotherapy and three-dimensional echocardiography before and 1 year after were included. All the analyses of 3-dimensioanl echocardiographic images were performed using 4D LV Analysis (TomTec, Unterschleissheim, Germany). Cancer therapeutics related cardiac dysfunction was defined as decrease in the value of longitudial strian more than 15 % in the follow up compared to the pre-chemotherapy exam.

Results

: The number of patients was 75. One patient was admitted due to symptoms related to heart failure. Multivariate logistic regression analysis showed that 3-dimensional longitudial strian measured before chemotherapy can predict CTRCD (Odds ratio; 95% confidence interval: 0.63; 0.42-0.93. p value = 0.02).

Conclusion

3-dimensional deformation parameters can be used as predictors of CTRCD in breast cancer patients and it should be applied more widely in clinical settings. Abstract Figure. Usefulness as a predictor
Myocardial work indices in living kidney donor population
Authors: Akdeniz C , Yurdakul S , Cetinarslan O , Canbolat IP , Ucar Z , Sinangil A , Barlas S , Akin B
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

Living kidney donors represent a very special group of patients who are screened for cardiovascular morbidity preoperatively  and remained with mildly reduced renal function after unilateral nephrectomy. The effect of  unilateral nephrectomy on cardiovascular disease progression or subclinical cardiac dysfunction is still controversial. Myocardial deformation imaging allows left ventricular function quantification beyond ejection fraction. Non invasive assessment of myocardial work (MW) is a novel, promising speckle tracking- based method  which  can provide us to detect subtle myocardial dysfunction with advantages of  load independency.

We aimed to assess the impact of mildly reduced renal function after kidney donation, on subclinical cardiac structural and functional status.

Methods

We included seventeen kidney donors and seventeen  age and sex matched healthy controls. All participants underwent transthoracic echocardiography (TTE). In addition to standard TTE measurements, 2D speckle – tracking  based strain analysis was performed for left ventricle (LV) and right ventricle (RV). We also calculated Global Work Index (GWI) as the area of LV pressure-strain loop as a product of strain and x systolic blood pressure. MW efficieny (MWE), Global Constructive Work (GCW) and Global Wasted Work (GWW)  were also calculated.

Results

There was no difference between the patients and the control group, regarding conventional parameters such as LV ejection fraction, Tricuspidal annular systolic excursion (TAPSE) and systolic pulmonary artery pressure. Left  ventricular global longitudinal strain (GLS) and right ventricular global longitudinal strain were both significantly reduced in patient group (LV GLS ; -17,4% ,-19% p = 0,002 , RV GLS -19%, -24% p= 0,002 ). We found GWI and GCW were  significantly lower in patients (mean 1549 mmHg% to 1800 mmHg%, p = 0,008) (mean 1857 mmHg% to 2176 mmHg%, p = 0,008),  while GWW and MWE did not differ between the groups. We could not detect any significant correlation between MW indices and glomeruler filtration rate(GFR), time after surgery or hypertension.

Conclusion

Kidney donation may be associated with increased risk of subclinical cardiac dysfunctions. Myocardial Work might be a valuable diagnostic tool to detect subtle cardiac changes in this unique population.
Diagnostic value of parameters of myocardial work in patients after myocardial infarction with ST segment elevation
Authors: Oleinikov V , Babina A , Golubeva A , Galimskaya V
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Objective

to reveal the differences in the global parameters of myocardial work of the left ventricle (LV) in patients with preserved LV ejection fraction (EF) after ST-segment elevation myocardial infarction (STEMI) and healthy individuals.

Methods

the study included 45 people with primary STEMI (group 1): 13 women and 32 men aged 38 to 66 years (52.3 ± 7.4). The control group (group 2) consisted of 70 healthy individuals aged 39.3 ± 8.9 years, including 34 men and 36 women. Myocardial infarction was confirmed by ECG data, a diagnostically significant level of cardiospecific markers (troponin T, CPK-MB) and by the results of coronary angiography with the presence of one infarct-related coronary artery in the absence of hemodynamically significant stenosis of other arteries. Echocardiography was performed on the 7th-9th day and 6 months after STEMI using a Vivid GE 95 Healthcare ultrasound scanner (USA). Echocardiographic image analysis was performed using EchoPAC software version 202 (GE Healthcare). The standard echo parameters were determined: end-diastolic volume (EDV, ml), end-systolic volume (ESV, ml), LV myocardial mass index (LVMI, g / m2), EF by the Simpson biplane method,%. The preserved EF was considered the value of EF greater than or equal to 50%. The following indicators of myocardial work were assessed: global myocardial work index (GWI, mm Hg%), global constructive work (GCW, mm Hg%), global wasted work (GWW, mm Hg%), global work efficiency (GWE,%). Statistical data processing was performed using the Statistica 13.0 software package (StatSoft Inc., USA).

Results

6 months after STEMI, 26 subjects had an EF ≥50% (58.8 ± 5.8%). The mean LVEF in group 2 was 60.8 ± 4.6% (p = 0.12). EDV in group 1 was 122.5 [95% CI 104.4; 140.7] ml, in group 2 - 104.7 [95% CI 99.1; 110.3] ml (p = 0.003). ESV in group 1 - 83.8 [95% CI 28.5; 139.0] ml, in group 2 - 40.7 [95% CI 37.6; 43.7] ml (p = 0.02); in group 1, LVMI was 89.3 [95% CI 77.4; 101.1] g / m2, in group 2 - 67.4 [95% CI 63.7; 71.1] g / m2 (p = 0.03). GWI was 1890.1 [95% CI 1730.0; 2050.2] mm Hg% in group 1, in group 2 - 2039.8 [95% CI 1956.3; 2123.3] mmHg% (p = 0.002), GCW - 2132.4 [95% CI 1958.5; 2306.3] mmHg% and 2335.5 [95% CI 2251.7; 2419.4] mm Hg% (p = 0.003), respectively. GWE 95.4 [95% CI 94.1; 96.6] and 97.1 [95% CI 96.8; 97.4]% (p = 0.02), GWW 76.6 [95% CI 55.9; 97.3] and 50.0 [95% CI 44.0; 56.0] m Hg% (p = 0.06) in the corresponding groups.

Conclusion

Thus, despite the satisfactory values of LVEF, the indicators of myocardial work, except for global wasted work, had lower values in patients with STEMI compared with healthy individuals.
Impaired myocardial work in paediatric patients with wolff-parkinson-white syndrome
Authors: Borrelli N , Di Salvo G , Ciriello GD , Sabatino J , Bucciarelli V , Grimaldi N , Barracano R , Fusco F , Merola A , Correra A , Romeo E , Palma M , Scognamiglio G , Russo MG , Sarubbi B
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

Wolff-Parkinson-White Syndrome (WPW) has been associated with reduced local myocardium deformation during systole. Left ventricle (LV) dysfunction due to electrical dyssynchrony may require catheter ablation of the accessory pathway, even in asymptomatic patients.

Purpose

The study aimed to assess the diagnostic value of non-invasive myocardial work in predicting subtle myocardial abnormalities in patients with WPW.

Methods

Forty-four paediatric patients (age 8.2 ± 4.3 years) were included in the study: 12 cases with manifest WPW and 32 age-, sex- and arterial pressure- matched controls (CTR). LV ejection fraction (EF) and global longitudinal strain (GLS) were evaluated. Global myocardial work index (MWI) was measured as the area of the LV pressure-strain loops. From MWI, global Constructive Work (MCW), Wasted Work (MWW) and Work Efficiency (MWE) were estimated.

Results

Despite normal LV systolic function by standard echocardiographic parameters, patients with WPW had lower MWI (1233.5 ± 281.6 mmHg% in WPW vs 1624.0 ± 305.8 mmHg% in CTR, p = 0.0004), MCW (1833.4 ± 257.9 mmHg% in WPW vs 2069.0 ± 319.9 mmHg% in CTR, p= 0.03), MWW (187.6 ± 117.7 mmHg% in WPW vs 90.9 ± 58.9 mmHg% in CTR, p= 0.0008) and GWE (90.5 ± 4.8% in WPW vs 95.2 ± 2.2% in CTR, p= 0.00006). There were no significant differences in GLS and EF between patients with WPW and controls.

Conclusion

Myocardial work indices were found significantly reduced in patients with WPW, even in presence of normal LV EF and GLS. In patients with WPW, MWI may represent a sensitive measure of myocardial dysfunction and help in the decision-making for catheter ablation. Abstract Figure. Myocardial work in WPW  Abstract Figure. Myocardial work in control patient