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1.
Ann Med Surg (Lond) ; 86(7): 3880-3886, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38989172

RESUMO

Background: Syncope is a serious consequence in patients with hypertrophic obstructive cardiomyopathy (HOCM). Percutaneous endocardial septal radiofrequency ablation (PESA) has emerged as a promising intervention to alleviate symptoms and enhance the quality of life for HOCM patients. However, little is known about the effects of PESA on syncope in HOCM. The authors aimed to study the effects of PESA on syncope in patients with HOCM. Materials and methods: Nineteen patients with HOCM and syncope were enrolled. The left ventricular outflow tract gradient (LVOTG) of the patients was more than 50 mmHg despite medication. The participants underwent PESA under the guidance of intracardiac echocardiography (ICE) combined with a three-dimensional electrophysiological mapping system. The patients were followed for 3 (3-5.5) months. Results: The mean age of the patients was 54.8±13.7 years. Out of the 19 participants, 7 (37%) were females. During the follow-up, the syncope was completely alleviated in 14 patients (73.7%) or the syncope episodes were reduced greater than or equal to 80% in 16 patients (84.2%). The mean NYHA functional class significantly improved from 2.2±0.7 at baseline to 1.7±0.6 during follow-up (P=0.002). The LVOTG and septal thickness showed a decreasing trend from baseline to follow-up (LVOTG: P=0.083, septal thickness: P=0.086). Conclusion: The authors' investigation provides evidence supporting the effectiveness of PESA in reducing syncope episodes in patients with HOCM.

2.
BMC Cardiovasc Disord ; 24(1): 340, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970012

RESUMO

Atrial flutter, a prevalent cardiac arrhythmia, is primarily characterized by reentrant circuits in the right atrium. However, atypical forms of atrial flutter present distinct challenges in terms of diagnosis and treatment. In this study, we examine three noteworthy clinical cases of atypical atrial flutter, which offer compelling evidence indicating the implication of the lesser-known Septopulmonary Bundle (SPB). This inference is based on the identification of distinct electrocardiographic patterns observed in these patients and their favorable response to catheter ablation, which is a standard treatment for atrial flutter. Remarkably, in each case, targeted ablation at the anterior portion of the left atrial roof effectively terminated the arrhythmia, thus providing further support for the hypothesis of SPB involvement. These insightful observations shed light on the potential significance of the SPB in the etiology of atypical atrial flutter and introduce a promising therapeutic target. We anticipate that this paper will stimulate further exploration into the role of the SPB in atrial flutter and pave the way for the development of targeted ablation strategies.


Assuntos
Potenciais de Ação , Flutter Atrial , Ablação por Cateter , Eletrocardiografia , Frequência Cardíaca , Flutter Atrial/fisiopatologia , Flutter Atrial/diagnóstico , Flutter Atrial/cirurgia , Flutter Atrial/terapia , Flutter Atrial/etiologia , Humanos , Masculino , Resultado do Tratamento , Pessoa de Meia-Idade , Feminino , Idoso , Pericárdio/fisiopatologia , Técnicas Eletrofisiológicas Cardíacas
3.
J Am Heart Assoc ; : e034080, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056345

RESUMO

BACKGROUND: Percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) has been reported to be safe and effective at midterm follow-up to treat drug-refractory hypertrophic obstructive cardiomyopathy in a single center. However, data from other centers are lacking. This retrospective cohort study aimed to investigate the efficacy and safety of PIMSRA from another independent center. METHODS AND RESULTS: PIMSRA was performed in 76 patients with hypertrophic obstructive cardiomyopathy in our center from April 2020 to June 2023. The primary outcome was the reduction of left ventricular outflow tract gradient after 6 months or more post-PIMSRA. Secondary outcomes were periprocedural major adverse clinical events. Sixty-one patients returned to the hospital for follow-up 6 to 30 (median, 14) months after the procedure. At the last follow-up of the 61 patients, the maximum septal thickness decreased from a median of 23.6 (interquartile range, 20.5-26.4) to 19.1 (interquartile range, 16.0-22.1) mm (P<0.001) and the left ventricular outflow tract peak gradient at rest decreased from a median of 70.0 (interquartile range, 29.1-107.5) to 20.0 (interquartile range, 10.8-48.8) mm Hg (P<0.001). The percentage of patients with symptoms of New York Heart Association functional class III/IV decreased from 51% to 0%. Of all 76 patients, there was no in-hospital or 30-day death, no right or left branch block, and no permanent pacemaker implantation. Six (8%) patients had pericardial effusion, with 1 experiencing cardiac tamponade and ventricular fibrillation, and 1 (1%) patient developed septal branch aneurysm that was treated with coil occlusion. CONCLUSIONS: PIMSRA allows for the reduction in the left ventricular outflow tract gradient and enhances symptomatic improvement, with a limited incidence of adverse events and complications among patients with hypertrophic obstructive cardiomyopathy.

4.
Cardiovasc Res ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028686

RESUMO

AIMS: Circular RNAs (circRNAs) are considered important regulators of biological processes, but their impact on atherosclerosis development, a key factor in coronary artery disease (CAD), has not been fully elucidated. We aimed to investigate their potential use in patients with CAD and the pathogenesis of atherosclerosis. METHODS AND RESULTS: Patients with stable angina (SA) or acute coronary syndrome (ACS) and controls were selected for transcriptomic screening and quantification of circRNAs in blood cells. We stained carotid plaque samples for circRNAs and performed gain- and loss-of-function studies in vitro. Western blots, protein interaction analysis, and molecular approaches were used to perform the mechanistic study. ApoE-/- mouse models were employed in functional studies with adeno-associated virus-mediated genetic intervention. We demonstrated elevated circARCN1 expression in peripheral blood mononuclear cells from patients with SA or ACS, especially in those with ACS. Furthermore, higher circARCN1 levels were associated with a higher risk of developing SA and ACS. We also observed elevated expression of circARCN1 in carotid artery plaques. Further analysis indicated that circARCN1 was mainly expressed in monocytes and macrophages, which was also confirmed in atherosclerotic plaques. Our in vitro studies provided evidence that circARCN1 affected the interaction between HuR and ubiquitin-specific peptidase 31 (USP31) mRNA, resulting in attenuated USP31-mediated NF-κB activation. Interestingly, macrophage accumulation and inflammation in atherosclerotic plaques were markedly decreased when circARCN1 was knocked down with adeno-associated virus in macrophages of ApoE-/- mice, while circARCN1 overexpression in the model exacerbated atherosclerotic lesions. CONCLUSIONS: Our findings provide solid evidence macrophagic-expressed circARCN1 plays a role in atherosclerosis development by regulating HuR-mediated USP31 mRNA stability and NF-κB activation, suggesting that circARCN1 may serve as a factor for atherosclerotic lesion formation.

5.
Phys Chem Chem Phys ; 26(26): 18076-18088, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38895812

RESUMO

This work presents an in-depth investigation into the cracking reaction mechanism of phenylpentazole (C6H5N5) under the catalytic influence of sodium metal, utilizing density functional theory. The geometries of the reactants, transition states, intermediates, and products are meticulously optimized employing the GGA/PW91/DNP level of theory. Also, a rigorous analysis is undertaken, encompassing various key factors including configuration parameters, Mulliken charges, densities of states, and reaction energies. Three distinct reaction pathways are comprehensively examined, shedding light on the intricate details and intricacies of each pathway. The results show that a remarkable outcome in which the activation energy of the C6H5N5 cracking reaction releases N2, facilitated by catalytic metal Na, reveals a strikingly reduced value of a mere 5.2 kcal mol-1 compared to the previously reported activation energies ranging from 20 to 30 kcal mol-1. Evidently, this significantly lowered barrier can be readily surpassed at typical room temperatures, exhibiting practical applicability. Notably, the alkali metal Na effectively serves as a catalyst, successfully diminishing the activation energy required for N2 production through the pyrolysis of pentazole compounds. This breakthrough discovery provides a theoretical basis for experimental research on the low-temperature cracking of pentazole compounds. It also offers valuable insights for the development and application of new high energy density materials, contributing to the creation of a green and low-carbon circular economic system.

6.
Materials (Basel) ; 17(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38893977

RESUMO

The fatigue performance of hard asphalt is an important factor that affects the service life of asphalt pavement. In order to comprehensively explore the influence of chemical components on the fatigue performance of hard asphalt, and to eliminate the chemical instability between the microstructure of asphalt from different oil sources, seven kinds of hard asphalt were designed and prepared with saturates, aromatics, resins, and asphaltenes (SARA) extracted from the same hard asphalt. Rheological, time sweep and linear amplitude sweep (LAS) tests were carried out to evaluate the fatigue properties. The results show that the complex modulus of asphalt binds increased rapidly with an increase of asphaltene and resins and that the colloidal structure was strengthened, which would increase the fatigue factor. In the time sweep test, the strength of the colloidal structure significantly affected the fatigue life, and the fatigue life was different under different test stresses. In the viscoelastic continuum damage (VECD) model, the cumulative damage was related to the modulus, while with the increase of asphaltene and resins, the fatigue life showed a trend of first increasing and then decreasing. The linear regression analysis showed that the fatigue life of hard asphalt had a good correlation with strain sensitivity. This study investigated the applicability of different fatigue evaluation methods and revealed the influence of four components on the fatigue properties of hard asphalt. The results provide significant insights in the improvement of the fatigue performance of both hard asphalt and corresponding mixtures.

7.
iScience ; 27(6): 109849, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38784008

RESUMO

Cholesterol efflux capacity (CEC) dysfunction in macrophages is important in atherosclerosis. However, the mechanism underlying CEC dysfunction remains unclear. We described the characteristics of ATF4 and inflammasome activation in macrophages during atherosclerosis through scRNA sequencing analysis. Then model of hyperlipemia was established in ApoE-/- mice; some were treated with tauroursodeoxycholic acid (TUDCA). TUDCA decreased the ATF4, Hspa, and inflammasome activation, reduced plaque area of the artery, and promoted CEC in macrophages. Furthermore, TUDCA abolished oxLDL-induced foam cell formation by inhibiting activation of the PERK/eIF2α/ATF4 and AIM2 inflammasome in macrophages. Further assays revealed ATF4 binding to AIM2 promoter, promoting its transcriptional activity significantly. Then we discovered that ATF4 affected AIM2-mediated foam cell formation by targeting ABCA1, which could be blocked by TUDCA. Our study demonstrated that TUDCA alleviates atherosclerosis by inhibiting AIM2 inflammasome and enhancing CEC of macrophage, which provided possibilities for the development of therapies.

8.
J Thorac Dis ; 16(4): 2341-2352, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38738257

RESUMO

Background: Intracardiac echocardiography (ICE) is a novel technology with certain advantages in treatment of atrial fibrillation (AF), yet there is limited research on the use of ICE in radiofrequency ablation for AF treatment in China. The aim of this study was to investigate the total fluoroscopy time and dose, safety, and effectiveness of ICE guided vs. traditional fluoroscopy (non-ICE) guided radiofrequency ablation for AF in China. Methods: We conducted a single-center retrospective analysis of patients who underwent ICE or traditional fluoroscopy-guided radiofrequency ablation for AF. The primary endpoint of this study was total fluoroscopy time, and the secondary endpoints included total fluoroscopy dose, acute surgery failure, transseptal puncture time, ablation time, total procedure time, and 6-month surgery success (no AF recurrence or atrial flutter). As an exploratory analysis, outcomes of interest by different types of AF were examined. Results: A total of 97 patients were included in the analysis. Forty-eight were in the ICE group and 49 were in the non-ICE group with comparable demographic and clinical characteristics at the baseline. None of patients experienced acute surgery failure with no major procedure-related complications occurred. The fluoroscopic time and dose were significantly lower in the ICE group compared to the non-ICE group (0.00 vs. 9.67±4.88 min, P<0.001; 0.00 vs. 77.10±44.28 mGy/cm2, P<0.001, respectively). There were no statistically significant differences in transseptal puncture time, ablation time and total procedure time between the two groups. There were two AF recurrences observed during the 6-month follow-up in each group (P>0.99). Conclusions: ICE significantly reduced the fluoroscopic time and dose for radiofrequency catheter ablation in AF patients. There were no significant differences in safety or effectiveness outcomes between the ICE and non-ICE groups.

9.
Int J Cardiol Heart Vasc ; 52: 101422, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38756452

RESUMO

Background: Systemic inflammation has been proposed to be associated with the incidence of atrial fibrillation (AF), but whether it is a cause or a consequence of AF remains uncertain. We sought to explore the causal associations between systemic inflammation and AF using bidirectional Mendelian randomization (MR) analysis. Methods: Independent genetic variants strongly associated with AF were selected as instrumental variables from the largest genome-wide association study (GWAS) with up to 1,030,836 individuals. Regarding inflammation traits, genetic associations with 41 inflammatory cytokines and 5 inflammatory biomarkers were obtained from their corresponding GWASs databases. Effect estimates were primarily evaluated using the inverse-variance weighted (IVW) method, supplemented by sensitivity analyses using MR-Egger, weighted median, and MR-PRESSO methods. Results: In our initial MR analyses, we observed suggestive associations of genetically predicted interleukin-17 (IL-17), interleukin-2 receptor subunit alpha (IL-2rα), and procalcitonin (PCT) with AF. One standard deviation (SD) increase in IL-17, IL-2rα, and PCT caused an increase in AF risk by 6.3 % (OR 1.063, 95 %CI 1.011---1.118, p = 0.018), 4.9 % (OR 1.049, 95 %CI 1.007---1.094, p = 0.023) and 3.4 % (OR 1.034, 95 %CI 1.005---1.064, p = 0.022), respectively. Furthermore, our reverse MR analyses indicated that genetically predicted AF contributed to a suggestive increase in the levels of macrophage inflammatory protein-1ß (MIP1ß) (ß 0.055, 95 %CI 0.006 to 0.103, p = 0.028), while a decrease in the levels of fibrinogen (Fbg) (ß -0.091, 95 %CI -0.140 to -0.041, p < 0.001), which remained significant after multiple test correction. Conclusions: Our MR study identified several inflammatory biomarkers with suggestive causal associations regarding the upstream and downstream regulation of AF occurrence, offering new insights for therapeutic exploitation of AF. Further research is required to validate the underlying link between systemic inflammation and AF in larger cohorts.

10.
Heart Rhythm ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38588992

RESUMO

BACKGROUND: The aorta-mitral annulus conjunction (AMC) is an uncommon site of origin of focal atrial tachycardias (ATs). Hence, the electrophysiological and ablation target characteristics are poorly described. OBJECTIVE: The purpose of this study was to describe the characteristics of AMC ATs in detail. METHODS: The study enrolled 650 patients with ATs, 21 (3.2%) of whom had ATs originating from the AMC. A comprehensive evaluation, including electrocardiography, electrophysiology study, computed tomography scan, and intracardiac echocardiography, was performed. RESULTS: The majority (19, 90.5%) of ATs occurred spontaneously. The mean age of this group was 48.9 ± 21.6 years, with 12 being female (57.1%). Seventeen patients had a typical biphasic P wave with a prominent positive component. The earliest activation site in the right atrium was near the His bundle, with average activation -10.3 ± 6.0 ms preceding the P wave. The successful ablation targets were distributed as follows: 1 case at 9 o'clock, 6 cases at 10 o'clock, 7 cases at 11 o'clock, 6 cases at 12 o'clock, and 1 case in the left coronary cusp. The local AMC potential differed from the commonly perceived annular potential and was characterized by a prominent A wave and a smaller V wave (atrial-to-ventricular ratio > 1). The angle of encroachment on the left atrial anterior wall, compressed by the left coronary cusp, was significantly smaller in the AMC ATs group than in the control group consisted of 40 patients who underwent coronary artery CT scans because of the chest pain but without atrial arrhythmias were randomly selected, which may have contributed to the arrhythmia substrate (141.7° ± 11.5° vs 155.2° ± 13.9°; P = .026). CONCLUSION: A new strategy for mapping AMC ATs has been introduced. The ablation target should have an atrial-to-ventricular ratio of >1.

11.
Europace ; 26(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38466042

RESUMO

AIMS: Premature ventricular contractions (PVC) and non-sustained ventricular tachycardia (NSVT) are commonly observed in light chain cardiac amyloidosis (AL-CA), but their association with prognosis is still unclear. We aimed to evaluate the prognostic value of PVCs and NSVT in patients with moderate-to-advanced AL-CA. METHODS AND RESULTS: We retrospectively included patients with AL-CA at modified 2004 Mayo stages II-IIIb between February 2014 and December 2020. Twenty-four-hour Holter recordings were assessed on admission. The outcomes included (i) new onset of adverse ventricular arrhythmia (VA) or sudden cardiac death (SCD) and (ii) cardiac death during follow-up. Of the 143 patients studied (60.41 ± 11.06 years, male 64.34%), 132 (92.31%) had presence of PVC, and 50 (34.97%) had NSVT on Holter. Twelve (8.4%) patients died in hospital and 131 patients were followed up (median 24.4 months), among whom 71 patients had cardiac death, and 15 underwent adverse VA/SCD. NSVT [hazard ratio (HR): 13.57, 95% confidence interval (CI): 3.06-60.18, P < 0.001], log-transformed PVC counts (HR: 1.46, 95%CI: 1.15-1.86, P = 0.002) and PVC burden (HR: 1.43 95%CI:1.14-1.80, P = 0.002) were predictive of new onset of adverse VA/SCD. The highest tertile of PVC counts (HR: 2.33, 95%CI: 1.27-4.28, P = 0.006) and PVC burden (HR: 2.58, 95%CI: 1.42-4.69, P = 0.002), rather than NSVT (HR: 1.16, 95%CI: 0.67-1.98, P = 0.603), was associated with cardiac death. Higher PVC counts/burden provided incremental value on modified 2004 Mayo stage in predicting cardiac death, with C index increasing from 0.681 to 0.712 and 0.717, respectively (P values <0.05). CONCLUSION: PVC count, burden, and NSVT significantly correlated with adverse VA/SCD during follow-up in patients with AL-CA. Higher PVC counts/burdens added incremental value for predicting cardiac death.


Assuntos
Taquicardia Ventricular , Complexos Ventriculares Prematuros , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Eletrocardiografia Ambulatorial , Morte Súbita Cardíaca
12.
Int J Cardiol ; 405: 131982, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38521511

RESUMO

BACKGROUND: A model developed specifically for stable coronary artery disease (SCAD) patients to predict perioperative major adverse cardiovascular events (MACE) has not been previously reported. METHODS: The derivation cohort consisted of 5780 patients with SCAD undergoing noncardiac surgery at the First Affiliated Hospital of Zhejiang University School of Medicine, from January 1, 2013 until May 31, 2021. The validation cohort consisted of 2677 similar patients from June 1, 2021 to May 31, 2023. The primary outcome was a composite of MACEs (death, resuscitated cardiac arrest, myocardial infarction, heart failure, and stroke) intraoperatively or during hospitalization postoperatively. RESULTS: Six predictors, including Creatinine >90 µmol/L, Hemoglobin <110 g/L, Albumin <40 g/L, Leukocyte >10 ×109/L, high-risk Surgery (general abdominal or vascular), and American Society of Anesthesiologists (ASA) class (III or IV), were selected in the final model (CHALSA score). Each patient was assigned a CHALSA score of 0, 1, 2, 3, or > 3 according to the number of predictors present. The incidence of perioperative MACEs increased steadily across the CHALSA score groups in both the derivation (0.5%, 1.4%, 2.9%, 6.8%, and 23.4%, respectively; p < 0.001) and validation (0.3%, 1.5%, 4.1%, 9.2%, and 29.2%, respectively; p < 0.001) cohorts. The CHALSA score had a higher discriminatory ability than the revised cardiac risk index (C statistic: 0.827 vs. 0.695 in the validation dataset; p < 0.001). CONCLUSIONS: The CHALSA score showed good validity in an external dataset and will be a valuable bedside tool to guide the perioperative management of patients with SCAD undergoing noncardiac surgery.


Assuntos
Doença da Artéria Coronariana , Complicações Pós-Operatórias , Humanos , Masculino , Feminino , Doença da Artéria Coronariana/cirurgia , Doença da Artéria Coronariana/epidemiologia , Pessoa de Meia-Idade , Idoso , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/diagnóstico , Estudos de Coortes , Valor Preditivo dos Testes , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Medição de Risco/métodos , Estudos Retrospectivos , Fatores de Risco
13.
J Cardiovasc Transl Res ; 17(3): 732-738, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38180696

RESUMO

Hypertrophic cardiomyopathy (HCM) is associated with adverse outcomes, such as heart failure, arrhythmia, and mortality. Sudden cardiac death (SCD) is a common cause of death in HCM patients, and identification of patients at a high risk of SCD is crucial in clinical practice. The China Hypertrophic Cardiomyopathy Project is a hospital-based, multicenter, prospective, registry cohort study of HCM patients, covering a total of 3000 participants and with a 5-year follow-up plan. A large number of demographic characteristics and clinical data will be fully collected to identify prognostic factors in Chinese HCM patients. Furthermore, the main purpose of this study is to integrate demographic and clinical characteristics to establish new 5-year SCD risk predictive equations for Chinese HCM patients by the use of machine learning technologies. The project has crucial clinical significance for risk stratification and determination of HCM patients with high risk of adverse outcomes. CLINICAL TRIALS REGISTRATION: ChiCTR2300070909.


Assuntos
Cardiomiopatia Hipertrófica , Morte Súbita Cardíaca , Sistema de Registros , Humanos , Cardiomiopatia Hipertrófica/mortalidade , Cardiomiopatia Hipertrófica/epidemiologia , Cardiomiopatia Hipertrófica/terapia , Cardiomiopatia Hipertrófica/fisiopatologia , Cardiomiopatia Hipertrófica/diagnóstico , Estudos Prospectivos , China/epidemiologia , Medição de Risco , Morte Súbita Cardíaca/prevenção & controle , Morte Súbita Cardíaca/etiologia , Morte Súbita Cardíaca/epidemiologia , Fatores de Risco , Prognóstico , Fatores de Tempo , Masculino , Feminino , Projetos de Pesquisa , Pessoa de Meia-Idade , Adulto , Estudos Multicêntricos como Assunto , Aprendizado de Máquina , Idoso , Adulto Jovem
14.
Clin Cardiol ; 47(1): e24180, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37889106

RESUMO

BACKGROUND: Radiofrequency (RF) catheter ablation of para-Hisian accessory pathways (APs) can be challenging due to proximity to the conduction system. METHODS: A total of 30 consecutive patients with para-Hisian AP were enrolled for ablation in three centers, 12 (40%) of whom had previously failed attempted ablation from the inferior vena cava (IVC) approach. Ablation was preferentially performed using a superior approach from the superior vena cava (SVC) in all patients. RESULTS: The para-Hisian AP was eliminated from the SVC approach in 28 of 30 (93.3%) patients. In the remaining two patients, additional ablation from IVC was required to successfully eliminate the AP. There were two patients experienced reversible complete atrial-ventricular block and PR prolongation during the first RF application. Long-term freedom from recurrent arrhythmia was achieved in 29 (96.7%) patients over a mean follow-up duration of 15.6 ± 4.6 months. CONCLUSION: Catheter ablation of para-Hisian AP from above using a direct SVC approach is both safe and effective, and should be considered especially in patients who have failed conventional ablation attempts from IVC approach.


Assuntos
Feixe Acessório Atrioventricular , Ablação por Cateter , Humanos , Veia Cava Superior/diagnóstico por imagem , Veia Cava Superior/cirurgia , Resultado do Tratamento , Fascículo Atrioventricular , Sistema de Condução Cardíaco/cirurgia , Feixe Acessório Atrioventricular/cirurgia , Ablação por Cateter/efeitos adversos
15.
Small ; : e2310612, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087883

RESUMO

The biological system realizes the unity of action and perception through the muscle tissue and nervous system. Correspondingly, artificial soft actuators realize the unity of sensing and actuating functions in a single functional material, which will have tremendous potential for developing intelligent and bionic soft robotics. This paper reports the design of a laser-induced graphene (LIG) electrothermal actuator with self-sensing capability. LIG, a functional material formed by a one-step direct-write lasing procedure under ambient air, is used as electrothermal conversion materials and piezoresistive sensing materials. By transferring LIG to a flexible silicone substrate, the design ability of the LIG-based actuator unit is enriched, along with an effectively improved sensing sensitivity. Through the integration of different types of well-designed LIG-based actuator units, the transformations from multidimensional precursors to 2D and 3D structures are realized. According to the piezoresistive effect of the LIG units during the deformation process, the visual synchronous deformation state feedback of the LIG-based actuator is proposed. The multimodal crawling soft robotics and the switchable electromagnetic shielding cloak serve as the demonstrations of the self-sensing LIG-based actuator, showing the advantage of the design in remote control of the soft robot without relying on the assistance of visual devices.

16.
Europace ; 25(11)2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37971899

RESUMO

AIMS: Traditional ablation strategies including targeting the earliest Purkinje potential (PP) during left posterior fascicular (LPF) ventricular tachycardia (VT) or linear ablation at the middle segment of LPF during sinus rhythm are commonly used for the treatment of LPF-VT. Catheter ablation for LPF-VT targeting fragmented antegrade Purkinje (FAP) potential during sinus rhythm is a novel approach. We aimed to compare safety and efficacy of different ablation strategies (FAP ablation vs. traditional ablation) for the treatment of LPF-VT. METHODS AND RESULTS: Consecutive patients with electrocardiographically documented LPF-VT referred for catheter ablation received either FAP ablation approach or traditional ablation approach. Electrophysiological characteristics, procedural complications, and long-term clinical outcome were assessed. A total of 189 consecutive patients who underwent catheter ablation for LPF-VT were included. Fragmented antegrade Purkinje ablation was attempted in 95 patients, and traditional ablation was attempted in 94 patients. Acute ablation success with elimination of LPF-VT was achieved in all patients. Left posterior fascicular block occurred in 11 of 95 (11.6%) patients in the FAP group compared with 75 of 94 (79.8%) patients in the traditional group (P < 0.001). Fragmented antegrade Purkinje ablation was associated with significant shorter procedure time (94 ± 26 vs. 117 ± 23 min, P = 0.03) and fewer radiofrequency energy applications (4.1 ± 2.4 vs. 6.3 ± 3.5, P = 0.003) compared with the traditional group. One complete atrioventricular block and one left bundle branch block were seen in the traditional group. Over mean follow-up of 65 months, 89 (93.7%) patients in the FAP group and 81 (86.2%) patients in the traditional group remained free of recurrent VT off antiarrhythmic drugs (P = 0.157). CONCLUSION: Left posterior fascicular-ventricular tachycardia ablation utilizing FAP and traditional ablation approaches resulted in similar acute and long-term procedural outcomes. Serious His-Purkinje injury did occur infrequently during traditional ablation. The use of FAP ablation approach was associated with shorter procedure time and fewer radiofrequency energy applications, especially for non-inducible patients.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Humanos , Eletrocardiografia , Resultado do Tratamento , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/cirurgia , Bloqueio de Ramo , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos
17.
iScience ; 26(11): 108060, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37942015

RESUMO

Patients with coronary artery disease (CAD) at low residual inflammatory risk are often overlooked in research and practice. This study examined the associations between fourteen inflammatory indicators and all-cause mortality in 5,339 CAD patients with baseline high-sensitivity C-reactive protein (hsCRP) <2 mg/L who received percutaneous coronary intervention and statin and aspirin therapy. The median follow-up time was 2.1 years. Neutrophil-derived systemic inflammatory response index (SIRI) yielded the strongest and most robust association with all-cause mortality among all indicators. Lower hsCRP remained to be associated with a lower risk of all-cause mortality. A newly developed comprehensive inflammation score (CIS) showed better predictive performance than other indicators, which was validated by an independent external cohort. In conclusion, neutrophil-derived indicators, particularly SIRI, strongly predicted all-cause mortality independent of hsCRP in CAD patients at low residual inflammatory risk. CIS may help identify individuals with inflammation burdens that cannot be explained by hsCRP alone.

18.
ACS Appl Mater Interfaces ; 15(46): 53746-53754, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37920991

RESUMO

Excellent energy-absorbing structures have been highly sought after in engineering applications to improve devices and personal safety. The ideal energy absorption mechanism should exhibit characteristics such as lightweight, high energy absorption capacity, and efficient reusability. To address this demand, a novel three-dimensional (3D) chiral lattice structure with compression-twist coupling deformation is fabricated by combining the left and right chiral units. The proposed structure was fabricated in NiTi shape memory alloys (SMAs) by using laser powder bed fusion technology. The compression experiment result indicates that the shape recovery ratio is as high as 94% even when the compression strain is over 80%. Additionally, the platform strain reaches as high as 66%, offering high-level specific energy absorption, i.e., 213.02 J/g. The obtained results are of great significance for basic research and engineering applications of energy-absorbing structures with high deformation recovery ratios.

19.
Biosensors (Basel) ; 13(10)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37887123

RESUMO

This review focuses on electroencephalogram (EEG) acquisition and feedback technology and its core elements, including the composition and principles of the acquisition devices, a wide range of applications, and commonly used EEG signal classification algorithms. First, we describe the construction of EEG acquisition and feedback devices encompassing EEG electrodes, signal processing, and control and feedback systems, which collaborate to measure faint EEG signals from the scalp, convert them into interpretable data, and accomplish practical applications using control feedback systems. Subsequently, we examine the diverse applications of EEG acquisition and feedback across various domains. In the medical field, EEG signals are employed for epilepsy diagnosis, brain injury monitoring, and sleep disorder research. EEG acquisition has revealed associations between brain functionality, cognition, and emotions, providing essential insights for psychologists and neuroscientists. Brain-computer interface technology utilizes EEG signals for human-computer interaction, driving innovation in the medical, engineering, and rehabilitation domains. Finally, we introduce commonly used EEG signal classification algorithms. These classification tasks can identify different cognitive states, emotional states, brain disorders, and brain-computer interface control and promote further development and application of EEG technology. In conclusion, EEG acquisition technology can deepen the understanding of EEG signals while simultaneously promoting developments across multiple domains, such as medicine, science, and engineering.


Assuntos
Interfaces Cérebro-Computador , Epilepsia , Humanos , Retroalimentação , Eletroencefalografia , Epilepsia/diagnóstico , Emoções , Processamento de Sinais Assistido por Computador , Algoritmos
20.
Phys Chem Chem Phys ; 25(40): 27373-27379, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37791950

RESUMO

Three novel hexagonal Si-C-N structures, namely SiC3N3, SiC7N6, and SiC13N14, were constructed on the basis of the α-Si3N4 crystal structure. The stability of the three structures is demonstrated by analyzing their elastic constants and phonon dispersion spectra and by calculating their formation energies. The calculated band structures and partial densities of states suggest that the SiC3N3 and SiC7N6 structures possess hole conductivity. The electron orbital analyses indicate that the SiC3N3 and SiC7N6 crystals possess three-dimensional and one-dimensional conductivity, respectively. SiC13N14 is a semiconductor with a wide bandgap of 4.39 eV. Based on two different hardness models and indentation shear stress calculations, the Vickers hardness values of SiC3N3, SiC7N6, and SiC13N14 are estimated to be 28.04/28.45/16.18 GPa, 31.17/34.19/20.24 GPa, and 40.60/41.59/36.40 GPa. This result indicates that SiC3N3 and SiC7N6 are conductive hard materials while SiC13N14 is a quasi superhard material.

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