bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automatic ECG-based detection of left ventricular hypertrophy and its predictive value in haemodialysis patients
Authors: Letz Theresa , Hörandtner Carina , Braunisch Matthias C , Gundel Peter , Matschkal Julia , Bachler Martin , Lorenz Georg , Körner Andreas , Schaller Carolin , Lattermann Moritz , Holzinger Andreas , Heemann Uwe , Wassertheurer Siegfried , Schmaderer Christoph , Mayer Christopher C 
Published: June 2023

Abstract

Objective. Left ventricular hypertrophy (LVH) is one of the most severe risk factors in patients with end-stage kidney disease (ESKD) regarding all-cause and cardiovascular mortality. It contributes to the risk of sudden cardiac death which accounts for approximately 25% of deaths in ESKD patients. Electrocardiography (ECG) is the least expensive way to assess whether a patient has LVH, but manual annotation is cumbersome. Thus, an automated approach has been developed to derive ECG-based LVH parameters. The aim of the current study is to compare automatic to manual measurements and to investigate their predictive value for cardiovascular and all-cause mortality. Approach. From the 12-lead 24 h ECG measurements of 301 ESKD patients undergoing haemodialysis, three different LVH parameters were calculated. Peguero-Lo Presti voltage, Cornell voltage, and Sokolow–Lyon voltage were automatically derived and compared to the manual annotations. To determine the agreement between manual and automatic measurements and their predictive value, Bland–Altman plots were created and Cox regression analysis for cardiovascular and all-cause mortality was performed. Main results. The median values for the automatic assessment were: Peguero-Lo Presti voltage 1.76 mV (IQR 1.29–2.55), Cornell voltage 1.14 mV (IQR 0.721–1.66), and Sokolow–Lyon voltage 1.66 mV (IQR 1.08–2.23). The mean differences when compared to the manual measurements were −0.027 mV (0.21 SD), 0.027 mV (0.13 SD) and −0.025 mV (0.24 SD) for Peguero-Lo Presti, Cornell, and Sokolow–Lyon voltage, respectively. The categorial LVH detection based on pre-defined thresholds differed in only 13 cases for all indices between manual and automatic assessment. Proportional hazard ratios only differed slightly in categorial LVH detection between manually and automatically determined LVH parameters; no differences could be found for continuous parameters. Significance. This study provides evidence that automatic algorithms can be as reliable in LVH parameter assessment and risk prediction as manual measurements in ESKD patients undergoing haemodialysis.
A unified framework for multi-lead ECG characterization using Laplacian Eigenmaps
Authors: Villa Amalia , Ingelaere Sebastian , Jacobs Ben , Vandenberk Bert , Van Huffel Sabine , Willems Rik , Varon Carolina 
Published: June 2023

Abstract

Background. The analysis of multi-lead electrocardiographic (ECG) signals requires integrating the information derived from each lead to reach clinically relevant conclusions. This analysis could benefit from data-driven methods compacting the information in those leads into lower-dimensional representations (i.e. 2 or 3 dimensions instead of 12). Objective. We propose Laplacian Eigenmaps (LE) to create a unified framework where ECGs from different subjects can be compared and their abnormalities are enhanced. Approach. We conceive a normal reference ECG space based on LE, calculated using signals of healthy subjects in sinus rhythm. Signals from new subjects can be mapped onto this reference space creating a loop per heartbeat that captures ECG abnormalities. A set of parameters, based on distance metrics and on the shape of loops, are proposed to quantify the differences between subjects. Main results. This methodology was applied to find structural and arrhythmogenic changes in the ECG. The LE framework consistently captured the characteristics of healthy ECGs, confirming that normal signals behaved similarly in the LE space. Significant differences between normal signals, and those from patients with ischemic heart disease or dilated cardiomyopathy were detected. In contrast, LE biomarkers did not identify differences between patients with cardiomyopathy and a history of ventricular arrhythmia and their matched controls. Significance. This LE unified framework offers a new representation of multi-lead signals, reducing dimensionality while enhancing imperceptible abnormalities and enabling the comparison of signals of different subjects.
Actuation performances and microscopic mechanism of a stimuli-responsive artificial muscle based on the chelation of sodium alginate with CaI2·4H2O
Authors: Yang Junjie , Jiang Zhen , Wang Siyong , Yao Jintong , Yu Tao , Wei Kang , Fang Mingjian 
Published: June 2023

Abstract
With the popularization of energy conservation and environmental protection, a stimuli-responsive artificial muscle (SRAM) prepared by green process of the chelation of sodium alginate (SA) with calcium iodide tetrahydrate (CaI2·4H2O), provides new ideas and prospects for the development and application of smart artificial muscles. In this paper, actuation performances including force density (Fρ
, mN/g), working life (τ, s), rise time (τ
r, s) and response speed (V
F, mN/g·s) of the SRAM with different concentrations of CaI2·4H2O was researched through the test platform of electrically bending force. Furthermore, the microscopic mechanism on mechanical and electrochemical characteristics of the SRAM was analyzed and verified comprehensively by microstructure, energy dispersive spectroscopy, ion channel, infrared spectroscopy and diffraction of x-rays. The experimental results were demonstrated that when the concentration of CaI2·4H2O was within the range of 1.5 g l−1–2.0 g l−1, the SRAM achieved optimal modification, where at 1.5 g l−1 CaI2·4H2O, its specific capacitance and τ were both the maximum values of 93.7 mF g−1 and 1080 s, but internal resistance was the minimum of 3.09 Ω; at 2.0 g l−1 CaI2·4H2O, the Fρ, V
F, elastic modulus, yield strength and ion channel of the SRAM reached the largest values of 22.807 mN g−1, 0.1046 mN g−1·s, 20 MPa, 0.18091 MPa and 60.2%, respectively, but τ
r obtained the lest of 98 s. Because after being chelated by CaI2·4H2O, the α-L-guluronic blocks in SA molecular chains coagulated with Ca2+ ions, making the synergy between molecular chains of the SRAM stronger, thus forming a three-dimensional ‘egg box’ network structure of polymeric hydrogel.
Effects of aberrations on isoSTED microscopy
Authors: Lee Jeongjae , Lee Dong-Ryoung 
Published: June 2023

Abstract
Aberrations are inevitable in optical microscopes and affect the image quality. In STED microscopy, the optical resolution is especially dominated by the performance of depletion pattern. To quench fluorescence only in the periphery of the excitation focus, the depletion focus ideally has a zero-intensity point that is surrounded by a high-intensity crest. Otherwise, distortion of the depletion beam causes unwanted fluorescence inhibition. The influence of aberrations on isoSTED microscopy differs from that on STED microscopy because isoSTED microscopy generates a more complicated shape of the depletion focal spot with two opposing objectives which have different focusing properties. We present analysis that elucidates the effects on the shape, the central minimum intensity, and the peak intensity of the isoSTED pattern regarding primary aberrations such as astigmatism, coma, and spherical aberration when those aberrations are added in the shared beam path and each beam path in the 4Pi-cavity. The simulation results demonstrate significant resolution degradation (>160%; defined as the focal volume) for the aberrations with root mean square wavefront errors of 0.5 rad.
Dipole anisotropy in gravitational wave source distribution
Authors: Kashyap Gopal , Singh Naveen K. , Phukon Khun Sang , Caudill Sarah , Jain Pankaj 
Published: June 2023

Abstract
Our local motion with respect to the cosmic frame of rest is believed to be dominantly responsible for the observed dipole anisotropy in the Cosmic Microwave Background Radiation (CMBR). We study the effect of this motion on the sky distribution of gravitational
wave (GW) sources. We determine the resulting dipole anisotropy in GW source number counts, mass weighted number counts, which we refer to as mass intensity,
and mean mass per source. The mass M dependence of the number density n(M) distribution of BBH is taken directly from the data. We also test the anisotropy in the observable mean mass per source along the direction of the CMB dipole. The current data sample is relatively small and consistent with isotropy. The number of sources required for this test is likely to become available in near future.
Development of a plasma-based 3D printing system for enhancing the biocompatibility of 3D scaffold
Authors: Kim Seung Hyeon , Lee Jae Seo , Lee Sang Jin , Nah Haram , Min Sung Jun , Moon Ho Jin , Bang Jae Beum , Kim Han-Jun , Kim Won Jong , Kwon Il Keun , Heo Dong Nyoung 
Published: June 2023

Abstract
Fused deposition modeling (FDM) is a three-dimensional (3D) printing technology typically used in tissue engineering. However, 3D-printed row scaffolds manufactured using material extrusion techniques have low cell affinity on the surface and an insufficient biocompatible environment for desirable tissue regeneration. Thus, in this study, plasma treatment was used to render surface modification for enhancing the biocompatibility of 3D-printed scaffolds. We designed a plasma-based 3D printing system with dual heads comprising a plasma device and a regular 3D FDM printer head for a layer-by-layer nitrogen plasma treatment. Accordingly, the wettability, roughness, and protein adsorption capability of the 3D-printed scaffold significantly increased with the plasma treatment time. Hence, the layer-by-layer plasma-treated (LBLT) scaffold exhibited significantly enhanced cell adhesion and proliferation in an in vitro assay. Furthermore, the LBLT scaffold demonstrated a higher tissue infiltration and lower collagen encapsulation than those demonstrated by a non-plasma-treated scaffold in an in vivo assay. Our approach has great potential for various tissue-engineering applications via the adjustment of gas or precursor levels. In particular, this system can fabricate scaffolds capable of holding a biocompatible surface on an entire 3D-printed strut. Thus, our one-step 3D printing approach is a promising platform to overcome the limitations of current biocompatible 3D scaffold engineering.
“Sufficient for the day is its own trouble”: Medicalizing Risk and the Way of Jesus
Authors: Curlin Farr 
Published: June 2023

AbstractIt is common wisdom that today’s medicine focuses too much on treating those who are sick and too little on preventing the sickness in the first place. This essay proposes that Jesus’ teaching in the Sermon on the Mount challenges that assumption and the preventive medicine to which it has given rise. In light of Jesus’ teaching, the essay identifies four apparent problems with much of preventive medicine. It then offers four heuristics that might form a basic Christian logic for medicalizing risk—for discerning when and why it would be fitting, wise, and faithful for Christians to make use of medicine to avoid future illness and death.
Classifying hypertension mediated left ventricular hypertrophy phenotypes from the 12-lead electrocardiogram using machine learning
Authors: Naderi H , Ramirez J , Van Duijvenboden S , Ruiz Pujadas E , Aung N , Wang L , Chahal C A A , Lekadir K , Petersen S E , Munroe P B 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Pat Merriman Clinical Research Training Fellowship

Background
Hypertension is the commonest cause of left ventricular hypertrophy (LVH), an established independent predictor of cardiovascular morbidity and mortality. Four distinct LVH phenotypes with varying prognostic implications have been reported using cardiac magnetic resonance (CMR) LV mass to volume ratio: normal LV, LV remodelling, eccentric LVH and concentric LVH. Current electrocardiogram (ECG) criteria can detect LVH but their ability to differentiate between hypertension mediated LVH phenotypes is unknown.

Purpose
The aim of this study was to classify hypertension mediated LVH phenotypes using 12-lead electrocardiogram (ECG) and clinical data for cost-effective patient stratification.

Methods
24,535 hypertensive participants from UK Biobank imaging study were categorised into the CMR-defined LVH phenotypes. ECG biomarkers with a physiological association with LVH (including QRS biomarkers, Sokolow-Lyon and Cornell voltage) were extracted from the 12-lead ECG of each participant using in-house algorithms. Vascular risk factors known to be associated with LVH were also ascertained from the clinical data of each participant. Classification models integrating ECG biomarkers and clinical data were built using logistic regression, support vector machine (SVM) and random forest (RF). The dataset was split into 80% train and 20% test sets for performance measurement. Ten-fold cross validation was applied and the training set was downsampled to the minority class.

Results
Among the participants (mean age ± standard deviation 65.3 ± 7.4 years), 23,312 (95.0%) had normal LV, 900 (3.7%) LV remodelling, 220 (0.8%) eccentric LVH and 103 (0.4%) concentric LVH. R wave amplitude V5, S wave amplitude V3 and QT duration V6 (P&lt;0.001) were the top ECG biomarkers and systolic blood pressure (p&lt;0.001) the top clinical predictor of LVH phenotypes (Figure 1). Classification with logistic regression had an accuracy of 77% (sensitivity 55%, specificity 85%, Area under the receiver operator curve [AUC] 0.76), SVM 80% accuracy (sensitivity 61%, specificity 87%, AUC 0.75) and RF 75% accuracy (sensitivity 49%, specificity 83%, AUC 0.75). ECG biomarkers enhanced model performance of all classifiers, compared to using clinical data alone.

Conclusion
A combination of automatically extracted ECG biomarkers and clinical data were able to discriminate the hypertension mediated LVH phenotypes. An advanced classification approach improves selection of hypertensive patients with LVH, thereby adding prognostic value to traditional risk models. We are currently validating our findings in an external population and using deep learning for comparison.
False lumen flow dynamics and partial thrombosis in patients with chronic aortic dissection of the descending aorta: a 4D flow CMR study
Authors: Ruiz Munoz A , Guala A , Dux-Santoy L , Teixido-Tura G , Galian-Gay L , Garrido-Oliver J , Carrasco-Poves A , Morales A , Valente F , Cuellar-Calabria H , Johnson K , Wieben O , Evangelista A , Ferreira-Gonzalez I , Rodriguez-Palomares J F 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Spanish Ministry of Science, Innovation, and Universities

Background
Partial thrombosis of the false lumen (FL) in patients with chronic aortic dissection (AD) of the descending aorta has recently been associated with poor outcomes (1). However, four-dimensional phase-contrast cardiovascular magnetic resonance (4D flow CMR) studies analyzing flow dynamics and biomechanics in the FL and their relationship with partial thrombosis are lacking.

Purpose
This study aimed to compare FL flow dynamics and biomechanics between patients with non- and partially-thrombosed FL.

Methods
Patients with a chronic (&gt;3 months after the acute event), non-thrombosed or partially-thrombosed FL in the descending aorta after an AD underwent an imaging follow-up including a magnetic resonance angiography (MRA) and a 4D flow CMR study. FL thrombosis was quantified as the ratio of thrombus volume and FL volume on MRA. Forward systolic and diastolic flow, and wall shear stress (WSS) were calculated at 8 equidistant planes covering the FL descending aorta from the pulmonary bifurcation to the diaphragmatic level, and averaged values were used (1,2). Maximum kinetic energy (KE), maximum acceleration and flow stasis were quantified in a volume covering the same region of the descending aorta (1). Aortic stiffness in the FL was assessed in terms of pulse wave velocity (PWV), which was calculated from the third supraortic trunk to the diaphragmatic level (3).

Results
Sixty-five patients with a complete imaging protocol were included in the study. The FL was non thrombosed in 34 patients and partially thrombosed in 31 patients, which presented with the 21 ± 13 % of the FL volume occupied by thrombus. Demographics and clinical data, and flow dynamic and biomechanical parameters of these patients are shown in Table 1. Partial thrombosis of the false lumen was associated with a reduction in the amount and energy of flow in the FL (reduced forward systolic flow, KE and acceleration (Figure 1B-D, respectively)), and a more stagnated flow in the FL (increased flow stasis (Figure 1E)). Axial WSS showed a tendency to be lower in the partial-thrombosis group compared to the no-thrombosis group (Figure 1F), while PWV were similar in both of them.

Conclusion
In patients with chronic AD of the descending aorta, false lumen axial wall shear stress, kinetic energy, and flow acceleration and stasis proved to be the main discriminators between no and partial thrombosis of the false lumen.
Changes in left ventricular strain and cardiac biomarkers in a six-year prospective follow-up after breast cancer radiotherapy
Authors: Vaarpu M , Moisander M , Lehmonen L , Kivisto S , Skytta T , Kellokumpu-Lehtinen P L , Virtanen V , Huhtala H , Raatikainen P , Tuohinen S 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Finnish public grant

Aims
Breast cancer radiotherapy (RT) can lead to slowly developing cardiac dysfunction and increased incidence of heart failure with preserved ejection fraction (HFpEF). In fact, the risk for HFpEF is shown to be 16-fold after chest radiotherapy. We aimed to study the changes in left ventricular strain six years after radiotherapy as well as changes in cardiac biomarkers during the follow-up.

Methods
Early left-sided breast cancer patients (n=31) were prospectively followed-up for six years after RT. Left ventricular strain analysis and pro-brain natriuretic peptide (proBNP) tests were performed at baseline, after RT and at three-year and six-year controls. In addition, cardiac magnetic resonance imaging (CMR) was performed at the six-year follow-up. The results were compared with cardiac RT doses.

Results
Global longitudinal strain (GLS) declined only modestly from baseline 17.9±4.1% to 17.6±2.7% at six-year control (p = 0.731) while apical regions showed significant decline from baseline 24.6±6.6% to 19.8±3.5% at six-year control (p&lt;0.001). ProBNP increased from baseline 63.0 [37.0, 124.0] ng/l to 98.0 [50.0, 215.0] ng/l at six-year follow-up (p = 0.022). Patients with (n=14) and without (n=16) worsening of apical strain and increase in proBNP had maximal left ventricular radiation doses 46.9±4.8 Gy versus 40.1±12.9 Gy (p = 0.049), respectively. Lower values in CMR strain were concentrated in the apical regions with an association with regional RT doses. Each 1 Gy of regional radiation dose decreased local regional strain value in CMR by 0.356 % [95%CI; 0.244, 0.468] (p&lt;0.001).

Conclusions
A significant increase in proBNP and a significant decrease in apical strain were observed after RT in six-year follow-up. A higher left ventricular maximal radiation dose was significantly associated with worsening in apical strain and proBNP. In addition, a worse regional strain values in CMR had a dose-dependent association with corresponding RT doses. These results indicate that even contemporary breast cancer RT induces progressive cardiac changes.
Left atrial strain predicts outcome in cardiovascular diseases: a systematic review and meta-analysis
Authors: Rizzetto F , Maffeis C , Mandurino-Mirizzi A , De Silvestri A , Ghio S , Rossi A 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Aims
The prognostic role of left atrial volume is well established in a variety of cardiovascular conditions but left atrial enlargement may occur at a relatively advanced stage of disease. Left atrial function measured by atrial strain could represent an early marker of disease. The aim of this meta-analysis was to evaluate the predictive value of left atrial strain (LAS) for major cardiovascular events in patients with cardiovascular diseases.

Methods and results
We systematically searched PUBMED, COCHRANE Central Register of Controlled Trials and WEB OF SCIENCE (WoS) up to May 2021 to identify studies including the relationship between LAS measured by speckle-tracking echocardiography and cardiovascular outcome (mortality and hospitalization for heart failure). A meta-analysis following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) framework was conducted. Nine reports including 6021 patients were eligible. The meta-analysis revealed that LAS predicted outcome in a population with a variety of cardiovascular conditions, that is heart failure, valvular heart disease, ischemic heart disease and left ventricular hypertrophy (HR 0.95; 95% CI 0.91–0.98). The result was confirmed in patients with heart failure (HR, 0.74; 95% CI, 0.55–1) or valvular heart disease (HR, 0.94; 95% CI, 0.90-.97).

Conclusions
LAS represents a powerful predictor of major cardiovascular events in patients with different cardiovascular diseases. Patients having lower values of LAS are at increased risk of mortality and hospitalizations for HF.
Diagnostic and prognostic value of stress CMR imaging to evaluate stable chest pain: a twenty-year meta-analysis
Authors: Bisaccia G , Ricci F , Khanji M Y , Gallina S , Petersen S E , Bucciarelli-Ducci C 
Published: June 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Assessment of inducible ischemia with stress cardiovascular magnetic resonance (CMR) is recommended in patients with chest pain and intermediate or high pre-test probability of coronary artery disease (CAD). We aimed to provide a contemporary quantitative data synthesis on diagnostic accuracy and prognostic value of stress CMR in patients with stable chest pain syndromes.

Methods
We performed a prespecified systematic review and meta-analysis of studies published over the last twenty years on the diagnostic and prognostic value of stress CMR (PROSPERO: CRD42022299275). We measured pooled diagnostic indicators, including diagnostic odds ratio (DOR), sensitivity, specificity, area under the curve (AUC), and summary effect size indicators, including odds ratios (ORs) and cumulative annualized event rates (AERs) for all-cause death, cardiovascular death and major adverse cardiac events (MACE).

Results
We identified 33 diagnostic studies pooling 7,815 individuals (mean age, 62 years, 62% males) and 31 prognostic studies pooling 67,080 patients (mean age, 62 years; 57% males; mean follow-up 3.5 years for a total of 381,357 person-years). Stress CMR yielded a pooled DOR of 26.4 (95%CI:10.6–65.9), a sensitivity of 81% (95%CI:68–89%), a specificity of 86% (95%CI:75–93%), and an AUC of 0.84 (95%CI:0.77–0.89) for the detection of functionally obstructive CAD with fractional flow reserve as the reference test. In subgroup analysis, 3 Tesla imaging yielded higher diagnostic accuracy achieving a DOR of 33.2. Presence of stress-inducible ischemia was associated with higher all-cause mortality (OR:2.0; 95%CI:1.7–2.3), cardiovascular mortality (OR:6.4; 95%CI:4.5–9.1), and increased risk of MACE (OR:5.3; 95%CI:4.0–7.0). AERs for cardiovascular death and MACE were &lt; 1% in patients without stress-inducible ischemia.

Conclusion
Stress CMR yields high diagnostic accuracy and delivers robust prognostication in patients with stable chest pain and known or suspected CAD, particularly with 3 Tesla imaging. While inducible ischemia portends excess mortality and increased risk of MACE, a negative stress CMR indicates a very low risk of future cardiovascular events, with a warranty period of at least 3.5 years.