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Tricuspid valve detachment for ventricular septal defect closure: A meta-analysis of...
Dou Yuan
Li ping Chen

Dou Yuan

and 3 more

August 29, 2022
Background: Ventricular septal defect (VSD) is one of the most common congenital cardiac defects, However, in some cases VSD sites are difficult to expose due to obstruction from chordal attachments and leaflets of the tricuspid valve (TV)[6](#ref-0006). To systematically review the efficacy and safety of tricuspid valve detachment,( TVD) versus conventional surgical repair ( non-TVD) in the treatment of ventricular septal defect ( VSD) .This article is aimed to compare the many outcomes from existing studies and provide evidence regarding the necessity of performing TVD. Methods:We searched the following databases: PubMed via NCBI, the Cochrane Central Register of Controlled Trials (no date restriction),Medline via Ovid (from 1966 to May 2020); Embase via Ovid (no date restriction) and China National Knowledge Infrastructure for studies comparing the efficacy of tricuspid valve detachment (TVD) and other surgical techniques in VSD repair. Cardiopulmonary bypass time, Cross-clamp time; postoperative complications including residual defect ,Postoperative atrioventricular block ,Implantation of pacemakers, tricuspid regurgitation ;Length of stay, Length of ICU stay were analyzed. Results: Only 9 studies were included after selection (Table 1), including 7 retrospective cohort studies, 1 respective cohort study and 1 prospective observational stud,a patient pool of 1404 patients with 374 underwent TVD and 1030 underwent non-TVD procedures,met the inclusion criteria.Meta analysis has drawn to the following conclusions. Firstly, TVD prolongs CPB time (MD=7.75, 95% CI=2.60-12.89, p=0.003) and cross-clamp time(MD=7.77, 95% CI=4.76-10.78, p<0.001) compared with non-TVD techniques in VSD repair surgeries. Secondly, no significant difference exists in LOS, length of ICU stay, postoperative atrioventricular block, implantation of pacemakers, incidence of ≥mild TR postoperatively and at discharge, as well as incidence of ≥small residual VSD after surgery and during follow-up( all P > 0. 05). Thirdly, application of TVD increases the risk of TR during follow-up(OR=2.42, 95% CI=1.55-3.76, p<0.001). Conclusion: VSD closure using TVD technique results in longer CPB and cross-clamp time, and increases risk of TR during follow-up. TVD provides equally viable and safe alternative in treating VSD.
WELL-POSEDNESS FOR CAUCHY FRACTIONAL PROBLEMS INVOLVING DISCRETE CONVOLUTION OPERATOR...
Jorge Gonzalez Camus

Jorge Gonzalez Camus

August 29, 2022
This work is focused on establishing sufficient conditions to guarantee the well-posedness of the following nonlinear fractional semidiscrete model \begin{equation*} \begin{cases} \mathbb D^\beta_t u(n,t)= B u(n,t) + f(n-ct,u(n,t)),\, &n\in\mathbb{Z}, \;t>0,\\ u(n,0)=\varphi(n),\; &n\in\mathbb{Z},\\ \end{cases} \end{equation*} under the assumptions that $\beta \in (0,1]$, $c>0$ some constant, $B$ is a discrete convolution operator with kernel $b\in\ell^1(\Z)$, which is the infinitesimal generator of the Markovian $C_0$-semigroup and suitable nonlinearity $f$. We present results concerning the existence and uniqueness of solution, as well as establishing a comparison principle of solutions according to respective initial values.
A kinetic study of biotransformation from valencene to nootkatone in an oscillatory b...
Mohamed Chilmeran
Matthew Hodges

Mohamed Chilmeran

and 2 more

August 19, 2022
In this paper we report our kinetic study of an oxidation reaction from valencene to nootkatone using enzyme in an oscillatory baffled reactor (OBR). A full kinetic model using the Langmuir-Hinshelwood formalism was established and applied to the experimental data, allowing reactor schemes and orders to be confirmed and reaction rate constants to be extracted. The analysis of reaction rate constants suggests that most of the reversible reaction steps can be treated as irreversible, simplifying reaction schemes. The effect of mixing intensity on the kinetics was also investigated.
5 Alpha Reductase deficiency; an important cause of 46 XY DSD: report of 3 cases with...
Samaneh Norouzi asl
reza ibrahimi

Samaneh Norouzi asl

and 3 more

August 29, 2022
5 α reductase deficiency is a genetic disorder causing 46 XY disorder of sex development (DSD). Typical clinical feature is a male with female external genitalia or undervirilization at birth. Here we report 3 cases of this disorder within a family
Shock wave kinematics in interstellar gas clouds with dust particles
Swati Chauhan
Antim Chauhan

Swati Chauhan

and 2 more

August 29, 2022
In this article, a system of partial differential equations governing the one-dimensional motion of an inviscid gas with solid dust particles is considered. The evolutionary behavior of cylindrical and spherical shock waves in dusty gas is determined. To accomplish this, we used a technique that is based on the kinematics of the one-dimensional motion of shock waves. This allowed us to derive an infinite hierarchy of transport equations that describe the strength of shock waves and the induced discontinuity behind them. These equations are used to determine both the decay and growth behaviors of shock waves in dusty gas. Considering the first two truncation approximations, the results so obtained are compared with the results obtained by Guderley's exact solution and CCW approximation.
Stationary and oscillatory patterns of a food chain model with diffusion and predator...
Renji Han
Gergely Rost

Renji Han

and 1 more

August 29, 2022
In this paper, we investigate pattern dynamics in a reaction-diffusion-chemotaxis food chain model with predator-taxis, which enriches previous studies about diffusive food chain models. By virtue of diffusion semigroup theory, we first show the global classical solvability and uniform boundedness of the considered model over a bounded domain Ω ⊂ R N ( N ≥ 1 ) with smooth boundary. Then the linear stability analysis for the considered model shows that chemotaxis can induce the unique positive spatially homogeneous steady state loses its stability via Turing bifurcation and Turing-spatiotemporal Hopf bifurcation, which results in the formation of two kinds of important spatiotemporal patterns: stationary Turing pattern and oscillatory pattern. Simultaneously, the threshold values for Turing bifurcation and Turing-spatiotemporal Hopf bifurcation are given explicitly. In addition, the existence and stability of non-constant positive steady state that bifurcates from the positive constant steady state is investigated by the abstract bifurcation theory of Crandall-Rabinowitz and eigenvalue perturbation theory. Finally, numerical simulations are performed to verify our theoretical results, and some interesting non-Turing pattern are found in temporal Hopf parameter space by numerical simulation.
Carbohydrate Polymers Template
rui li

rui li

August 29, 2022
Pellentesque tincidunt lobortis orci non venenatis. Cras in justo luctus, pulvinar augue id, suscipit diam. Morbi aliquet fringilla nibh, vel pellentesque dui venenatis eget. Orci varius natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Donec ultricies ultrices magna gravida porta. Maecenas accumsan diam dui, auctor ornare ex pellentesque id. Integer tempus massa id augue finibus convallis. Nulla vestibulum, nisl id tempor pulvinar, felis dui pellentesque lacus, quis bibendum metus enim sed ex.
An approach of measuring velocity based on auto-correlation in a single frame for IEE...
Sudun Zhao
Wei Liu

Sudun Zhao

and 3 more

August 29, 2022
In this letter, we propose a velocity measurement algorithm based on auto-correlation in a single frame for IEEE 802.11ad. The periodicity of the Golay sequences in the preamble is exploited in the algorithm to estimate the time delay and achieve the velocity measurement at the same time. The improved measuring accuracy is obtained as the effection of noise is suppressed by designing and utilizing the auto-correlation function.
Novel Anti-Cancer Therapies and Cardiac Outcomes :Systematic Reviews
shimaa Kotb

shimaa Kotb

August 29, 2022
\cite{Kotb_2022}Shaymarafat.dental@gmail.com:
Transcatheter ventricular septal defect closure via femoral vein alone under transtho...
LiuLiu Huang
Mai Chen

LiuLiu Huang

and 6 more

August 28, 2022
Objective. Transcatheter closure of congenital ventricular septal defects under echocardiography guidance could avoid potential radiation damage from fluoroscopy probes. However, mini-surgical incision, transesophageal echocardiography combined with tracheal intubation, and limited artery access further complicate the procedure. Therefore, we aimed to describe our preliminary experiences in percutaneous VSD closure via the femoral vein only under transthoracic echocardiography (TTE) guidance. Methods. Between December 2018 and November 2021, 19 patients underwent transcatheter VSD closure via femoral vein alone under the guidance of TTE in our hospital. The morphology, location, diameter of VSD, and procedural outcomes were thoroughly reviewed. Symmetric, asymmetric, or eccentric occlusion device was chosen for closure based on the VSD characteristics. Results. There were 16 perimembranous VSD and 3 intracristal VSD patients in this cohort. The range of diameter of the VSD was from 3.8 to 7.4 mm. Fifteen symmetrical occluders were implanted in 13 perimembranous and 2 intracristal VSD patients. Two eccentric occluders were implanted in 1 perimembranous and 1 intracristal VSD patient since the rim to the aortic valve distance was <2 mm. Moreover, 2 asymmetrical occluders were used in 2 perimembranous multi-hole VSDs. Immediate procedure and 16.1±9.9 months’ follow-up outcomes showed no device dislodgement and embolism, no new-onset aortic valve regurgitation, and no atrioventricular heart block. Conclusions. Transcatheter perimembranous and intracristal VSD closure via femoral vein alone under the TTE guidance is feasible and safe in eligible patients. The new type of multipurpose specialized catheter will facilitate this procedure.
An unexpected finding in a patient with aortic stenosis following TAVI
Sandya Nandakumar
Sergio Lamas

Sandya Nandakumar

and 5 more

August 28, 2022
Coronary cusp tear is a very rare complication after transcatheter aortic valve implantation (TAVI). We present the case of an 85-year old male with native aortic valve cusp tear following TAVI. Our case highlights the advantage of transthoracic and transoesophageal echocardiography as an easily accessible and affordable imaging modality to access complications that can occur after TAVI.
Transition from ICU to Portable home ventilator (PHV) in children with severe Broncho...
Amit Agarwal
Robin McKinney

Amit Agarwal

and 1 more

August 28, 2022
As the population of ventilator-dependent children (VDC) with tracheostomies due to underlying severe BPD grows, there is an increasing need to shift the care of these children from hospital to home. Transitioning the ventilator-dependent child from the hospital to home is a complex process that requires coordination between the medical team and the family. One crucial step in the process is transitioning from an Intensive care unit (ICU) ventilator to a portable home ventilator (PHV). The Clinical team needs to understand the nuances in transitioning to PHV, including assessing readiness to transition and choosing the optimum settings on an available home ventilator. In recent years, various ventilator modes have been available in PHV that can help achieve synchronous breathing to allow for adequate gas exchange for the infant. This review details some approaches to asses readiness to transition and the process of Transition along with commonly used modes of support available in PHV, as well as the primary and secondary settings in which we should be mindful in supporting a child with chronic respiratory failure in the home setting.
Association of CFTR activity in sweat test, NPD, and ICM with ivacaftor and lumacafto...
Christian Dopfer
Rainer Trittler

Christian Dopfer

and 10 more

August 28, 2022
Combination therapy with the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) corrector lumacaftor and the CFTR potentiator ivacaftor has demonstrated significant impact on clinical parameters in Phe508del homozygous people with CF. Whether these changes under treatment are correlated to serum levels of both drugs had yet to be investigated. We therefore analyzed data from our previous study (OrkambiFacts, ClinicalTrials.gov Identifier: NCT02807415). In summary, we did not find statistically significant correlations between serum drug levels and changes in clinical parameters and biomarkers of CFTR function such as FEV1, BMI, sweat chloride, nasal potential difference (NPD) and intestinal current measurement (ICM). Absolute blood levels of lumacaftor or ivacaftor do not seem to be informative biomarkers to predict clinical improvement or the attenuation of the basic defect.
Peak Expiratory Flow Rate and its variations in normal school going children aged 9 t...
avneet kaur
amarpreet kaur

avneet kaur

and 3 more

August 28, 2022
Among various pulmonary function tests used to assess the functioning of lungs, peak expiratory flow rate (PEFR) measurement is simple, reproducible and reliable way of judging the degree of airway obstruction in various obstructive pulmonary diseases like asthma. This study was conducted in various schools of rural and urban areas of Faridkot district of Punjab, India on one thousand normal healthy school going children of age group of 9 to 15 years. Characteristics of study population like socioeconomic status, exposure to tobacco smoke, participation in outdoor sports, type of cooking fuel used at home etc. was noted in proformas. Readings were taken in three different seasons over a period of one-year to observe seasonal variations. The mean age of boys (498) and girls (502) from rural (500) and urban (500) areas was 11.948±1.220 years. Boys had higher mean PEFR value than girls (p<0.05). Mean PEFR of boys was more than girls at a given age group, at given height interval and weight (p <0.05). PEFR increased in both boys and girls with increase in age, height and weight (p<0.05). There was no significant difference in PEFR values of children living in rural and urban areas (p= 0.681) Children belonging to different socioeconomic statuses had significant difference in PEFR values (p value=0.008). PEFR was significantly higher in children participating in outdoor sports than those who didn’t participate in any sports(p value=0.005). No significant variation of PEFR was seen with season, exposure to tobacco smoke and cooking fuel used at home.
Patient and caregiver perceptions of airway clearance methods used for cystic fibrosi...
Anthony Fischer
Zoe Kienenberger

Anthony Fischer

and 9 more

August 28, 2022
Introduction: Cystic Fibrosis Foundation guidelines recommend people with CF perform daily airway clearance. This can be difficult for patients to complete, as some find it time consuming or uncomfortable. Data comparing airway clearance methods are limited. We surveyed patients and families to understand which methods are preferred and identify obstacles performing airway clearance. Methods: We designed a REDCap survey and enrolled participants in 2021. Respondents reported information on airway clearance usage, time commitment, and medication use. They rated airway clearance methods for effectiveness, comfort, time commitment, importance, and compatibility with other treatments. Analysis included descriptive statistics and clustering. Results: 60 respondents started and 52 completed the survey. The median patient age was 20 years. Respondents experienced a median of four airway clearance methods in their lifetime, including chest wall oscillation (vest, 92%), manual chest physical therapy (CPT, 88%), huff coughing (77%), and exercise (75%). Past 30-day use was highest for exercise (62%) and vest (57%). Time commitment was generally less than 2 hours daily. Of those eligible for CFTR modulators, 53% reported decreased time commitment to airway clearance after starting treatment. On a scale of 0-100, respondents rated CFTR modulators as their most important treatment (median 99.5), followed by exercise (88). Discussion: Patients and caregivers are familiar with several methods of airway clearance for CF. They report distinct strengths and limitations of each method. Exercise and vest are the most common methods of airway clearance. Use of CFTR modulators may reduce patient-reported time commitment to airway clearance.
INVESTIGATION OF PHAGOCYTE FUNCTIONS IN PSEUDOMONAS-COLONIZED CYSTIC FIBROSIS PATIENT...
Handan Duman
Meral Barlik

Handan Duman

and 7 more

August 28, 2022
Introduction: Cystic fibrosis (CF) is an autosomal recessive disorder. Although it is considered as an epithelial disease due to impaired chloride transport, its pathogenesis is not clear. CF is classified as a syndrome with congenital defects of phagocyte in recent human inborn errors of immunity phenotypic classification. Neutrophils are the most effective cells in the eradication of bacterial infections such as Pseudomonas aeruginosa. The aim of this study was to investigate the phagocyte functions in pseudomonas colonized cystic fibrosis patients. Material-Method: A total number of 26 Pseudomonas colonized cystic fibrosis patients and 21 healthy controls (sex and age matched) were included in the study. Absolute neutrophil counts(ANC), immunoglobulin values (Ig), Migratest to evaluate chemotaxis in neutrophils and monocytes, CD11A/CD18/CD15 S (β2 integrin) adhesion molecules, Phagoburst test for intracellular bacterial killing were analyzed by flow cytometer. Results:  Absolute neutrophil counts (ANC), CD15S expression on neutrophils and IgG, IgA and IgM levels were higher in CF patients than control group (p<0.01, 0,018). The neutrophils oxidative burst activity and chemotactic ability of CF patients did not differ from that of controls. Patients with Allergic Bronchopulmonary Aspergillosis (ABPA) and with a mutation of 2183AA>G had significantly lower chemotaxis index than the others (respectively p:0.01, p:0.01). Conclusion: Our results from a small group of patients does not support impaired functions such as migration and phagocytosis of neutrophils in patients with CF. Further studies involving more CF patients are needed to make a definitive interpretation.
Urinary cotinine levels show high concordance with tobacco exposure and lower oxygen...
Cansu Altuntaş
Pelin Zorlu

Cansu Altuntaş

and 1 more

August 28, 2022
Childhood pneumonia is an important issue causing morbidity and mortality especially in developing countries. Secondhand smoking has been shown to increase the risk of lower respiratory tract diseases, especially in children under 2 years of age. In epidemiological studies, secondhand smoking is evaluated mostly by measuring cotinine level in urine. The aim of this study is to determine the environmental tobacco exposure status of otherwise healthy infants who were admitted to the hospital due to community-acquired lower respiratory tract infection and to investigate the effects of environmental tobacco exposure on clinical parameters, laboratory findings and hospitalization periods. When daily household tobacco consumption and the distribution of cotinine was compared, greater consumption was found to be statistically significantly associated with cotinine elevation (n =115, p=0.001). No significant relationship was found between the likelihood of high cotinine levels and the proximity of tobacco consumption to the child (n=86, p = 0.501). Among all participants urinary cotinine elevation was significantly correlated with lower oxygen saturation levels (p = 0.038) at admission. In this study, it is shown that exposure from surfaces previously exposed to tobacco smoke (environmental tobacco exposure) is also an important parameter that affects infants’ clinical status and must be considered a negative prognostic factor during evaluation of an infant with community acquired lower respiratory system infection. It is imperative to create a strict smoke-free, tobacco exposure-free environment for improved infant health in the community.
Responses of carbon dynamics to grazing exclusion in alpine grassland ecosystems on t...
Jian Sun
Tianyuan Liu

Jian Sun

and 10 more

August 28, 2022
In the context of “Carbon Emissions Peak” and “Carbon Neutrality”, grazing exclusion (GE) has been applied widely to rehabilitate degraded grasslands and increase carbon sequestration. However, on the Qingzang Plateau (QP), the impacts of GE on carbon dynamics of alpine grasslands are poorly understood, particularly at regional scale. Here, we evaluated the responses of carbon sequestration to GE in different alpine grasslands across QP to fill this knowledge gap by using meta-analysis. Overall, the effects of GE on ecosystem carbon fractions were dependent on GE duration, grassland types and climate factors. GE had more obviously positive effects on carbon stock across alpine meadow than alpine steppe. Longer duration of GE was more effective for ecosystem carbon sequestration in alpine steppe. Annual mean precipitation (AMP) and temperature (AMT) began to dominate ecosystem carbon sequestration after three years of GE duration across alpine meadow; and AMP was important climate factor limiting ecosystem carbon sequestration in the alpine steppe. In terms of plant carbon fraction, GE generated continuous positive effects on aboveground biomass (AGB) with increased GE duration in alpine meadow, while the continuous beneficial effects for AGB of alpine steppe disappeared at the 8th year of GE duration. And no positive effects were found on belowground biomass at the 11th year in both alpine meadow and alpine steppe. For soil organic carbon and microbial biomass carbon, there were no obvious trends in response to GE duration. In general, we highlighted that the responses of different carbon fractions (plant -soil - microbe) to GE were nonuniform at spatial and temporal scales, thereby we should adopt different carbon management practices for sustainable development of different grasslands.
Cyclic Extrusion Synthesis of Mesoporous Carbon-Supported Metal Catalysts for Selecti...
Pengfei Zhang
Jialu Xu

Pengfei Zhang

and 4 more

August 28, 2022
The mesoporous carbon-supported metal catalysts are important materials in heterogeneous catalysis. From the standpoint of process intensification, the current synthesis methods still suffer from several issues, such as the excessive use of toxic solvents, the time-consuming self-assembly process, and the difficulty of continuous production. Herein, we report a solvent-free and continuous route to synthesize mesoporous carbon-supported metal catalysts. Interestingly, the use of cyclic extrusion could promote the mixing, coordination, and assembly of catalyst precursors (tannin-metal salts-additives) by shearing and squeeze force. The as-made mesoporous carbon-supported nickel showed high surface areas (up to 512m2g-1), narrow pore size distribution (~10 nm), and good performance in the selective hydrogenation of nitrobenzene to aniline (Conv.>99%; Sel.>99%). In addition, the fluid property of catalyst precursors and the geometry of the twin-screw extrusion channel were studied, and the essence of this cyclic extrusion process is also discussed.
The glycogen cargo receptor STBD1: from biology to disease targeted therapies
Qiannan Tang
Meiqing Liu

Qiannan Tang

and 3 more

August 27, 2022
Glycophagy is a novel selective autophagy characterized by glycogen degradation via the lysosomal enzyme acid α-glucosidase (GAA). Starch-binding domain-containing protein 1 (STBD1) is a glycogen cargo receptor that mediates glycophagy through binding glycogen transport into lysosomes. STBD1-dependent glycophagy has garnered considerable interest in the pathology community, because its dysregulation causes multiple diseases, with cancer being the most serious. Notably, deletions and/or mutations in STBD1 promote tumorigenesis. In this review, we first summarized the current understanding of STBD1, including its structure, subcellular localization, tissue distribution, and biological functions. Next, we examined the roles and molecular mechanisms of STBD1-dependent glycophagy in various diseases (e.g., Pompe disease, Parkinson’s disease, cardiac diseases, and cancer). Based on available research, we discussed the promising function and future of STBD1, including its potential application as a therapeutic target in glycogen-related diseases. We recommend using real-time diagnostic tools to observe the progression of STBD1-mediated glycophagy and gain further insight on the mechanism of action. Such details are needed to investigate new avenues for glycogen-related disease therapy.
Identifying the core concepts of pharmacology education: a global initiative
Paul White
Clare Guilding

Paul White

and 32 more

August 27, 2022
Background and Purpose: In recent decades, a focus on the most critical and fundamental concepts has proven highly advantageous to students and educators in many science disciplines. Pharmacology, unlike microbiology, biochemistry or physiology, lacks a consensus list of such core concepts. Experimental approach: We sought to develop a research-based, globally relevant list of core concepts that all students completing a foundational pharmacology course should master. This two-part project consisted of exploratory and refinement phases. The exploratory phase involved empirical data mining of the introductory sections of five key textbooks, in parallel with an online survey of over 200 pharmacology educators from 17 countries across six continents. The refinement phase involved three Delphi rounds involving 24 experts from 15 countries across six continents. Key Results: The exploratory phase resulted in a consolidated list of 74 candidate core concepts. In the refinement phase, the expert group produced a consensus list of 25 core concepts of pharmacology. Conclusion and Implications: This list will allow pharmacology educators everywhere to focus their efforts on the conceptual knowledge perceived to matter most by experts within the discipline. Next steps for this project include defining and unpacking each core concept and developing resources to help pharmacology educators globally teach and assess these concepts within their educational contexts.
CMMSE: A low-dimensional realization algorithm for periodic input/output behavioral s...
José Aleixo
Paula Rocha

José Aleixo

and 1 more

August 27, 2022
The state-space realization of linear systems is of utmost importance in linear systems theory. After the realization problem for the time-invariant case has been solved, particular attention was paid to the case of linear periodic systems (see, e.g. 1,2,3,4,5,6,7,8). Recently, such systems have regained importance, for instance, in the context of coding theory (see9), where periodic convolutional encoders play an important role, 10. The majority of the contributions within this area concern the realization of transfer functions as well as impulse responses, thus excluding the case of input/output linear systems without coprime representations. By the end of the eighties of the last century, Jan C. Willems (see11,12) suggested an approach (nowadays known as the behavioral approach) that considers a wider class of systems and allows to overcome this drawback. According to this approach, the central object in a system is its behavior which consists of all the signals that satisfy the system laws (also called system trajectories). Consequently, the behavior of a system with an input/output representation that is not coprime, contains more trajectories than the set of input/output signals defined by the system transfer function. Our work takes this fact into account. Based on results already obtained in 13,14, we revisit the problem of the realization of linear periodic MIMO behaviors and give further insight into this problem, which allows setting up an algorithm to compute a low-dimensional state-space realization of a periodic behavior. The proposed algorithm is based on a chain decomposition of suitable matrices.
Validation of the accuracy of contact force measurement by contemporary force-sensing...
Thomas Küffer
Andreas Haeberlin

Thomas Küffer

and 9 more

August 27, 2022
Introduction: Contact force-sensing catheters are widely used for ablation of cardiac arrhythmias. They allow quantification of catheter-to-tissue contact, which is an important determinant for lesion formation and may reduce the risk of complications. The accuracy of these sensors may vary across the measurement range, catheter-to-tissue angle, and amongst manufacturers and we aim to compare the accuracy and reproducibility of four different force sensing ablation catheters. Methods: A measurement setup containing a heated saline water bath with an integrated force measurement unit was constructed and validated. Subsequently, we investigated four different catheter models, each equipped with a unique measurement technology: Tacticath Quartz (Abbott), AcQBlate Force (Biotronik/Acutus), Stablepoint (Boston Scientific), and Smarttouch SF (Biosense Webster). For each model, the accuracy of three different catheters was measured within the range of 0-60 grams and at contact angles of 0°, 30°, 45°, 60°, and 90°. Results: In total, 6685 measurements were performed using 4x3 catheters (median of 568, IQR 511-606 measurements per catheter). Over the entire measurement-range, the force measured by the catheters deviated from the real force by the following absolute mean values: Tacticath 1.29g ±0.99g, AcQBlate Force 2.87g ±2.37g, Stablepoint 1.38g ±1.29g, and Smarttouch 2.26g ±2.70g. For some models, significant under- and overestimation of >10g were observed at higher forces. Mean absolute errors of all models across the range of 10-40g were <3g. Conclusion: Contact measured by force-sensing catheters is accurate with 1-3g deviation within the range of 10g to 40g. Significant errors can occur at higher forces with potential clinical consequences.
3D structure - 2D plate - 1D rod interaction problem
Matko Ljulj
Josip Tambaca

Matko Ljulj

and 1 more

August 27, 2022
In this paper we consider the equilibrium problem of interaction of three elastic bodies of different elastic properties. The main body is the unit cube. On top of it is a thin layer/quboid of thickness $\eps$ of material whose stiffness is of order $\frac{1}{\eps}$ that in the middle contains another cuboid which is of width and thickness $\eps$ that is made of material with elasticity coefficients of order $\frac{1}{\eps^q}$ for $q>0$. We show that the family of solutions of linearized elasticity problems, when $\eps$ tends to zero, converges to a solution of a problem that is posed only on the unit cube with possibly additional elastic terms on the boundary related to the plate/rod energy of the thin elastic parts. It turns out that there are five different regimes related to different values of $q$ ($q\in \langle 0, 2\rangle, \{2\}, \langle 2, 4\rangle,\{4\},\langle 4, \infty\rangle$) with different limit problems. We further formulate a model posed on the unit cube that has the same asymptotics when $\eps$ tends to zero as the full 3d problem posed on the union of the unit cube and thin cuboids. This model then can be used as the approximating model in all regimes.
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