bluuebunny/crossref_metadata_2025 huggingface dataset:
Chinese–Russian distance interpreting landscape: a local perspective
Authors: Krasnopeyeva Ekaterina , Volchkova Anastasiya
Published: February 2022

This paper discusses the Chinese–Russian interpreters’ views on the adoption of distance interpreting (DI) technology in the local Russian context. From the intergovernmental to the people-topeople level, the Sino-Russian relationship has been developing as a strategic partnership. Due to travel restrictions and other pandemic containment measures, the demand for virtual communication technology and remote interpreting has been on the rise, which highlighted a variety of implications for the interpreting profession. We present the results of a series of interviews with Chinese–Russian interpreters from Moscow and Chelyabinsk, Russia (n=6), accompanied by a small-scale online survey (n=26). The exploratory study focuses on the interpreters’ experience with technology, and on their perception of DI in general and video remote interpreting in particular. The results suggest that the common DI scenarios in the local Chinese– Russian interpreting market (Chelyabinsk region) include video-mediated and over-the-phone consecutive interpreting in business and education settings. The study also reveals an overall positive attitude to the DI technology among the surveyed interpreters, despite such reported challenges as psychological discomfort, connection problems and technical difficulties on the clients’ part, which often lead to new responsibilities of an interpreter.
Herzrhythmusstörungen bei Frauen
Authors: Scheurlen Cornelia , Steven Daniel , Sultan Arian
Published: February 2022

Bei Herzrhythmusstörungen zeigen sich deutliche geschlechtsspezifische Unterschiede
zwischen Männern und Frauen. Diese Unterschiede reichen von der Physiologie auf zellulärer
Ebene über unterschiedliche Symptome bis hin zum Zugang und Erfolg einer Therapie. In den
großen randomisierten Studien sind Frauen fast immer unterrepräsentiert. Aufgrund des
zunehmenden Bewusstseins über diese signifikanten Unterschiede wurde vor einigen Jahren
ein Positionspapier der EHRA (European Heart Rhythm Association) veröffentlicht, auf
welches im folgenden Artikel Bezug genommen wird.
Geschlechtsunterschiede bei Herzinsuffizienz – Behandlung und
Prognose
Authors: Angermann Christiane E. , Aßmus Birgit
Published: February 2022

Weltweit sind bei Frauen kardiovaskuläre Erkrankungen die Haupttodesursache. Bei
Ätiologie, Epidemiologie, Pathophysiologie, Symptomatik und Komorbiditäten der
Herzinsuffizienz (HI) sowie bei Wirkungen und Nebenwirkungen von Therapiemaßnahmen und der
Prognose gibt es relevante Geschlechtsunterschiede. Trotzdem sind in klinischen Studien
Frauen als Teilnehmerinnen bzw. in der Studienleitung unterrepräsentiert. Sekundäre
Analysen aus Therapiestudien legen Geschlechtsunterschiede bei Wirksamkeit,
Nebenwirkungsprofil und optimaler Dosierung von Medikamenten und beim Nutzen von
Device-Therapien nahe. Prospektive Studiendesigns mit dem Ziel, Geschlechtsunterschiede zu
herauszuarbeiten, gibt es kaum, und Leitlinienempfehlungen sind meist geschlechtsneutral.
Dieser Übersichtsartikel beschreibt Unterschiede bei Behandlungseffekten, Verfügbarkeit
von Therapien und Krankheitsprognose, beleuchtet Wissenslücken und zeigt, wo
Handlungsbedarf besteht, um die Situation von Frauen mit HI zu verbessern.
Verletzungen und Überlastungsschäden der
großen Apophysen
Authors: Gaulrapp Hartmut , Lackner Theresa Anna , Mellerowicz Holger
Published: February 2022

Apophysen sind sekundär verknöchernde Knochenvorsprünge, an
denen Sehnen ansetzen. Ihr anatomischer Aufbau entspricht weitgehend dem von
Epiphysen und deren Wachstumsfugen, sie tragen jedoch nicht zum
Längenwachstum bei. Apophysen gehören zu den bei Kindern und
Jugendlichen am häufigsten verletzten Strukturen. Apophysenausrisse werden
unter Sehnenrissen subsumiert (ICD S76.-), Apophysenerkrankungen unter juvenilen
Osteochondrosen (M92.-).
Colorectal Surgery in Critically Unwell Patients: A Multidisciplinary Approach
Authors: Subramaniam Ashwin , Wengritzky Robert , Skinner Stewart , Shekar Kiran
Published: February 2022

A proportion of patients require critical care support following elective or urgent colorectal procedures. Similarly, critically ill patients in intensive care units may also need colorectal surgery on occasions. This patient population is increasing in some jurisdictions given an aging population and increasing societal expectations. As such, this population often includes elderly, frail patients or patients with significant comorbidities. Careful stratification of operative risks including the need for prolonged intensive care support should be part of the consenting process. In high-risk patients, especially in setting of unplanned surgery, treatment goals should be clearly defined, and appropriate ceiling of care should be established to minimize care that is not in the best interest of the patient. In this article we describe approaches to critically unwell patients requiring colorectal surgery and how a multidisciplinary approach with proactive intensive care involvement can help achieve the best outcomes for these patients.
The Dynamic History of the Ophthalmology Residency Matching Program
Authors: Blodi Christopher F. , Krueger Ronald R.
Published: February 2022

Background The ophthalmology residency matching program is the first successful medical specialty match, dating back to 1979. This article reviews the impetus for starting the match and the roles that ophthalmologists Bruce Spivey, MD, and August Colenbrander, MD, PhD, played in establishing the match and developing the machinery to make it possible. Challenges to the match's operations over the years have improved the process.

Objective This article aims to research the roles of key individuals and institutions in establishing and maintaining the ophthalmology residency matching program.

Methods Oral and written interviews with key participants in establishing and maintaining the match were conducted. Primary and secondary written materials were reviewed.

Results Two physicians played key roles in establishing the ophthalmology residency matching program. Bruce Spivey, MD, spearheaded the drive to persuade the Association of University Professors of Ophthalmology (AUPO) to support and sponsor the match. August Colenbrander, MD, PhD, created the original match algorithm and single-handedly ran the match process in the early years. Obstacles were overcome, including resistance from the Association of American Medical College's National Resident Matching Program, a challenge to the validity of the algorithm, and the threat that antitrust laws might prohibit all graduate medical education residency match programs. The ophthalmology match evolved over time to become a more formal entity, the San Francisco Matching Program (SF Match). With continued support of the AUPO, the process of matching applicants to residency programs has flourished despite contemporary challenges related to electronic applications and social media.

Conclusion The ophthalmology residency matching program has benefited applicants and teaching programs for more than four decades due to visionary founders, ongoing support of the AUPO, and strong leadership within SF Match.
Medication Management of Neuropsychiatric Symptoms in Neurological Conditions: A Dimensional Transdiagnostic Approach
Authors: Anderson Jordan R. , Schrift Michael
Published: February 2022

Neuropsychiatric symptoms are prevalent in neurologic practice, but their complexity makes them challenging to manage. Many cognitive, affective, behavioral, and perceptual symptoms span multiple neurologic diagnoses—and there is prominent variability in neuropsychiatric symptom burden for a given condition. There is also a relative lack of robust controlled clinical trial evidence and expert consensus recommendations for a range of neuropsychiatric symptom presentations. Thus, the categorical approach (e.g., a discrete diagnosis equals a specific set of medication interventions) used in many other medical conditions can sometimes have limited utility in commonly encountered neuropsychiatric clinical scenarios. In this review, we explore medication management for a range of neuropsychiatric symptoms using a dimensional transdiagnostic approach applied to the neurological patient. This approach allows the clinician to think beyond the boundaries of a discrete diagnosis and treat specific symptom domains (e.g., apathy, impulsivity). Pharmacologic considerations, including mechanisms of action and their application to various neurotransmitter systems and brain networks, are discussed, as well as general recommendations to optimize medication adherence and rapport with the patient. The dimensional, transdiagnostic approach to pharmacological management of patients with neurological conditions will help the clinician treat neuropsychiatric symptoms safely, effectively, and confidently.
Testing general relativity principles at the quantum level
Authors: Piccone Ashley
Published: February 2022

Atom interferometers probe the universality of free fall at small scales
Synthesis and luminescent properties of heteroleptic lanthanide complexes with oxybenzo[
Authors: Balashova Tatyana V. , Polyakova Svetlana K. , Ilichev Vasily A. , Kukinov Andrey A. , Rumyantcev Roman V. , Fukin Georgy K. , Yablonskiy Artem N. , Bochkarev Mikhail N.
Published: February 2022

The heteroligand complexes CpLn(BQ)2(DME) (BQ = 10-oxybenzo[h]quinoline, Cp = cyclopentadienyl, Ln = La (1), Nd (2), Sm (3), Gd (4)) were synthesised by the reaction of Cp3Ln with (BQ)H. The complexes of La, Nd and Sm were structurally characterised. In the case of ytterbium the reaction affords Cp2Yb(BQ)(DME) (5) and homoligand binuclear complex Yb2(BQ)6 (6) iregardless of the molar ratio of initial reagents. Upon UV excitation all the complexes gave rise to fluorescence of ligands in the visible region. The photoluminescent spectrum of compound 1 also contains a phosphorescent band with a lifetime longer than 10 ms. The complexes of Nd, Sm and Yb along with ligand emission display metal-centered luminescent f–f transitions.
Intertwined spin, charge, and pair correlations in the two-dimensional Hubbard model in the thermodynamic limit
Authors: Mai Peizhi , Karakuzu Seher , Balduzzi Giovanni , Johnston Steven , Maier Thomas A.
Published: February 2022

Significance

The high-temperature superconducting cuprates are governed by intertwined striped magnetic and charge orders, in addition to superconductivity. Remarkably similar behavior has also been seen in numerical calculations for the Hubbard model describing the copper–oxygen layers in these materials. Finite-cluster methods typically find that spin- and charge-stripe order dominates, while embedded quantum-cluster methods, which access the thermodynamic limit, often conclude that superconductivity does. Here, we report the observation of fluctuating spin and charge stripes in an embedded cluster calculation for the Hubbard model. This discovery demonstrates that striped states survive in the thermodynamic limit and allows us to study their influence on the model’s superconducting properties, where we find evidence for pair-density-wave correlations intertwined with the stripe correlations.
A perfect X-ray beam splitter and its applications to time-domain interferometry and quantum optics exploiting free-electron lasers
Authors: Reiche Sven , Knopp Gregor , Pedrini Bill , Prat Eduard , Aeppli Gabriel , Gerber Simon
Published: February 2022

Significance

Brilliant, ultrashort, and coherent X-ray free-electron laser (FEL) pulses allow investigations of dynamics at the inherent time and length scale of atoms. However, missing are sequences of phase-locked X-ray pulses, desirable for time-domain correlation spectroscopies and coherent quantum control. Based on selective electron-bunch degradation in the accelerator, combined with two-stage, self-seeded photon emission, we propose an FEL mode, generating subfemtosecond, phase-locked X-ray pulse pairs with up to 100 fs delay. Splitting the electron bunch in the accelerator, instead of photon pulses in the beamline, avoids relative phase jitter. This enables time-domain interferometry, such as the X-ray analog of the ubiquitous Fourier transform infrared spectrometer, and, more generally, all of nonlinear and quantum optics requiring coherent copies of beams.
Microstructure and mechanical characterisation of ZrO2 reinforced Ti6Al4V metal matrix composites by powder metallurgy method
Authors: Haja Syeddu Masooth P , Bharathiraja G , Jayakumar V , Palani Kumaran
Published: February 2022

This study investigated the mechanical and microstructural properties of ZrO2 reinforced titanium metal matrix composites (TMMCs) fabricated using powder metallurgy. The base matrix of the Ti6Al4V alloy was reinforced with ZrO2 at mixing proportions of different wt percentage points at 0, 3, 4, 5 and 6. Microstructure evaluation was carried out to study the bonding characteristics of the matrix and reinforcement, and it was confirmed that the reinforcement was homogenously mixed with the base matrix. The objective is to study the effect of zirconia on mechanical properties such as hardness, compression strength and thermal expansion coefficiency of Ti6Al4V alloy. The hardness, compression strength, and shrinkage rate are increased with the increase of ZrO2. Finally, it was observed that, 6 wt percentage of ZrO2 reinforced composite showed better characteristics in that the hardness and compression strength were the highest among all the proportions used and the coefficient of thermal expansion was low. Due to these promising results, the fabricated ZrO2 reinforced Ti6Al4V composite can be a potential material for structural, aerospace and automotive applications.
Characterization of an advanced cone beam CT (CBCT) reconstruction algorithm used for dose calculation on Varian Halcyon linear accelerators
Authors: Hu Yunfei , Arnesen Marius , Aland Trent
Published: February 2022

In this study, the performance of a new iterative reconstruction algorithm, the pre-clinical AcurosXB iCBCT algorithm, has been characterized on Varian Halcyon linear accelerators with respect to the potential of radiotherapy dose calculations on CBCT images. The study utilized various phantom setups to verify the accuracy of the pre-clinical algorithm under different scatter conditions and compared dose calculations performed on CBCT images reconstructed with the pre-clinical algorithm to those performed on typical planning CT images. The results indicated that despite showing improvements compared to the existing iCBCT protocol, certain restrictions should be introduced when the pre-clinical AcurosXB iCBCT algorithm was used for dose calculations. Changes in the scatter condition exhibited a larger effect on CBCTs than on planning CTs. Therefore, users should be careful in offsetting the patient and positioning the patient’s arms if the resultant images will be used for dose calculations. In addition, protocols with different kV settings should be approached with caution, where 100 kV protocols should only be used to scan the head and neck area, while the rest of the body should be scanned with the 125 kV and 140 kV protocols. When the patient is set up properly and the appropriate energy is selected for the anatomical area, the uncertainty of using the novel AcurosXB iCBCT algorithm for treatment planning dose calculation is within ±2.0%.
Properties of solutions to Pell’s equation over the polynomial ring
Authors: Kalaydzhieva Nikoleta
Published: February 2022

In the classical theory, a famous by-product of the continued fraction expansion of quadratic irrational numbers

D

\sqrt {D}

is the solution to Pell’s equation for

D
D

. It is well-known that, once an integer solution to Pell’s equation exists, we can use it to generate all other solutions

(

u
n

,

v
n

)

n
∈

Z

(u_n,v_n)_{n\in \mathbb {Z}}

. Our object of interest is the polynomial version of Pell’s equation, where the integers are replaced by polynomials with complex coefficients. We then investigate the factors of

v
n

(
t
)

v_n(t)

. In particular, we show that over the complex polynomials, there are only finitely many values of n for which

v
n

(
t
)

v_n(t)

has a repeated root. Restricting our analysis to

Q

[
t
]

\mathbb {Q}[t]

, we give an upper bound on the number of “new” factors of

v
n

(
t
)

v_n(t)

of degree at most

N
N

. Furthermore, we show that all “new” linear rational factors of

v
n

(
t
)

v_n(t)

can be found when

n
≤
3

n \leq 3

, and all “new” quadratic rational factors when

n
≤
6

n \leq 6

.
A generalization of Renault’s theorem for Cartan subalgebras
Authors: Raad Ali
Published: February 2022

We prove a generalized version of Renault’s theorem for Cartan subalgebras. We show that the original assumptions of second countability and separability are not needed. This weakens the assumption of topological principality of the underlying groupoid to effectiveness.
Genetically engineered mesenchymal stromal cells as a new trend for treatment of severe acute graft-versus-host disease
Authors: Keshavarz Shahbaz Sanaz , Mansourabadi Amir Hossein , Jafari Davood
Published: February 2022

Mesenchymal stem cells (MSCs) are a population of non-hematopoietic and self-renewing cells characterized by the potential to differentiate into different cell subtypes. MSCs have interesting features which have attracted a lot of attention in various clinical investigations. Some basic features of MSCs are including the weak immunogenicity (absence of MHC-II and costimulatory ligands accompanied by the low expression of MHC-I) and the potential of plasticity and multi-organ homing via expressing related surface molecules. MSCs by immunomodulatory effects could also ameliorate several immune-pathological conditions like graft-versus-host diseases (GVHD). The efficacy and potency of MSCs are the main objections of MSCs therapeutic applications. It suggested that improving the MSC immunosuppressive characteristic via genetic engineering to produce therapeutic molecules consider as one of the best options for this purpose. In this review, we explain the functions, immunologic properties, and clinical applications of MSCs to discuss the beneficial application of genetically modified MSCs in GVHD.
Explicit and automatic ejection fraction assessment on 2D cardiac ultrasound
Authors: Moal O , Roger E , Lamouroux A , Vuillet C , Bonnet G , Moal B , Lafitte S
Published: February 2022

Funding Acknowledgements

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

Background

Left ventricular ejection fraction (EF) is a key parameter to assess cardiovascular functions in 2D cardiac ultrasound, but its manual assessment is time-consuming and subject to high inter and intra-observer variability.

Deep learning-based approaches have been proposed to automatically predict EF but can suffer from a lack of explainability and interpretability, which limit the trust of the clinician and prevent errors from being detected.

Purpose

In this context, we propose a fully automatic method to reliably evaluate the biplane left ventricular EF on 2D echocardiography while following the modified Simpson’s rule calculation steps to provide explicit details to clinicians.

Methods

A deep learning model based on U-Net architecture was trained on internal apical 4 and 2-chamber echocardiographic images to segment the left ventricle and locate the mitral valve. Predicted segmentations are then validated with a statistical shape model which detects potential failures that could impact the final EF evaluation. Finally, end-diastolic and end-systolic frames are identified thanks to a spline interpolated from the remaining LV segmentations’ areas, and the EF is estimated on all available cardiac cycles.

This approach was trained on a dataset of 783 patients. Its performances were evaluated on an internal dataset of 200 patients with a large diversity of EF and on an external openly available dataset containing 450 patients.

Results

On the internal dataset, EF assessment achieved a mean absolute error of 6.10% and a bias of 1.56 ± 7.58% using multiple cardiac cycles and removing failed segmentations. Regarding end-diastolic and end-systolic volumes, the mean absolute error was evaluated at 13.75mL and 10.70mL respectively. Segmentation performances were evaluated with the Dice and the Hausdorff distance, respectively at 0.92 ± 0.41 and 6.13 ± 2.9mm.

On the external dataset, the approach predicted EF with a mean absolute error of 5.39% and a bias of -0.74 ± 7.12%. The mean absolute error for end-diastolic volume was 15.40mL and for end-systolic volume 8.18mL.

Conclusions

Following the recommended guidelines, we proposed an end-to-end fully automatic approach achieving state-of-the-art performances in EF evaluation in 2D cardiac ultrasound while giving explicit details to the clinicians at each step of the assessment. Abstract Figure. End-to-end fully automatic approach
Changes in left atrial mechanics following surgical myectomy: the key component of clinical improvement
Authors: Badran H , Soliman MA , Faheem N , Fouad R , Yacoub MY
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Objectives

The impairment of left atrial mechanics(LA) is previously described in hypertrophic cardiomyopathy (HCM). It is independently influenced by left ventricular(LV) mechanics and correlated to the severity of LV phenotype. We examined the alterations in LA structure and mechanics following surgical septal myectomy using vector velocity imaging.

Methods

Twenty-five HCM patients, 60% males with mean age (34.5 ± 12 years) were investigated before and six months after surgical myectomy using VVI. In addition to LA size and volume index (LAD, LAVI), LA reservoir function using peak systolic strain(εsys) & systolic strain rate(SRsys), and LA conduit(SRe) and LA contractile(SRa) functions were analyzed. Electrophysiologic properties of the LA were investigated using the difference between longest and shortest cycle; time to peak SRa(TTP-d) and the standard deviation(SD) of TTP-mean derived from regional SRa curves. Similar longitudinal εsys parameters were quantified in LV and right ventricle (RV) from apical views. The magnitude of changes in LA function (Δ) was expressed as the difference between pre and post myectomy values.

Results

Post myectomy, the studied cohort demonstrated atrial reverse remodeling and 68% of patients showed normalization of LAVI (<34ml/m2). All patients demonstrated a reduction of: LVOT gradient to < 20 mmHg, septal thickness, LV mass index, severity of mitral regurgitation and improvement of functional class from NYHA class III to class I. Following myectomy, although there was significant reduction of LV and RV systolic mechanics, there was a considerable increase in LA reservoir function (εsys:26 ± 13 vs 31 ± 16%, P<.03, SRsys:0.9 ± 0.4 vs 1.2 ± 0.5% s-1, P < 0.02) and contractile function (SRa: -0.8 ± 0.4 vs -1.2 ± 0.9 s-1, P < 0.04) respectively. LA Δ εsys was inversely correlated to pre-myectomy maximal wall thickness (r=-.494, P<.003) & LAVI (r=-.489, P<.01) and directly correlated to pre-myectomy LA εsys % (r=.639, P<.001) and LA SRa (r=.536, P<.008). Δ SRe showed direct correlation to LV εsys (r=.405, P< .04) and LA SRe (r=.635, P<.001) before surgery, respectively. ΔSRa was directly correlated to LA εsys % before surgery (r=.701, P<.0001). ΔTTP-SD and ΔTTP-d, showed inverse correlation to LV systolic mechanics before surgery (r=-.418, P<.038 and r=-.395, P<.050) respectively. Stepwise linear regression analysis identified global LV εsys% and RV εsys pre-myectomy as independent determinants of normalization of LAVI following myectomy, (β: 0.6, 95% CI: -4.22 - -1.96, p< 0.001) (β: 0.4, 95% CI: -4.06 - -0.57, p < 0.04) respectively.

Conclusion

Surgical myectomy is associated with improvement of LA mechanical properties and reverse remolding in HCM patient with symptomatic improvement despite subclinical reduction of LV and RV systolic mechanics.
Left ventricular global longitudinal strain as an early marker of the need for echocardiographic follow-up in patients with breast cancer: a real-life study
Authors: Gallo Fernandez I , Esteban Martinez F , Delgado Ortega M , Rodriguez Almodovar A , Martin Ruiz M , Pastor Wulf D , Lopez Baizan J , Carnero Montoro L , Gonzalez Manzanares R , Pericet Rodriguez C , Fernandez Ruiz A , Rodriguez Nieto J , Piserra Lopez-Fernandez De Heredia A , Pan Alvarez-Ossorio M , Mesa Rubio D
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Introduction

The monitoring of the left ventricular ejection fraction (LVEF) is a common practice in patients with breast cancer undergoing chemotherapeutic treatment. Although indiscriminate follow-up is not very cost-effective, we don’t have enough data to determine which patients would benefit from it.

Purpose

To analyze if any baseline ventricular function echocardiographic parameter can help to identify the subsequent development of ventricular dysfunction secondary to cardiotoxic drugs (DV-CTOX).

Methods

Retrospective study of patients with breast cancer who have received treatment with anthracyclines with / without adjuvant treatment with immunotherapy and / or radiotherapy. We analyzed baseline and follow-up ventricular function parameters (LVEF estimated by 2D-3D automatic quantification and semi-automatic quantification of global longitudinal strain (GLS)).

Results

We included 93 patients (mean age 59 ± 11 years, 98.9% women). 67% received immunotherapy and 84% radiotherapy. Median follow-up was 6 months. 10 patients (11%) developed DV-CTOX. There were differences in baseline clinical characteristics between patients and those with no DV-CTOX. Regarding echocardiographic parameters we didn’t observe differences between both groups in basline 2D LVEF (65 ± 1% vs 62 ± 14%, p = 0.4), and 3D LVEF (60 ± 7% vs 57 ± 8%, p = 0.4), although the GLS was lower in patients who later developed DV CTOX (GLS 19 ± 3% vs 16 ± 3%, p = 0.03); At follow-up, patients who developed DV-CTOX had worse LVEF estimated by 2D-3D and maintained a worse GLS value (52 ± 7% vs 69 ± 8% p <0.001.49 ± 8% vs 61 ± 4%, p = 0.005 and 14 ± 3% vs 20 ± 4%, p = 0.04 respectively). We used the area under the curve for the use of baseline GLS as a diagnostic method for the early detection of DV-CTOX. It was 0.785 (CI 0.585-0.985 for a p value = 0.047). A baseline GLS cut-off point of 17.5% was determined with a sensitivity of 73% and a specificity of 80%.

Conclusion

The quantification of baseline GLS in patients with breast cancer who are going to start treatment with cardiotoxic drugs could help to discriminate which patients require a closer LVEF monitoring, improving efficiency in the Cardio-Onco-Hematology unit. A value greater than 17.5% in absolute terms of baseline GLS could be an optimal cut-off point that discriminates between patients who will develop DV-CTOX. Abstract Figure.  Abstract Figure.
Hidden systolic dysfunction of the right ventricle in patients with increased pulmonary vascular resistance 3 months after COVID-19 pneumonia
Authors: Shirokov N , Yaroslavskaya E , Krinochkin D , Osokina N
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

Coronavirus disease 2019 (COVID-19) is caused by the novel severe acute respiratory syndrome coronavirus 2. Pulmonary vascular resistance (PVR) is an important hemodynamic variable used in the management of patients with cardiovascular and pulmonary pathology. Doppler echocardiography has significantly impacted clinical medicine by its ability to assess intracardiac hemodynamics noninvasively. It seems actual to reveal the relationship between right heart function and lungs involvement in COVID-19.

Purpose

To assess the relationship right ventricular (RV) echocardiographic structural and functional parameters with indicators of increased pulmonary vascular resistance (PVR) in patients 3 months after COVID-19 pneumonia.

Methods

96 patients (mean age 47.6 ± 15.2 years) were examined during hospitalization and at control visit (3 months follow-up). The equation tricuspid regurgitation velocity / time-velocity integral of the RV outflow tract X 10 + 0.16 has been used to determine PVR. Patients were divided into 2 groups: I group (n = 31) – patients with increase of PVR ≥1.5 Wood unit (WU) and II group (n = 65) – with decrease of PVR <1.5 WU.

Results

At baseline groups did not differ in main clinical characteristics, including severity of lung involvement in COVID-19 by computed tomography (32.7 ± 22.1% vs 36.5 ± 20.4%, р=0.418). Linear, planimetric and volumetric parameters did not differ significantly between groups. At the control visit RV free wall (FW) global endocardial longitudinal strain (LS) (-19.3 [-17.9; -25.8] % in group I vs -23.4 [-19.8; -27.8] % in group II, p = 0.048), tricuspid annular plane systolic excursion (21.7 ± 3.8 mm vs 23.3 ± 3.4 mm, p = 0.040) and RV maximum systolic velocity assessed by tissue Doppler imaging (12.3 ± 2.4 cm/s vs 13.4 ± 2.0 cm/s, p = 0.024) were significantly reduced in group I, systolic pulmonary artery pressure (sPAP) according to Otto C. (32.0 [26,0; 35.0] mm Hg vs 23.0 [20.0; 28.0] mm Hg, p <0.001) was significantly increased in group I. According to logistic regression only endocardial RV FW LS (OR 0.859; 95% CI 0.746 - 0.989; p = 0.034) and sPAP (OR 1.248; 95% CI 1.108 - 1405; p <0.001) had an independent relationship with increase of PVR. According to Spearman correlation analysis the moderate relationship was found between PVR and mean pulmonary artery pressure according to Mahan G. (r = 0.516, p = 0.003), PVR and RV–pulmonary artery coupling (r=-0.509, p = 0.007) in group I at the control visit.

Conclusion

Hidden RV systolic dysfunction defined as decreased endocardial RV FW LS to -19.3% is associated with increased PVR ≥1.5 WU in patients 3 months after COVID-19 pneumonia. Abstract Figure. RV FW LS by STE
Multimodal imaging assessment of left atrial strain in cardiac amyloidosis and hypertrophic cardiomyopathies
Authors: Lucas C , Martel H , Ruimy A , Fabre C , Gardenat A , Rique A , Michel N , Dernys A , Jacquier A , Habib G
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

Despite the increasing number of studies concerning Left Atrial Strain (LAS), few data are available comparing LAS patients with cardiac amyloidosis (CA) and sarcomeric hypertrophic cardiomyopathies (HCM).

Purposes

We aimed to perform a comparative multimodal imaging analysis of LAS of a prospective cohort of patients with CA and HCM.

Methods

For each enrolled patient, we performed same-day two and three-dimension echocardiography (TTE) and cardiac magnetic resonance imaging (CMR) to blindly measure the peak atrial longitudinal strain (PALS) and the peak atrial contraction strain (PACS). Patients with acute atrial fibrillation were excluded.

Results

  Between January 2020 and July 2021, 67 patients were included: 31 patients with CA (age 75.1 ± 10 years, left ventricular ejection fraction 60.6 ± 10.4%, maximum left ventricular thickness 17.8 ± 3.9 mm) and 36 with HCM (age 50.8 ± 15.5 years, left ventricular ejection fraction 66.1 ± 9.8%, maximum left ventricular thickness 20.7 ± 4.5 mm). Left atrial volume was similar in the 2 groups (42.5 ± 15.6 mL/m2 in HCM vs 47.9 ± 15 in CA, P = 0.1557).

Concerning PALS, its values for CA and for CMH were on 2D TTE manual (10.9 ± 5.8% vs 21.4 ± 9.4%, P < 0.001), 2D TTE automatic (11.5 ± 7.3% vs 22.9 ± 10.2%, P < 0.001), 3D TTE (10 ± 6.8% vs 18.1 ± 6.7%, P < 0.001), and CMR (11.3 ± 8 vs 24.4 ± 17.1, P < 0.001) respectively.

Concerning PACS, its values for CA and for CMH were on 2D TTE manual (5.2 ± 3.4% vs 10 ± 4%, P < 0.001), 2D TTE automatic (4.9 ± 3.9% vs 10.2 ± 5.1%, P < 0.001), 3D TTE (3.6 ± 3.8% vs 7.9 ± 4%, P = 0.001) and CMR (6.2 ± 5.8% vs 11.9 ± 9%, P = 0.004) respectively.

Multivariate analysis adjusted on main factors influencing LAS (left ventricular (LV) mass, LV ejection fraction, LV global longitudinal strain, renal function and history of hypertension) found that the differences between the two groups remained significant for PALS and PACS for almost all technics.

Furthermore, although concordance between the 3 echocardiographic technics was excellent (the interclass correlation coefficient (ICC) was higher than 0.80 between each TTE methods), ICC was poor between TTE and CMR technics: 0.40 (0.18-0.59) for manual 2D TTE and CMR, 0.46 (0.24-0.63) for auto 2D TTE and CMR, 0.40 (0.14-0.60) for 3D TTE and CMR.

Conclusion

Our study is the first to describe and compare, both on TTE and CMR, LAS on a prospective cohort of patients with CA and HCM. Although they have same mean left atrial volume, we found significant differences on PALS and PACS between these two groups of patients on all the studied technics. These findings may be used in future multi-modality imaging studies dealing with diagnosis or prognosis of these hypertrophic cardiopathies. Abstract Figure. LAS 2D TTE manual  Abstract Figure. LAS comparison between CA and HCM
Strain measurement for 2D echo with ultrasound enhancing agents can be performed with software available for non-enhanced recordings
Authors: Church M , Foster B , Choy J , Pituskin E , Paterson DI , Becher H
Published: February 2022

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): ABACUS Cardiovascular Research Centre, Mazankowski Alberta Heart Institute

Background

Global longitudinal strain (GLS) measurement are less reliable when 2D image quality is reduced. While ultrasound enhancing agents (UEA; also known as "echo contrast") have been shown to enhance the reliability of EF measurements, there has been sparse evidence on performing GLS measurements after UEA injection. The aim of this study was to assess the feasibility of GLS analysis using the same software validated for non-enhanced 2D recordings.

Methods

GLS measurements were performed before and after injection of an approved UEA in 131 patients with acceptable image quality for GLS measurements. These patients were referred prior to chemotherapy initiation or were being monitored for potential cardiotoxic effects. As all these patients undergo echocardiography with UEA in order to achieve the best reproducibility of EF measurements, comparison of GLS measurements with and without UEA was possible. A commercially available ultrasound system was used and the same analysis software was applied. On end-diastolic and end-systolic frames, the inner border of the region of interest was manually adjusted to align with interface between the compact and trabeculated myocardium on non-enhanced images and the LV blood pool on the recordings with UEA.

Results

GLS measurements on recordings with UEA were performed in 131 patients. A strong positive correlation (r 0.67, p < 0.001) was found between measurements on non-enhanced recordings with mean bias 0.58% (see figure). Mean GLS was 19.5 +/- 2.1% from non-enhanced recordings and 20.1 +/- 2.2% from UEA recordings. Differences in GLS > 2% between methods were related to foreshortening or suboptimal delineation of segments on non-contrast recordings.

Conclusion

On a commercially available echocardiography scanner, software developed for GLS measurements on non-enhanced 2D recordings can be also applied to recordings that use UEA. Comparable results are obtained, provided the LV cavity is well delineated and not foreshortened. Abstract Figure 1
Early improvement of cardiac performance after atrial fibrillation direct current cardioversion
Authors: Colombo C , Degiovanni A , Ghiglieno C , Maulini GM , Patti G
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) is the most common arrhythmia and one of the most prevalent cardiac disease. Restoring sinus rhythm improves long-term systolic and diastolic function, quality of life and relieve symptoms in patients with symptomatic AF.

Purpose

The aim of the study was to evaluate the early effects of AF direct current cardioversion on myocardial deformation using speckle-tracking echocardiography.

Methods

51 patients with persistent AF who underwent successful direct current cardioversion were enrolled (age: 70 ± 9 years; men: 72.5%). Patients with ischemic, dilatative, hypertrophic cardiomyopaties, valvular heart disease, previous cardiac interventions were excluded from the study. Left ventricular ejection fraction was 55.2 ± 7.0%. A transthoracic echocardiography was performed one day before the successful cardioversion and 6 hours after, employing 2d standard echocardiography and speckle-tracking technique to evaluate left atrial, left ventricular and free-wall right ventricular longitudinal strain.

Results

Restoration of sinus rhythm led to a reduction of the heart rate (83 ± 14 vs 70 ± 13 bpm, p < 0.001). After about six hours from successful AF direct current cardioversion, we highlighted an increase in left ventricular filling pressure estimated with the ratio E/E’ (8.19 ± 0.29 vs 9.34 ± 0.41, p = 0.0016). A significant increase in left atrial longitudinal strain (10.47 ± 0.64% vs 19.76 ± 1.01%, p < 0.001, Figure A) and in left ventricular longitudinal strain (-13.10 ± 0.60% vs -15.86 ± 0.51%, p < 0.001, Figure C) were noticed; also the free wall right ventricular longitudinal strain increased (-12.06 ± 1.16% vs -15.86 ± 1.29%, p = 0.047, Figure B).

Conclusion

Restoring sinus rhythm improves cardiac performance as evidenced by the increase in either left atrial and bi-ventricular longitudinal strain, suggesting an amelioration even if after early time. Abstract Figure
Using parameters of myocardial deformation as markers of pathological postinfarction remodeling
Authors: Oleinikov V , Golubeva A , Galimskaya V , Babina A , Burko N
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Objective

to predict pathological left ventricular (LV) remodeling using global parameters of strain and twisting.

Methods

the study included 114 people with primary ST-segment elevation myocardial infarction (STEMI): 14 women and 100 males aged 32 to 67 years (52.3 ± 8.4). STEMI has been confirmed by ECG data, cardiospecific biomarkers (troponin T, CPK-MB) and coronary angiography - the presence of one infarct-related coronary artery in the absence of hemodynamically significant stenosis of other arteries. Echocardiography has been performed using a MyLab ultrasound scanner (Italy) on the 7th-9th day, 3rd, 6th and 12th months after the disease onset with the evaluation of standard parameters. On the 7th-9th days the parameters of global longitudinal (GLS,%), circumferential (GCS,%) strain, and LV twisting (Twist, °) have been analyzed using the X-Strain ™ software. The criterion for pathological LV remodeling has been considered to be an increase in EDVi ≥ 20% compared with the initial value. Prediction of pathological remodeling has been performed using ROC analysis by 3 criteria. To assess the quality of the model, the area under the curve (AUR –Area under ROC) has been determined with the calculation of 95% confidence intervals and the statistical significance of the point estimate of the area.

Results

Within 48 weeks pathological remodeling was developed in 45 (39.5%) patients. Three months after the index event, LV remodeling was detected in 24 (53.3%) patients of these 45; after 6 months - in another 15 (33.3%); after 12 months - in another 6 (13.4%). GLS - 11.7% with 96% sensitivity and 80% specificity, AUR 0.750 (95% CI 0.659 - 0.841), GCS - 12.4% with test sensitivity and specificity - 90% and 82%, respectively ((AUR 0.641 ( 95% CI 0.534 - 0.749)), Twist - 7.8 ° with a sensitivity of 93% and a specificity of 78%, AUR 0.657 (95% CI 0.558 - 0.757) predict the development of pathological postinfarction LV remodeling on the 7th-9th day. For all models the value of p ≤ 0.001.

Conclusion

Previously, LV remodeling has developed within 3 months after STEMI in 45 (39.5%) patients. The longitudinal strain, measured in the acute period of STEMI, has the greatest predictive ability in relation to the development of pathological postinfarction LV remodeling.
Correlation relationships of myocardial work indices with left ventricular ejection fraction and postsystolic strain index in healthy individuals
Authors: Babina A , Galimskaya V , Golubeva A , Korenkova K , Burko N , Oleinikov V
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Purpose

to identify correlations between the indicators of the global work of the left ventricular (LV) myocardium with the ejection fraction (EF) and the post-systolic contraction index (iPSI) in healthy individuals.

Methods

the study included 70 healthy people: 34 men and 36 women aged 21 to 61 years (mean age 39.3 ± 8.9 years). Inclusion criteria: absence of complaints, anamnestic and physical data indicating the presence of cardiovascular diseases and / or damage to other organs and systems; ECG without significant changes; lack of regular intake of any medications. Exclusion criteria: diseases of the cardiovascular system, respiratory system, kidney, liver; type 1 and 2 diabetes mellitus; chest trauma; BMI> 30 kg / m2; poor visualization of the echogram. Echocardiography was performed on a Vivid GE 95 Healthcare scanner (USA). EchoPAC software version 202 (GE Healthcare) has been used. LVEF has been determined by the Simpson biplane method. The index of global myocardial work (GWI, mmHg%), global constructive work (GCW, mmHg%), global wasted work (GWW, mmHg%), global work efficiency have been assessed in automatic mode. (GWE,%). The iPSS and the number of segments, the PSS index of which was more than 1, have been automatically determined. Spearman"s correlation coefficient (r) has been used to study the relationship between quantitative traits.

Results

indicators of global myocardial work had the following values: GWE - 97.5 (97; 98)%; GWI - 2062.6 ± 345.5 mm Hg%; GCW - 2353.3 ± 344.6 mm Hg%; GWW - 45 (32; 68) mm Hg%. LVEF on average 60.8 ± 4.6%, iPSS - 1.35 (0.73; 2.35). The average number of segments with iPSS> 1 - 4 (3; 6) (26.5%). The correlation coefficient of LVEF with GCW was 0.49 (p = 0.00001), with GWI - 0.45 (p = 0.00007), with GWE - 0.25 (p = 0.032), with GWW - (-0 , 19) (p = 0.1). Correlation coefficient of iPSS with indicators of myocardial work: with GWE - (-0.85) (p = 0.0007), with GWW - 0.85 (p = 0.00004), with GCW - (-0.05) (p = 0.68), with GWI - 0.07 (p = 0.5). When determining the relationship between the number of segments with iPSS> 1 and GWE, the correlation coefficient was 0.46 (p = 0.0002), with GWW - 0.57 (p = 0.0003), with GWI - 0.26 (p = 0 , 03), with GCW - 0.12 (p = 0.3).

Conclusions

GCW and GWI had moderate positive correlations with LVEF. GWE and GWW had a strong relationship with iPSS and moderate correlations with the number of segments with iPSS> 1.
Total atrial conduction time and its relationship with morphological & functional characteristics in hypertrophic cardiomyopathy
Authors: Pagourelias E , Boulmpou A , Alexandridis G , Tsarouchas A , Mouselimis D , Bakogiannis K , Karamanolis A , Vergopoulos S , Tsavousoglou C , Antoniadis A , Fragakis N , Papadopoulos CE , Vassilikos V
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

Total atrial conduction time (TACT), estimated by tissue Doppler imaging (TDI), is an index reflecting left atrial (LA) structural and electrical remodeling, connected to atrial fibrillation (AF) development and heart failure progression in various substrates. In hypertrophic cardiomyopathy (HCM), the significance of TACT beyond AF and its determinants are not fully investigated.

Purpose

Aim of this study was to estimate TACT in a cohort of HCM patients without AF history and to examine its relationship with other parameters of atrial myopathy, such as LA volume index (LAVI) or LA reservoir strain (LARS). Additionally, to investigate TACT correlation with other phenotypic and functional characteristics of HCM.

Methods

 We included 50 HCM patients (60 ± 16 years, 80% male, maximum wall thickness 18.6 ± 4.1mm) without history of AF who have consecutively undergone 2D-speckle tracking echocardiography and cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). TACT was measured from the onset P wave on electrocardiogram to the peak A’ wave of the lateral LA wall using TDI (left panel). Burden of fibrosis (percentage of LV mass) was defined by LGE extent (>5 standard deviations compared to nulled myocardium) in CMR slices. Cut-off points for TACT, LAVI and LARS were adopted by literature (≥115 msec, ≥34 mL/m2 and <21.3 % respectively).

Results

 All HCM patients had preserved EF (61.8 ± 8%), while 13 (26%) presented outflow tract obstruction and 4 (8%) diastolic dysfunction stage≥2. LGE was observed in 32 patients (64%) occupying 7.2 ± 5% of left ventricular (LV) mass. Mean TACT was 139.9 ± 22 msec, with LAVI being 30.8 ± 16.1 mL/m2 and LARS 27.6 ± 13.9%. After assessing prevalence of atrial myopathy parameters, 41 patients (82%) presented a prolonged (≥115 msec) TACT with only 13 of them having also a significantly dilated LA (≥34 mL/m2) and 16 an impaired LARS. Among HCM demographic, phenotypic and functional characteristics tested, age and LV mass index were found to be the only independent regressors of TACT (r = 0.54, p < 0.0005 and r = 0.44, p = 0.002 respectively, right panels). On the contrary, no significant correlation was established between TACT and traditional diastolic dysfunction indices such as E/E’ or fibrosis extent.

Conclusions

Atrial electro-mechanical delay assessed through TDI based TACT, is very frequent among HCM patients irrespective of AF and even before LA dilatation and LA strain impairment.  Age and hypertrophy magnitude are the main determinants of TACT, the prognostic significance of which remains to be further elucidated. Abstract Figure.
Prognostic significance of peak atrial longitudinal strain in patients with functional mitral regurgitation
Authors: Gomes D , Lopes P , Freitas P , Albuquerque F , Horta E , Reis C , Guerreiro S , Abecassis J , Trabulo M , Ferreira A , Ferreira J , Ribeiras R , Mendes M , Andrade MJ
Published: February 2022

Funding Acknowledgements

Type of funding sources: None.

Background

Chronic mitral regurgitation has been shown to promote left atrial (LA) dysfunction and remodeling. However, the significance of LA dysfunction in this setting has not been fully investigated. The aim of our study was to assess the prognostic impact of peak atrial longitudinal strain (PALS), a surrogate of LA function, in a cohort of patients with LV systolic dysfunction and functional mitral regurgitation (FMR).

Methods

Patients with at least mild FMR and reduced LVEF (< 50%) under optimized medical therapy who underwent transthoracic echocardiography between 2010 and 2018 were retrospectively identified at a single-centre. FMR grading was undertaken according to the new 2021 valvular guidelines. PALS was assessed by 2D speckle tracking in apical 4-chamber view (as per EACVI current recommendations). Cox proportional hazards regression was applied for univariable and multivariable analysis to investigate the association between clinical and echocardiographic parameters, namely PALS, and all-cause mortality.

Results

A total of 307 patients (median age 70 years, 77% male) were included. Median LVEF was 35% (IQR: 27 – 40%) and median mitral regurgitant volume was 25mL (IQR: 14 – 34mL). According to the new ESC 2021 valvular guidelines, 32 patients had severe FMR (10%). During a median follow-up of 3.5 years (IQR 1.4 – 6.6), 148 patients died. Median PALS was 14% (IQR 8 – 20%). The unadjusted mortality incidence per 100 persons-years increased with progressively lower values of PALS (figure 1). On ROC curve analysis, the best PALS cut-off value associated with mortality was < 15%. Kaplan-Meier survival curves according to FMR severity and PALS > or < 15% are depicted in figure 2. PALS remained independently associated with all-cause mortality on multivariable analysis (adjusted hazard ratio [aHR]: 0.94; 95%CI: 0.90 – 0.98; p = 0.004) even after adjustment for several (n = 14) clinical and echocardiographic confounders.

Conclusion

In a cohort of patients with reduced LVEF and functional mitral regurgitation, peak atrial longitudinal strain was associated with all-cause mortality. Abstract Figure 1  Abstract Figure 2