bluuebunny/crossref_metadata_2025 huggingface dataset:
Welding of 304 stainless steel and glass using high-repetition-frequency femtosecond laser
Authors: Wang Yipeng , Li Yang , Ao Sansan , Luo Zhen , Zhang Di
Published: October 2021

In this study, a femtosecond laser with a repetition frequency of 0–400 kHz was used to join soda lime glass and 304 stainless steel. The effects of single-pulse power, repetition frequency, welding speed, and defocusing on the weld quality were investigated. The joining mechanism and fracture surface morphologies were studied using scanning electron microscopy and x-ray diffraction analysis. The results show that no new phases were formed between the glass and stainless steel, and that the joining mechanism consisted mainly of mechanical mixing between the two materials. Using a suitable combination of process parameters, a good weld with a strength of 8.79 MPa was obtained. The weld strength was influenced mainly by the amount of glass that adhered to the stainless steel, the bonding strength between the glass base material and the remelted glass, and the wetting of the stainless steel by the molten glass.
Challenges and opportunities to regulate mineral transport in rice
Authors: Bashir Khurram , Ishimaru Yasuhiro
Published: October 2021

Iron (Fe) is an essential mineral for plants, and its deficiency as well as toxicity severely affects plant growth and development. Although Fe is ubiquitous in mineral soils, its acquisition by plants is difficult to regulate particularly in acidic and alkaline soils. Under alkaline conditions, where lime is abundant, Fe and other mineral elements are sparingly soluble. In contrast, under low pH conditions, especially in paddy fields, Fe toxicity could occur. Fe uptake is complicated and could be integrated with copper (Cu), manganese (Mn), zinc (Zn), and cadmium (Cd) uptake. Plants have developed sophisticated mechanisms to regulate the Fe uptake from soil and its transport to root and above-ground parts. Here, we review recent developments in understanding metal transport and discuss strategies to effectively regulate metal transport in plants with a particular focus on rice.
Female preference for color-enhanced males: a test of the sensory bias model in medaka, a drab fish
Authors: Downer-Bartholomew Benjamin M B , Rodd F Helen
Published: October 2021

Sexual selection research has long focused on the evolution of female mate preferences. Most of the models that have been developed posit that mate preferences evolve in a mating context. In contrast, the sensory bias model proposes that mate choice preferences arise in a non-mating context, as a by-product of natural selection acting on a female’s perceptual system. Recent research has shown that many species of fishes, from across a large clade including poeciliids, goodeids, and medaka, have a bias for long wavelength (LW) colors (yellow, orange, red) in a non-mating context. Even species that do not have LW-colored ornaments, apparently because they have been lost secondarily, retain this latent bias for LW colors. Here, we predicted that female Oryzias latipes (Japanese medaka), a drab species with a latent preference for LW colors, would show a mate choice preference for males with an artificial secondary sexual trait—a colored stripe added to their flank. We confirmed that females were more responsive to red and orange objects in a non-mating context than to other colors. We also showed that females were less resistant towards males with an LW-colored stripe than to those enhanced with a non-LW stripe and that, for many females, responses towards specific LW colors were consistent across these non-mating and mating contexts. Therefore, our results provide support for the sensory bias model by providing a link between a sensory bias in a non-mating context and a mate choice preference in a drab species like medaka.
Comparative studies on the high-performance compression of SARS-CoV-2 genome collections
Authors: Tang Tao , Li Jinyan
Published: October 2021

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is fast mutating worldwide. The mutated strains have been timely sequenced by worldwide labs, accumulating a huge amount of viral genome sequences open to public for biomedicine research such as mRNA vaccine design and drug recommendation. It is inefficient to transmit the millions of genome sequences without compression. In this study, we benchmark the performance of reference-free and reference-based compression algorithms on SARS-CoV-2 genome collections extracted from NCBI. Experimental results show that reference-based two-level compression is the most suitable approach to the compression, achieving the best compression ratio 1019.33-fold for compressing 132 372 genomes and 949.73-fold for compressing 416 238 genomes. This enormous file size reduction and efficient decompression have enabled a 5-min download and decompression of $10^5$ SARS-CoV-2 genomes. As compression on datasets containing such big numbers of genomes has been explored seldom before, our comparative analysis of the state-of-the-art compression algorithms provides practical guidance for the selection of compression tools and their parameters such as reference genomes to compress viral genome databases with similar characteristics. We also suggested a genome clustering approach using multiple references for a better compression. It is anticipated that the increased availability of SARS-CoV-2 genome datasets will make biomedicine research more productive.
PMLB v1.0: an open-source dataset collection for benchmarking machine learning methods
Authors: Romano Joseph D , Le Trang T , La Cava William , Gregg John T , Goldberg Daniel J , Chakraborty Praneel , Ray Natasha L , Himmelstein Daniel , Fu Weixuan , Moore Jason H
Published: October 2021

Motivation

Novel machine learning and statistical modeling studies rely on standardized comparisons to existing methods using well-studied benchmark datasets. Few tools exist that provide rapid access to many of these datasets through a standardized, user-friendly interface that integrates well with popular data science workflows.

Results

This release of PMLB (Penn Machine Learning Benchmarks) provides the largest collection of diverse, public benchmark datasets for evaluating new machine learning and data science methods aggregated in one location. v1.0 introduces a number of critical improvements developed following discussions with the open-source community.

Availability and implementation

PMLB is available at https://github.com/EpistasisLab/pmlb. Python and R interfaces for PMLB can be installed through the Python Package Index and Comprehensive R Archive Network, respectively.
GPSmatch: an R package for comparing Genomic-binding Profile Similarity among transcriptional regulators using customizable databases
Authors: Dong Amy , Bao Xiaomin
Published: October 2021

Eukaryotic gene expression requires coordination among hundreds of transcriptional regulators. To characterize a specific transcriptional regulator, identifying how it shares genomic-binding sites with other regulators can generate important insights into its action. As genomic data such as chromatin immunoprecipitation assays with sequencing (ChIP-Seq) are being continously generated from individual labs, there is a demand for timely integration and analysis of these new data. We have developed an R package, GPSmatch (Genomic-binding Profile Similarity match), for calculating the Jaccard index to compare the ChIP-Seq peaks from one experiment to other experiments stored in a user-supplied customizable database. GPSmatch also evaluates the statistical significance of the calculated Jaccard index using a nonparametric Monte Carlo procedure. We show that GPSmatch is suitable for identifying and ranking transcriptional regulators with shared genomic-binding profiles, which may unravel potential mechanistic actions of gene regulation.

Availability and implementation

The software is freely available at https://github.com/Bao-Lab/GPSmatch.

Supplementary information

Supplementary data are available at Bioinformatics online.
Plasma sTREM2: a potential marker of cerebrovascular injury in neurodegenerative disorders
Authors: Rodriguez-Vieitez Elena , Ashton Nicholas J
Published: October 2021

This scientific commentary refers to ‘Plasma soluble TREM2 is associated with white matter lesions independent of amyloid and tau’ by Tsai et al. (doi:10.1093/brain/awab332).
MCT1 expression is independently related to shorter cancer-specific survival in clear cell renal cell carcinoma
Authors: de Carvalho Paulo Afonso , Bonatelli Murilo , Cordeiro Maurício Dener , Coelho Rafael Ferreira , Reis Sabrina , Srougi Miguel , Nahas Willian Carlos , Pinheiro Celine , Leite Katia Ramos Moreira
Published: October 2021

Clear cell renal cell carcinoma (ccRCC) has been considered a metabolic disease, with loss of von Hippel-Lindau (VHL) gene and consequent overexpression of hypoxia-inducible factor 1 alpha (HIF-1α), which is central for tumor development and progression. Among other effects, HIF-1α is involved in the metabolic reprogramming of cancer cells towards the Warburg effect involved in tumor cell proliferation, migration and survival. In this context, several proteins are expressed by cancer cells, including glucose and lactate transporters as well as different pH regulators. Among them, monocarboxylate transporters (MCTs) can be highlighted. Our aim is to comprehensively analyze the immunoexpression of MCT1, MCT2, MCT4, CD147, CD44, HIF-1α, GLUT1 and CAIX in ccRCC surgical specimens correlating with classical prognostic factors and survival of patients with long follow-up. Surgical specimens from 207 patients with ccRCC who underwent radical or partial nephrectomy were used to build a tissue microarray. Immunostaining was categorized into absent/weak or moderate/strong and related to all classic ccRCC prognostic parameters. Kaplan–Meier curves were generated to assess overall and cancer-specific survival, and multivariate analysis was performed to identify independent prognostic factors of survival. Multivariate analysis showed that MCT1 together with tumor size and TNM staging, were independently related to cancer-specific survival. MCT1, CD147, CD44 and GLUT1 expression were significantly associated with poor prognostic factors. We show that MCT1 is an independent prognostic factor for cancer-specific survival in ccRCC justifying the use of new target therapies already being tested in clinical trials.
Impact of contrast-induced acute kidney injury on long-term major adverse cardiovascular events and kidney function after percutaneous coronary intervention: insights from a territory-wide cohort study in Hong Kong
Authors: Ng Andrew Kei-Yan , Ng Pauline Yeung , Ip April , Lam Lap-tin , Ling Ian Wood-Hay , Wong Alan Shing-Lung , Yap Desmond Yat-Hin , Siu Chung-Wah
Published: October 2021

Background

The impact of contrast-induced acute kidney injury (CI-AKI) on long-term major adverse cardiovascular events (MACE) remains controversial.

Method

This was a retrospective cohort study from 14 hospitals under the Hospital Authority of Hong Kong between 2004 and 2017. Severe CI-AKI was defined as an increase in serum creatinine of >50% from the baseline value, an absolute increase of >1 mg/dL (88 μmol/L) or requiring dialysis after percutaneous coronary intervention (PCI). Mild CI-AKI was defined as an increase in serum creatinine of >25% from the baseline value or an absolute increase of >0.5 mg/dL (44 μmol/L) after PCI but not fulfilling the criteria for severe CI-AKI. The primary endpoint was MACE, defined as a composite outcome of all-cause mortality, non-fatal myocardial infarction after hospital discharge, stroke or any unplanned coronary revascularization, in a time-to-first-event analysis up to 5 years after PCI. The secondary endpoints were individual components of MACE and cardiovascular mortality.

Results

A total of 34 576 patients were analysed. After adjustment for cardiovascular risk factors, procedural characteristics and medication use, the risk of MACE at 5 years was significantly higher with mild CI-AKI {hazard ratio [HR], 1.18 [95% confidence interval (CI) 1.12–1.26); P < 0.001} and severe CI-AKI [HR 1.92 (95% CI 1.78–2.07); P < 0.001]. Severe CI-AKI was associated with higher adjusted risks of each secondary end point and the risks monotonically accrued over time.

Conclusions

Among patients undergoing a first-ever PCI, CI-AKI of any severity was associated with a higher adjusted risk of MACE at 5 years. Severe CI-AKI has a stronger association with MACE and its individual components, with an excess of early and late events.
Applications of Digital Microscopy and Densely Connected Convolutional Neural Networks for Automated Quantification of Babesia-Infected Erythrocytes
Authors: Durant Thomas J S , Dudgeon Sarah N , McPadden Jacob , Simpson Anisia , Price Nathan , Schulz Wade L , Torres Richard , Olson Eben M
Published: October 2021

Background

Clinical babesiosis is diagnosed, and parasite burden is determined, by microscopic inspection of a thick or thin Giemsa-stained peripheral blood smear. However, quantitative analysis by manual microscopy is subject to error. As such, methods for the automated measurement of percent parasitemia in digital microscopic images of peripheral blood smears could improve clinical accuracy, relative to the predicate method.

Methods

Individual erythrocyte images were manually labeled as “parasite” or “normal” and were used to train a model for binary image classification. The best model was then used to calculate percent parasitemia from a clinical validation dataset, and values were compared to a clinical reference value. Lastly, model interpretability was examined using an integrated gradient to identify pixels most likely to influence classification decisions.

Results

The precision and recall of the model during development testing were 0.92 and 1.00, respectively. In clinical validation, the model returned increasing positive signal with increasing mean reference value. However, there were 2 highly erroneous false positive values returned by the model. Further, the model incorrectly assessed 3 cases well above the clinical threshold of 10%. The integrated gradient suggested potential sources of false positives including rouleaux formations, cell boundaries, and precipitate as deterministic factors in negative erythrocyte images.

Conclusions

While the model demonstrated highly accurate single cell classification and correctly assessed most slides, several false positives were highly incorrect. This project highlights the need for integrated testing of machine learning-based models, even when models in the development phase perform well.
Community detection in social networks by incorporating the preferential selection
Authors: Meena Shyam Sundar , Tokekar Dr. Vrinda
Published: October 2021

In the last decade, online social networks (OSNs) have become popular among researchers. Now, almost a third of the world’s population uses it. The recent boom of technologies provides opportunities to improve the processing and mining of social data. The proposed approach detects communities in the OSNs using the concepts of a preferential selection of neighbours. The proposed work is evaluated on real-world datasets as well as computer-generated datasets. It is also compared with other state-of-the-art community detection algorithms for normalized mutual information and F1-measure values. The cumulative performance of the algorithm is found to be superior, which outperforms other state-of-the-art community detection algorithms.
Spectral density of random graphs: convergence properties and application in model fitting
Authors: Santos Suzana de Siqueira , Fujita André , Matias Catherine
Published: October 2021

Random graph models are used to describe the complex structure of real-world networks in diverse fields of knowledge. Studying their behaviour and fitting properties are still critical challenges that, in general, require model-specific techniques. An important line of research is to develop generic methods able to fit and select the best model among a collection. Approaches based on spectral density (i.e. distribution of the graph adjacency matrix eigenvalues) appeal to that purpose: they apply to different random graph models. Also, they can benefit from the theoretical background of random matrix theory. This work investigates the convergence properties of model fitting procedures based on the graph spectral density and the corresponding cumulative distribution function. We also review the convergence of the spectral density for the most widely used random graph models. Moreover, we explore through simulations the limits of these graph spectral density convergence results, particularly in the case of the block model, where only partial results have been established. random graphs, spectral density, model fitting, model selection, convergence.
Artificial intelligence in cardiology: the debate continues
Authors: Asselbergs Folkert W , Fraser Alan G
Published: October 2021

In 1955, when John McCarthy and his colleagues proposed their first study of artificial intelligence, they suggested that ‘every aspect of learning or any other feature of intelligence can in principle be so precisely described that a machine can be made to simulate it’. Whether that might ever be possible would depend on how we define intelligence, but what is indisputable is that new methods are needed to analyse and interpret the copious information provided by digital medical images, genomic databases, and biobanks. Technological advances have enabled applications of artificial intelligence (AI) including machine learning (ML) to be implemented into clinical practice, and their related scientific literature is exploding. Advocates argue enthusiastically that AI will transform many aspects of clinical cardiovascular medicine, while sceptics stress the importance of caution and the need for more evidence. This report summarizes the main opposing arguments that were presented in a debate at the 2021 Congress of the European Society of Cardiology. Artificial intelligence is an advanced analytical technique that should be considered when conventional statistical methods are insufficient, but testing a hypothesis or solving a clinical problem—not finding another application for AI—remains the most important objective. Artificial intelligence and ML methods should be transparent and interpretable, if they are to be approved by regulators and trusted to provide support for clinical decisions. Physicians need to understand AI methods and collaborate with engineers. Few applications have yet been shown to have a positive impact on clinical outcomes, so investment in research is essential.
Diagnostic and prognostic contribution of 99mTc-DPD scintigraphy in transthyretin V30M cardiac amyloidosis
Authors: Azevedo Coutinho M D C , Cortez-Dias N , Cantinho G , Goncalves S , Cunha N , Rodrigues T , Santos L , Conceicao I , Pinto F
Published: October 2021

Background

Early diagnosis and prognostic stratification of hereditary transthyretin amyloidosis (ATTR) are crucial. Previous findings suggested that 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scintigraphy presents suboptimal accuracy to detect ATTR cardiomyopathy caused by V30M mutation, particularly in patients with onset of symptoms under 50 years of age. Furthermore, its prognostic value has never been evaluated in ATTR caused by this mutation.

Purpose

To assess the diagnostic value of DPD scintigraphy to detect cardiomyopathy in a large cohort of patients with ATTR-V30M mutation and to explore its prognostic value regarding mortality.

Methods

Of the 305 ATTR-V30M mutation carriers followed prospectively and who underwent DPD scintigraphy, 288 individuals [median age 46 (39–56); 49% male] without myocardial thickening attributable to other causes were enrolled in the study. Amyloid cardiomyopathy was defined by septal thickness ≥13mm not attributable to other causes plus at least one of the following criteria: (1) late heart-to-mediastinum (H/M) 123I-metaiodobenzylguanidine (MIBG) ratio <1.60; (2) electrical heart disease (arrhythmia or cardiac conduction defect); or (3) amyloid infiltration documented in biopsy.

Results

Amyloid cardiomyopathy was identified in 41 (14.2%) patients and 44 (15.3%) individuals presented abnormal cardiac DPD uptake. Individuals with cardiac DPD retention had 27-fold higher likelihood of having amyloid cardiomyopathy (OR: 27.4; 95% CI 11.6–65.0; P<0.001). However, DPD scintigraphy presented suboptimal accuracy to detect ATTR cardiomyopathy (89.9%) with limitations in sensitivity (56.1%), specificity (95.6%), positive predictive value (67.7%) and negative predictive value (92.9%).

During a mean follow-up 33.6±1.2 months, 16 patients died (5.6%). Mortality was 14 times higher in patients with amyloid cardiomyopathy (HR: 14.1; 95% CI 4.9–40.7; P<0.001), 13 times higher in those with abnormal cardiac DPD uptake (HR: 12.59; 95% CI % 4.56–34.72; P<0.001) and 10 times higher in those with H/M MIBG ratio <1.60 (HR: 10.40; 95% CI 2.95–36.69; P<0.001). The prognostic value of ventricular thickness and cardiac DPD uptake was additive: patients without septal thickening and no cardiac DPD retention had excellent prognosis (5-year mortality of 0.75%), while those with septal thickening and/or abnormal DPD retention presented 5-year mortality rates ranging from 39.9 to 53.3%.

Conclusions

DPD scintigraphy is valuable in the evaluation of ATTR-V30M mutation carriers, particularly for prognostic stratification purposes, identifying patients at higher risk of death.

Funding Acknowledgement

Type of funding sources: None.
Epicardial adipose tissue and nonvalvular atrial fibrillation
Authors: Arakelyan M , Golukhova E Z , Gromova O I , Bulaeva N I
Published: October 2021

Background

Several studies revealed the relationship between epicardial fat tissue (EF) and development of atrial fibrillation (AF). Though pathophysiological mechanisms are not clear enough, the anatomy and location EF as a part of visceral adiposity tissue could lead to proinflammatory and fibrotic changes in atrial myocardium.

Purpose

To evaluate the paracrine effects of EF and detect the association of tissue Doppler imaging (TDI) parameters, EF thickness by cardiac magnetic resonance tomography (CMR) and biochemical markers of fibrosis and inflammation in patients with nonvalvular AF without concomitant coronary artery disease.

Methods

Thirty-nine patients with idiopathic paroxysmal AF, normal or slightly enlarged left atria (LA) (mean LA diameter 4,5±0,6cm) were included. The mean age was 50,8±13,9 y.o., 19 (49%) were men. The absence of coronary lesions was confirmed by angiography in all cases. Besides standard ECG and ECHO, all patients underwent TDI and CMR with late gadolinium enhancement. EP thickness at anterior left ventricular (LV) wall was estimated by CMR. The myocardial fibrotic and proinflammatory biomarkers levels - matrix metalloproteinases (MMP-2, MMP-9), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) were estimated. Kendall rank correlation coefficient was used. If the |τ| >Tcr, the correlation ranked as statistically significant.

Results

The epicardial fat thickness was associated with TIMP-1 plasma level (τ=0,71; Tcr=0,18) and MMP-9 (τ=0,65; Tcr=0,16). Among clinical factors weight was slightly associated with fat thickness (τ=0,33; Tcr=0,26). Besides, we found correlation of MMP-9, TIMP-1 with E/e' by TDI (τ=0,65; Tcr=0,16 and τ=0,56; Tcr=0,21, relatively); and with maximal systolic strain of lateral LV wall (τ=−0,37; Tcr=0,18 and τ=−0,44; Tcr=0,16, relatively) and interventricular septum (τ=−0,36; Tcr=0,18 and τ=−0,44; Tcr=0,16, relatively).

Conclusion

The epicardial fat thickness by CMR is significantly associated with myocardial fibrosis markers (MMP-9, TIMP-1) in patients with AF without structural heart disease. The increasing levels of MMP-9 and TIMP-1 are associated with LV local contractility disturbances by TDI in patients with AF. This association demonstrates the paracrine effect of EF, which could lead to atrial remodeling and formation AF substrate even in patients without valvular and ischemic heart disease and with normal or slightly enlarged LA

Funding Acknowledgement

Type of funding sources: None.
Arrhythmic risk stratification in patients with clinically-suspected left ventricular arrhythmogenic cardiomyopathy
Authors: Peretto G , Villatore A , Basso C , Della Bella P , Sala S
Published: October 2021

Background

Arrhythmic risk of patients with left ventricular arrhythmogenic cardiomyopathy (LVAC) is unpredictable.

Purpose

To identify risk facors associated with major ventricular tachyarrhythmias (VTA) in clinically-suspected LVAC patients.

Methods

We enrolled 127 consecutive patients (69% males, age 46±13 y, LVEF 54±7%) with clinically-suspected LVAC. All patients presented with either major (VT, VF) or minor VTA (NSVT, frequent VEB), and underwent extensive diagnostic workup to rule-out alternative diagnoses. Medical treatment and ICD implant were clinically-driven. Prospective follow-up was obtained via sequential 24h-Holter ECG (2–4/y) with or without continuous arrhythmia monitoring (ICD or implantable loop recorders, ILR). The primary endpoint was occurrence of major VTA (VT/VF/ICD therapy) by 24-month follow-up.

Results

At presentation, 56 (44%) and 71 patients (56%) had, respectively, major and minor VTA. Variants in desmosomal genes were identified in 7 of the 9 patients with clinically-indicated genetic test. Delayed gadolinium enhancement (DGE, average 23±12% of the LV mass) had anteroseptal distribution in 43 cases (34%). Monitoring strategy included ICD (n=64), ILR (n=33), or sequential Holer ECGs (n=30). By 24-month follow-up, major VTA occurred in 32 patients (25%). At univariable anlysis, major VTA onset (HR 16.8, 95% CI 5.4–52.2, p<0.001) and anteroseptal DGE (HR 3.0, 95% CI 1.3–6.9, p=0.010) were significantly associated with major VTA by 24-month follow-up. Among patients presenting with minor VTA, the only factor significantly associated with the primary endpoint was anteroseptal DGE (3/4 vs. 14/67, p=0.004).

Conclusion

Our preliminary experience suggests that, in patients with clinically-suspected LVAC, major VTA onset and anteroseptal DGE are relevant risk factors for major arrhythmic events by 24-month follow-up.

Funding Acknowledgement

Type of funding sources: None.
Frontal QRS/T angle can predict mortality in COVID-19 patients
Authors: Gunduz R , Yildiz B S
Published: October 2021

Aims

fQRS-T angle was investigated from general population including healthy people to patients who has hearth failure. It can predict mortality of myocarditis, ischemic cardiomyopathy, non-ischemic cardiomyopathy, idiopathic dilated cardiomyopathy and chronic heart failure in general population. There is no study in the literature that has been investigated for COVID-19 patients. The purpose of this retrospective multi-center study is to evaluate fQRS angle of COVID-19 patients for in-hospital mortality and need mechanical ventilation.

Methods and results

ECG was enrolled in 327 COVID-19 patients during admission and the fQRS angle calculated. Mechanical ventilation was needed for 119 patients and 110 of them died in hospital. Patients were divided into two groups according to their fQRS angle as fQRs>90° and fQRS≤90°. Percentages of mortality and need of MV according to fQRS angle were found 67.8% and 66.1% respectively in fQRs>90° group and 26.1%, 29.9% in fQRS≤90°group. Heart rate, SO2, fQRS, eGFR and CRP only were predictors for mortality in multivariable analysis. Mortality risk was increased 2.9-fold in univariate analysis and 1.6-fold in multivariate analysis for fQRS>90 patient group in respect to fQRS≤90 group.

Conclusion

In conclusion, a wide fQRS angle (>90°) was found as a predictor for mortality in-hospital and associated with the need for mechanical ventilation in COVID-19 patients.

Funding Acknowledgement

Type of funding sources: None. Mortality, need mechanical ventilationUnivariable and multivariable predictors
Usefulness of a smartphone-based event recorder for ambulatory patients presenting with palpitations
Authors: Salar Alcaraz M E , Buendia Santiago F , Flores Blanco P J , Cabrera Romero E , Fernandez Vazquez D , Vazquez Andres D J , Pascual Figal D A , Garcia Alberola A , Manzano Fernandez S
Published: October 2021

Background

Palpitations are a common complaint among patients seen by primary care physicians (16%). Recent technological advances have led to several novel electrocardiographic monitoring devices. AliveCor Kardia Mobile® (AliveCor, Inc., Mountain View, CA, USA) is a smartphone-based event recorder that allows take an electrocardiogram (ECG) recording during 30 seconds. The usefulness of this device has been studied in atrial fibrillation screening, however, its usefulness in the diagnosis of palpitations is not well known.

Objective

Evaluate the diagnostic yield of the AliveCor Kardia Mobile® device in unselected patients referred to the cardiologist for the study of palpitations.

Methods

Uni-centre retrospective study. From September 2018 to October 2020, consecutive patients with palpitations referred to cardiology department were included. After an initial evaluation it was decided monitoring ECG of these patients with this device if they had access to a compatible smartphone. They were instructed to record ECG when they had symptoms. ECG tracings and clinical characteristics were analysed.

Results

152 patients were included. Mean age 42±15 years, 68% female. Most of the patients did not have heart disease and about 25% had a history of anxiety-depressive syndrome (Table 1). After monitoring, 31 (20%) patients had rhythm disturbances during symptoms, 82 (54%) patients had no rhythm disturbances related to the symptoms and 39 (26%) patients had no symptoms. Table 2 shows the electrocardiographic findings. Patients with palpitations of arrhythmic origin were older and presented less anxiety/depression (Table 1). Age was the only independent predictor of palpitations of arrhythmic origin (OR, × year: 1.03, 95% CI 1.01–1.06; p=0.035).

Conclusions

The AliveCor Kardia Mobile® device is easy to use and diagnosed the aetiology of palpitations in a high proportion of patients (74%) referred for specialist evaluation.

Funding Acknowledgement

Type of funding sources: None.
Clustering of healthy lifestyle behaviors is associated with a lower incidence of adverse events in patients with newly diagnosed atrial fibrillation: a nationwide cohort study
Authors: Lee S R , Choi E K , Han K D , Oh S , Lip G Y H
Published: October 2021

Background

Although unhealthy or healthy lifestyle behaviors tend to be clustered, studies on the risk of clinical outcomes depending on how the lifestyle behaviors are managed after atrial fibrillation (AF) diagnosis remain limited.

Purpose

We aimed to evaluate the association between a cluster of healthy lifestyle behaviors and the risk of adverse outcomes in patients with AF.

Methods

Using the Korean National Insurance Service database, patients who were newly diagnosed as nonvalvular AF between 2009 and 2016 and received national health screening examination within 2-year after AF diagnosis were included. A healthy lifestyle behavior score (HLS) was calculated by assigning 1 point each for “non-current” smoking, for non-drinking, and for performing regular exercise from the self-reported questionnaire in health screening examinations. The primary outcome was defined as major adverse cardiovascular events (MACE), including ischemic stroke, myocardial infarction, and hospitalization for heart failure. The secondary outcomes included individual components of the primary composite outcome and all-cause death.

Results

A total of 208,662 patients were included and 7.1%, 22.7%, 58.6%, and 11.6% were HLS 0, 1, 2, and 3 group, respectively. After multivariable adjustment, patients with HLS 1, 2, and 3 were associated with lower risks of MACE compared to those with HLS 0 (adjusted hazard ratio [95% confidence interval]: 0.788 [0.762–0.855], 0.654 [0.604–0.708], and 0.579 [0.527–0.636], respectively) (Figure). Increased number of healthy lifestyle behaviors were associated with lower risks of ischemic stroke, hospitalization for heart failure, and all-cause death. The risk reduction of healthy lifestyle combinations was consistently observed in various subgroups, regardless of CHA2DS2-VASc score and oral anticoagulant use.

Conclusion

Increased number of healthy lifestyle behaviors were significantly associated with lower MACE and all-cause death risks in patients with new-onset AF. These findings support the promotion of a healthy lifestyle to reduce the risk of adverse events in AF patients.

Funding Acknowledgement

Type of funding sources: None.
The reinvented old player – an antazoline is effective in pharmacological cardioversion of atrial fibrillation
Authors: Miskowiec D , Dembowski T , Cwiek-Rebowska E , Qawoq H D , Zycinski P , Kupczynska K , Michalski B , Kasprzak J D
Published: October 2021

Introduction

Antazoline (ANT) is an old antihistaminic medication with antiarrhythmic properties. After intravenous administration ANT exerts rapid antiarrhythmic effect often resulting in conversion of atrial fibrillation (AF) to sinus rhythm (SR) and is widely used in Poland for this purpose in the last years. However, published data on its effectiveness, safety and clinical utility for rapid AF termination are limited and ANT is not recognized as a cardioversion drug.

Aim

To assess the real-world efficacy of ANT for pharmacological cardioversion of paroxysmal and persistent non-valvular AF.

Methods

Our single center, retrospective, observational study included patients (pts) with history paroxysmal or persistent AF episode lasting less than 6 months, in stable cardiopulmonary condition who were qualified for elective pharmacological cardioversion with intravenous ANT. The primary end-point was the conversion of AF to SR confirmed in electrocardiography (ECG) during the 6-hours observation.

Results

A total of 176 pts (mean age 68.4±12.0 years, 49% male) were enrolled into the study. In 93 patients (52%) AF duration was shorter than 48 hours and median AF duration time was 24 (7–432) hours. The overall success rate of pharmacological cardioversion of AF with intravenous ANT was 45.5% (80/176 pts). The mean used dose of ANT was 250.9±65.4mg. The subgroup analysis, regarding the AF duration, suggested the effectiveness of ANT mainly in in short-lasting AF (effectiveness of antazoline based cardioversion for AF lasting <48h vs others: 75.3% vs 12.0%, p<0.001). In multivariable logistic regression model AF duration (for every 24h in AF – OR=0.97; 95% CI 0.96–0.98), the left atrium antero-posterior diameter (OR=0.92; 95% CI 0.86–0.99) and the serum creatinine level (OR=0.15; 95% CI 0.03–0.73) were identified as independent predictors of antazoline based pharmacological cardioversion effectiveness, even after adjustment for comorbidities. The ROC curves revealed that the optimal cut-off value for AF duration time predicting ANT's effectiveness was 48h (AUC=0.876; 95% CI 0.815–0.922) – Figure 1. There were only one episode of bradycardia <45 bpm related to ANT administration.

Conclusions

Antazoline is effective and safe in rapid pharmacological cardioversion of paroxysmal AF, especially in the short-lasting AF (<48 hours) and in patients without the left atrium enlargement and significant renal disease.

Funding Acknowledgement

Type of funding sources: None. Figure 1. ROC curve analysis
Characterization of superresponders to cryoballoon ablation
Authors: Marti Almor J , Casteigt B , Jimenez-Lopez J , Conejos J , Valles E , Cladellas M
Published: October 2021

Background

Isolation of pulmonary veins is the cornerstone in the treatment of symptomatic atrial fibrillation rather with radiofrequency or cryo balloon. Recurrence rate is quite common in the long term follow up, clearly related to previosly described factors. Nevertheless some patients maintain sinus rhythm forever after the index ablation. The aim of this study is characterize this kind of patients (so called superresponders).

Methods

This is a Unicentric, retrospective, consecutive study including all patients summited for cryoablation in our hospital from January 2011 to September 2020. We looked for clinical, electrical, echocardiographic variables and those linked to the ablation procedure. A transversal FU to discard recurrences was done. A univariate and multivariate logistic regression was performed.

Results

We included 422 patients, 193 of them were finally excluded: 21 lost in the FU, 30 got radiofrequency ablation and 142 did not reach a minimum 5 years FU. About the 229 finally included, 85 (group 1) didn't have any recurrence during the FU, in front of 144 (group2) with recurrences. The univariate analysis showed that grup 1 patients were younger, the rate of hypertension, CHA2DS2VASc score, moderate sleep apnea, body mass index (BMI), p wave duration, and the size of left atrial was lower in grup 1 in front of patients of grup 2. Left ventricular ejection fraction was higher and the number of pulmonary veins in whom the temperature was lower than −40°C in grup 1 in front to grup 2. In the multivariate analysis the p wave duration: OR 0.92; 95% CI [0.89–0.94]; p<0.001, BMI kg/m2: OR 0.74; 95% CI [0.65–0.85]; p<0.001, a temperature <−40°C in all the targeted veins: OR 3.52 95% CI [1.45–8.54]; p=0.005 and SR on the ablation index day OR: 7.29; 95% CI [1.53–34.71]; p=0.012, maintained statistical significance.

Conclusions

In our series patients with a p wave duration, BMI, SR the ablation index day and achieving a temperature <−40°C in all the targeted veins, resulted as protective factors to maintain SR in the long term FU. An adequate selection of patients can improve results and optimize resources.

Funding Acknowledgement

Type of funding sources: None.
Location of sinoatrial artery and atria
Authors: Jantraprapavech K , Boonyapisit W
Published: October 2021

Background

Clinically manifested injury to the coronary arteries during catheter ablation procedures for atrial arrhythmias is rare. Injury to sinoatrial artery can cause sinus arrest and lead to permanent pacemaker implantation. Previous studies only described the anatomy of the artery but not the relation with atrium.

Objective

Our study aims to illustrate the course of the sinoatrial artery in relation to the atrium.

Methods

The images of coronary computed tomography angiography (CCTA) of 110 patients performed from June to September 2019 were reviewed.

Results

The sinus node was supplied by either single artery (98.18%) or dual blood supply (1.82%). Sinoatrial artery mostly originates from right coronary artery (56.25%), followed by left circumflex artery (42.85) and the aorta (0.90%).

When sinoatrial artery originated from right coronary artery or the aorta, it ran medially to the right atrium which its course vertically lied within 0.35±0.51 cm above and 1.45±0.63 cm below the superior vena cava-right atrium junction. The artery then passed between left atrium and right atrium, which 21.88% of the course ran within 0.5 cm from the right upper pulmonary vein ostium.

When sinoatrial artery arises from left circumflex artery, 95.83% of this pathing were anterior to left atrial appendage. Only 4.17% went along anteriorly to the left upper pulmonary vein. Most of sinoatrial artery that arises from left circumflex artery (97.92%) ran pass the upper one-third of left atrium, then ran toward posteroseptum of right atrium. This course vertically lied within 0.51±0.73 cm above and 0.67±0.83 cm below the superior vena cava-right atrium junction. Additionally, we found that 39.58% of sinoatrial artery arises from left circumflex artery course lied within 0.5 cm from right upper pulmonary vein ostium.

Conclusion

Exceeding precaution while performing radiofrequency ablation at anterior upper one-third left atrium, base of left atrium appendage, upper part septal wall of right atrium and right upper pulmonary vein ostium should be established to prevent sinoatrial artery injury.

Funding Acknowledgement

Type of funding sources: None.
A mixed-reality holographic viewing platform enabling interaction with 3D electroanatomical maps using the HoloLens
Authors: Malaweera A , Jogi R , Wright M , O'Neill M , Williams S
Published: October 2021

Introduction

Three dimensional (3D) electroanatomical maps (EAMs) created during electrophysiology procedures are traditionally displayed on 2D monitors connected to mapping systems. This has limitations, such as the lack of interaction with EAMs, the need for another user to control them, and the size of EAM displayed, which is limited by the resolution of these monitors. To overcome these, we created a novel technology to display EAMs on a mixed reality (MR) platform.

Methods

We used the Microsoft® HoloLens to create this MR platform. Studies from patients who had already undergone catheter ablation for atrial fibrillation, where EAMs of the left atria had been generated using different mapping systems (CARTO®, Rhythmia™ and EnSite Precision™) were utilised. These EAMs consisting of 3D coordinates and annotations (e.g. voltage & activation times) were exported from the mapping system. EAMs were then compiled and transferred to the HoloLens using custom-developed functions on Unity©, Microsoft® C# and VisualStudio. Subsequently, feedback was obtained from 3 independent electrophysiologists on this technology.

Results

We successfully exported the EAMs generated on CARTO®, Rhythmia™ and EnSite Precision™ mapping systems as holograms on to the HoloLens (Figure). Positive feedback included themes such as 1) the ability to use hand gestures and voice commands to interact with EAMs independent of another user unlike traditional cardiac mapping systems 2) offering an interactive 3D holographic experience whilst preserving the operators' physical interaction in the cardiac catheter lab 3) the capacity to better appreciate 3D geometry of EAMs in comparison to 2D monitors. The challenge of wearing a headset during long procedures was perceived as a disadvantage.

Conclusion

This technology, which can be used with any mapping system, is currently optimised for offline display. Our software will be made available as an opensource teaching and simulation tool. Users will be able to explore EAMs for research, planning complex cases and immersive learning. The future directions will include extending this toolkit for real-time cardiac mapping with catheter localisation, and could potentially be translated to other cardiac imaging modalities.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Cardiovascular diseases charitable fund (CDCF) at Guy's and St Thomas' NHS Foundation Trust. Process of creating Holograms of EAMsVoltage map of left atrium as a Hologram
Peripheral vascular access from the arms for invasive cardiac investigation using ultrasound guidance
Authors: Kadiwar S , Griffiths J , Ailoaei S , Barton B , Samchkuashvili N , Adams L , Browne S , Paynter A , Kempny A , Ernst S
Published: October 2021

Introduction

Vascular access for invasive cardiac investigations has traditionally been gained from the femoral vessels, however, a “radial-first” approach has become increasingly popular for coronary interventions [1]. Transradial access has shown lower complication rates, shorter admission times, and reduced healthcare costs for coronary interventions [4]. A “superior” approach via the jugular and subclavian veins have been reported for electrophysiology (EP) studies and radiofrequency catheter ablation (RFCA) but is associated with an increased risk of complications such as pneumo- and haemothorax [9].

Purpose

EP procedures often require the use of both venous and arterial catheters, and the potential advantage of non-femoral peripheral access is yet to be investigated. This study was performed to provide comprehensive anatomical evidence that the vessels of the arms are suitable for use during EP procedures, as assessed by vascular ultrasound.

Methods

A portable ultrasound device was used to measure the diameter of the brachial artery, brachial vein, basilic vein & cephalic vein on the left and right upper limbs of 63 healthy adult volunteers. Measurements were also taken of the circumference at the elbow and at the mid-bicep level on both arms. A subgroup of 15 volunteers had additional measurements taken of the same veins and artery on both arms with a tourniquet at the upper bicep level.

Results

The basilic vein was found to have the largest diameter with a median of 4.6 mm and 4.5 mm (right and left diameter, respectively), followed by the cephalic (median of 3.1 and 3.0 mm) and the brachial vein (median of 2.8 mm for both arms). 100% of volunteers had at least one vein that was equal to a 3 mm diameter (which would allow for a 8F sheath insertion), with 98% having 2 suitable veins and >80% having 3 suitable venous vessels. More than 90% had a suitable diameter of more than 3 mm for both the right and left brachial artery. There was significant correlation between gender, and basilic vein and brachial artery diameters. There was no correlation between BMI, height, weight and elbow or bicep circumference.

Conclusion

To our knowledge, this is the first study to investigate the feasibility of adopting peripheral access in the electrophysiology lab. 100% of volunteers examined had one vein which was at least 3mm in size and would be suitable for 8F sheath insertion. We demonstrate the anatomic evidence that the vessels in the arm are capable of housing the size of sheath and catheters commonly used in the EP lab.

Funding Acknowledgement

Type of funding sources: None. Figure 2. measurementsFigure 3. Vessel diameters
Comparing predictors of permanent pacemaker insertion after TAVR in new-generation versus early generation heart valves
Authors: Gupta R , Mahajan S , Malik A , Mehta S , Patel N
Published: October 2021

Introduction

Transcatheter Aortic Valve Replacement (TAVR) has emerged as the standard of care for patient with severe aortic stenosis. Conduction abnormalities leading to permanent pacemaker (PPM) implantation is one of the most common complication after TAVR. Newer generation valves (NGV) such as Sapien S3, XT and Evolut are widely being used in real time practice. The aim of this analysis is to compare the predictors associated with increased risk of PPM implantation after TAVR in newer generation valves (NGV) as compared to older generation valves (OGV).

Methods

A comprehensive literature search was performed in PubMed, Embase, and Cochrane to identify relevant trials. Summary effects were calculated using a DerSimonian and Laird random-effects model as odds ratio with 95% confidence intervals for all the clinical endpoints.

Results

18 observational studies with 16,004 patients were identified. The incidence of PPM implantation after TAVR in our analysis was 8.9%. For the NGV, right bundle branch block (RBBB) and atrioventricular (AV) block were independent predictors of PPM insertion after TAVR. Baseline heart rate, presence of atrial fibrillation, and baseline intraventricular conduction delay were not significant predictors. However, for the OGV, risk of PPM implantation after TAVR was higher in presence of RBBB, depth of implant, valve size/annulus size, presence of atrial fibrillation and post-procedure AV block.

Conclusions

Our analysis identified 2 factors that were significantly associated with increased risk of PPM insertion after TAVR in NGV compared to 6 factors with OGV. With the increasing physician expertise with TAVI and use of NGV, the incidence of post TAVR PPM insertion has reduced but baseline RBBB and AV conduction block still continue to be significant predictors of increased PPM insertion after TAVR.

Funding Acknowledgement

Type of funding sources: None.