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BACKGROUND: Pulsed field ablation (PFA) is a novel, myocardial-selective, non-thermal ablation modality used to target cardiac arrhythmias. Although prompt EGM signal disappearance is observed immediately after PFA application in the pulmonary veins, whether this finding results in adequate transmural lesions is unknown. STUDY AIM: If application repetition and catheter-tissue contact impact on lesion formation during PFA. METHODS: A circular loop PFA catheter was used to deliver repeated energy applications with various levels of contact-force. A benchtop vegetal potato model and a beating heart ventricular myocardial model were utilized to evaluate the impact of application repetition, contact force, and catheter repositioning on contiguity and lesion depth. Lesion development occurred over 18 hours in the vegetal model and over 6 hours in the porcine model. RESULTS: Lesion formation was found to be dependent on application repetition and contact. In porcine ventricles, single and multiple stacked applications led to a lesion depth of 3.5 ± 0.7 mm and 4.4 ± 1.3 mm, respectively (p =0.002). Furthermore, the greater the catheter-tissue contact, the more contiguous and deeper the lesions in the vegetal model (1.0±0.9 mm with no contact Vs. 5.4±1.4 mm with 30 g of force; p=.0001). CONCLUSION: PFA delivered via a circular catheter showed that both repetition and catheter contact led independently to deeper lesion formation. These findings indicate that endpoints for effective PFA ablation are more related to PFA biophysics than mere EGM attenuation.
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Helicobacter pylori colonization of the human stomach is a strong risk factor for gastric cancer. To investigate H. pylori-induced gastric molecular alterations, we used a Mongolian gerbil model of gastric carcinogenesis. Histologic evaluation revealed varying levels of atrophic gastritis (a premalignant condition characterized by parietal and chief cell loss) in H. pylori-infected animals, and transcriptional profiling revealed a loss of markers for these cell types. We then assessed the spatial distribution and relative abundance of proteins in the gastric tissues using imaging mass spectrometry and liquid chromatography with tandem mass spectrometry. We detected striking differences in the protein content of corpus and antrum tissues. Four hundred ninety-two proteins were preferentially localized to the corpus in uninfected animals. The abundance of 91 of these proteins was reduced in H. pylori-infected corpus tissues exhibiting atrophic gastritis compared with infected corpus tissues exhibiting non-atrophic gastritis or uninfected corpus tissues; these included numerous proteins with metabolic functions. Fifty proteins localized to the corpus in uninfected animals were diffusely delocalized throughout the stomach in infected tissues with atrophic gastritis; these included numerous proteins with roles in protein processing. The corresponding alterations were not detected in animals infected with a H. pylori ∆cagT mutant (lacking Cag type IV secretion system activity). These results indicate that H. pylori can cause loss of proteins normally localized to the gastric corpus as well as diffuse delocalization of corpus-specific proteins, resulting in marked changes in the normal gastric molecular partitioning into distinct corpus and antrum regions.IMPORTANCEA normal stomach is organized into distinct regions known as the corpus and antrum, which have different functions, cell types, and gland architectures. Previous studies have primarily used histologic methods to differentiate these regions and detect H. pylori-induced alterations leading to stomach cancer. In this study, we investigated H. pylori-induced gastric molecular alterations in a Mongolian gerbil model of carcinogenesis. We report the detection of numerous proteins that are preferentially localized to the gastric corpus but not the antrum in a normal stomach. We show that stomachs with H. pylori-induced atrophic gastritis (a precancerous condition characterized by the loss of specialized cell types) exhibit marked changes in the abundance and localization of proteins normally localized to the gastric corpus. These results provide new insights into H. pylori-induced gastric molecular alterations that are associated with the development of stomach cancer.
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Gastrite Atrófica , Gastrite , Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Animais , Humanos , Gastrite Atrófica/induzido quimicamente , Neoplasias Gástricas/patologia , Gerbillinae , Mucosa Gástrica/patologia , Gastrite/patologia , Atrofia/patologia , Infecções por Helicobacter/complicações , Lesões Pré-Cancerosas/patologia , Carcinogênese/patologiaRESUMO
Introduction and objectives: Cryptococcus is a fungal pathogen, epidemiologically dominant in tropical and subtropical areas of Australia. With this clinical case report, we aim to acknowledge the incidence of pathogen in Victoria and solidify clinicians to in considering as a differential diagnosis with its different nature of presentations. Materials and methods: We identified five cases of pulmonary cryptococcus over a period of 10 months at Monash Medical Centre, Clayton, Victoria. Cases were retrospectively reviewed from onset of presentations through diagnosis and management. Identities and personal information of patients remained anonymous. Consents were obtained via electronic medical documentation. Results: In this case study, only one patient was immunosuppressed while others were immunocompetent. Number of cryptococcus gatti and neoformans was equally distributed in immunocompetent patients, while immunosuppressed patient had C.neoformans. Four out of five patients had respiratory symptoms and remaining patient (immunocompetent) had neurological complication despite absence of respiratory symptoms. As of radiological features, cavitating lesion was observed in immunosuppressed patient, while in immunocompetent ones, two had nodular feature, one had cavitating and other had endobronchial soft tissue density. Three patients achieved diagnosis confirmation by bronchial washings + BAL while two achieved by biopsy.
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BACKGROUND: Pulsed field ablation (PFA) has emerged as an alternative to radiofrequency ablation. However, data on focal point-by-point PFA are scarce. The aim of this study was to compare lesion durability and collateral damage between focally delivered unipolar/biphasic PFA versus radiofrequency in swine. METHODS: Eighteen swine were randomized to low-dose PFA, high-dose PFA, and radiofrequency using a multimodality generator. Radiofrequency delivered by market-available generator served as control group. A contact force-sensing catheter was used to focally deliver PFA/radiofrequency at the pulmonary veins and other predefined sites in the atria. Animals were remapped postprocedurally and 28 days postablation to test lesion durability followed by gross necroscopy and histology. RESULTS: All targeted sites were successfully ablated (contact force value, 13.9±4.1 g). Follow-up remapping showed persistent pulmonary vein isolation in all animals (100%) with lesion durability at nonpulmonary vein sites proven in most (98%). Regardless of the energy source used, the lesion size was similar across the study groups. Transmurality was achieved in 95% of targeted sites and 100% at pulmonary veins. On histology, PFA animals showed more mature scar formation than their radiofrequency counterpart without myocardial necrosis or inflammation. Finally, no sign of collateral damage was observed in any of the groups. CONCLUSIONS: In a randomized preclinical study, focally delivered unipolar/biphasic PFA guided by contact force values was associated with durable lesions on chronic remapping and with mature scar formation on histology without signs of collateral injury on necroscopy. Further studies are needed to investigate the long-term feasibility of this new approach to atrial fibrillation treatment.
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Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Ablação por Radiofrequência , Animais , Catéteres , Cicatriz , Suínos , Resultado do TratamentoRESUMO
AIMS: Intracardiac echocardiography (ICE) is a useful but operator-dependent tool for left atrial (LA) anatomical rendering during atrial fibrillation (AF) ablation. The CARTOSOUND FAM Module, a new deep learning (DL) imaging algorithm, has the potential to overcome this limitation. This study aims to evaluate feasibility of the algorithm compared to cardiac computed tomography (CT) in patients undergoing AF ablation. METHODS AND RESULTS: In 28 patients undergoing AF ablation, baseline patient information was recorded, and three-dimensional (3D) shells of LA body and anatomical structures [LA appendage/left superior pulmonary vein/left inferior pulmonary vein/right superior pulmonary vein/right inferior pulmonary vein (RIPV)] were reconstructed using the DL algorithm. The selected ultrasound frames were gated to end-expiration and max LA volume. Ostial diameters of these structures and carina-to-carina distance between left and right pulmonary veins were measured and compared with CT measurements. Anatomical accuracy of the DL algorithm was evaluated by three independent electrophysiologists using a three-anchor scale for LA anatomical structures and a five-anchor scale for LA body. Ablation-related characteristics were summarized. The algorithm generated 3D reconstruction of LA anatomies, and two-dimensional contours overlaid on ultrasound input frames. Average calculation time for LA reconstruction was 65â s. Mean ostial diameters and carina-to-carina distance were all comparable to CT without statistical significance. Ostial diameters and carina-to-carina distance also showed moderate to high correlation (r = 0.52-0.75) except for RIPV (r = 0.20). Qualitative ratings showed good agreement without between-rater differences. Average procedure time was 143.7 ± 43.7â min, with average radiofrequency time 31.6 ± 10.2â min. All patients achieved ablation success, and no immediate complications were observed. CONCLUSION: DL algorithm integration with ICE demonstrated considerable accuracy compared to CT and qualitative physician assessment. The feasibility of ICE with this algorithm can potentially further streamline AF ablation workflow.
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Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Inteligência Artificial , Estudos de Viabilidade , Ecocardiografia/métodos , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/cirurgia , Imageamento Tridimensional/métodos , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Algoritmos , Ablação por Cateter/métodosRESUMO
Hepatitis C (HCV) infection elimination in low- and middle-income countries requires decentralised HCV services to increase testing and linkage to care. The CT2 Study investigated patients' views of access to and acceptance of two community-based HCV care models in Myanmar using a mixed-methods approach. Point-of-care HCV testing and general practitioner-initiated HCV treatment were provided at two community clinics in Yangon, Myanmar-the Burnet Institute's (BI) clinic focused on people who inject drugs (PWID), and the Myanmar Liver Foundation's (MLF) clinic focused on people with liver-related diseases. Study staff administered quantitative questionnaires to 633 participants receiving anti-HCV antibody testing. Purposive sampling was used to recruit 29 participants receiving direct-acting antiviral treatment for qualitative interviews. Among participants completing quantitative questionnaires, almost all reported the clinic location was convenient (447/463, 97%), waiting time was acceptable (455/463, 98%), and HCV antibody and RNA testing methods were acceptable (617/632, 98% and 592/605, 97% respectively). Nearly all participants were satisfied with their clinic's services (444/463, 96%) and preferred same-day test results (589/632, 93%). BI clinic participants were more confident that they understood HCV antibody and RNA results; MLF clinic participants were more comfortable disclosing their risk behaviour to staff and had slightly higher satisfaction with the overall care, privacy and secure storage of their information. In qualitative interviews, participants reported that flexible appointment scheduling, short wait times and rapid return of results increased the clinic's accessibility. The simplified point-of-care testing and treatment procedures and supportive healthcare providers contributed to participants' acceptance of the HCV care model. This decentralised community-based HCV testing and treatment model was highly accessible and acceptable to CT2 participants. Prioritizing patient-centred care, rapid provision of results, flexible appointments and convenient clinic locations can promote accessible and acceptable services which may in turn help accelerate progress in reaching HCV elimination targets.
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Idiopathic ventricular arrhythmias (VA), particularly left ventricular outflow tract (LVOT) VA accounts for up to 10% of all VAs referred for ablative therapy. In addition to being infrequent, its intricate anatomy and its pathophysiology make catheter ablation (CA) of these arrhythmias a challenge even for experts. In this scenario, detailed right ventricular outflow tract as well as LVOT electroanatomic mapping including epicardial mapping are essential. In this article, we will emphasize our approach toward the CA technique used for LVOT VA, particularly IVS and/or LVS VA originating from intramural foci, along with its acute and long-term efficacy and safety.
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Ablação por Cateter , Taquicardia Ventricular , Humanos , Taquicardia Ventricular/cirurgia , Ventrículos do Coração/cirurgia , Arritmias Cardíacas , Mapeamento Epicárdico , Ablação por Cateter/métodos , Eletrocardiografia , Resultado do TratamentoRESUMO
Prolonged use of fluoroscopy during catheter ablation (CA) of arrhythmias is associated with a significant exposure to ionizing radiation and risk of orthopedic injuries given the need for heavy protective equipment. CA of ventricular arrhythmias (VAs) arising from the left ventricular (LV) summit is challenging, requiring a vast knowledge of the intricate cardiac anatomy of this area and careful imaging delineation of the different anatomical structures, which is frequently performed using fluoroscopic guidance. Certain techniques, including pericardial mapping and ablation, use of intracoronary wires, and mapping and ablation inside the coronary venous system have been proposed, further prolonging fluoroscopy time. Fluoroless CA procedures are feasible with currently available technology and appear to have similar safety and efficacy outcomes compared with conventional techniques. To successfully perform fluoroless CA of LV summit arrhythmias, it is important to be fully acquainted with intracardiac echocardiography (ICE) imaging and electroanatomic mapping (EAM). We will describe our approach to perform fluoroless CA in LV summit VAs.
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Arritmias Cardíacas , Ablação por Cateter , Humanos , Resultado do Tratamento , Arritmias Cardíacas/diagnóstico por imagem , Arritmias Cardíacas/cirurgia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/cirurgia , Coração , Ablação por Cateter/métodosRESUMO
INTRODUCTION: Complex atrial tachyarrhythmias (CATs) are commonly observed in patients with prior catheter ablation or cardiac surgery. These arrhythmias are challenging to map and ablate. Historically, entrainment mapping was utilized to characterize CAT. With the advent of high-definition mapping (HDM), full visualization of the CAT circuit is possible which may obviate the need for entrainment mapping. METHODS: We sought to investigate the outcomes of catheter ablation of CAT guided only by HDM. Consecutive patients who underwent CAT ablation from 2017 to 2021 were included in our study (excluding right atrial tachyarrhythmias). Patients were sorted by the type of mapping performed. Group I consisted of patients where HDM alone was utilized with no attempt of entrainment. Group II consisted of patients where both entrainment and HDM were utilized. RESULTS: A total of 67 patients were included in our study, with 40 patients in HDM group (I) and 27 patients in entrainment group (II). No statistically significant difference regarding 1-year freedom from atrial arrhythmias was found between the two groups (80% vs 77.8%, p = 0.819). Four CATs were terminated by entrainment during procedure versus none in the HDM-only group (p = 0.011). CONCLUSIONS: CAT ablation with HDM alone yielded similar 1-year freedom from atrial arrhythmias compared to ablation with HDM and entrainment. Entrainment combined with HDM was associated with higher undesired CAT interruption rate. Further validation is needed with randomized control trials.
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Fibrilação Atrial , Ablação por Cateter , Humanos , Fibrilação Atrial/cirurgia , Resultado do Tratamento , Taquicardia/cirurgia , Átrios do Coração/cirurgia , Ablação por Cateter/métodosRESUMO
BACKGROUND: Adverse structural and electrical remodeling underlie persistent atrial fibrillation (PersAF). Restoration of sinus rhythm (SR) prior to ablation in PersAF may improve the underlying substrate, thus improving arrhythmia outcomes. The aim of this study was to evaluate if the presence of SR at time of ablation is associated with improved long-term arrhythmia outcomes of a limited catheter ablation (CA) strategy in PersAF. METHODS: Patients with PersAF undergoing pulmonary vein isolation at our institution from 2014-2018 were included. We compared patients who presented for ablation in SR (by cardioversion and/or antiarrhythmic drugs [AADs]) to those who presented in AF. Primary outcome of interest was freedom from atrial arrhythmias (AAs) on or off AADs at 1 year after single ablation. Secondary outcomes included freedom from AAs on or off AADs overall, freedom from AAs off AADs at 1 year, and time to recurrent AF. RESULTS: Five hundred seventeen patients were included (322 presented in AF, 195 SR). The primary outcome was higher in those who presented for CA in SR as compared to AF (85.6% vs. 77.0%, p = 0.017). Freedom from AAs off AAD at 12 months was also higher in those presenting in SR (59.0% vs. 44.4%; p = 0.001) and time to recurrent AF was longer (p = 0.008). Presence of SR at CA was independently associated with the primary outcome at 12 months (OR 1.77; 95% CI 1.08-2.90) and overall (OR 1.89; 95% CI 1.26-2.82). CONCLUSIONS: Presence of SR at time of ablation is associated with improved long-term arrhythmia outcomes of limited CA in PersAF.
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Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Veias Pulmonares/cirurgia , Resultado do Tratamento , Antiarrítmicos/uso terapêutico , Fatores de Tempo , Ablação por Cateter/efeitos adversos , RecidivaRESUMO
INTRODUCTION: Atrial fibrillation (AF) and premature ventricular complexes (PVC) are common arrhythmias. We aimed to investigate AF prevalence in patients with PVC and its impact on PVC ablation outcomes. METHODS: Consecutive patients undergoing PVC ablation at a single institution between 2016 and 2019 were included and prospectively followed for 2 years. Patients with severe valvular heart disease, hyperthyroidism, malignancy, alcohol use disorder and advanced renal/hepatic diseases were excluded. Twelve-lead electrocardiograms were used to diagnose AF and assess PVC morphology. All PVCs were targeted for ablation using 4-mm irrigated-tip catheters at standardized radiofrequency power guided by 3-D mapping and intracardiac echocardiography. Patients were followed with remote monitoring, device interrogations and office visits every 6 months for 2 years. Detection of any PVCs in follow-up was considered as recurrence. RESULTS: A total of 394 patients underwent PVC ablation and 96 (24%) had concurrent AF. Patients with PVC and AF were significantly older (68.2 ± 10.8 vs. 58.3 ± 15.8 years, p < .001), had lower LV ejection fraction (43.3 ± 13.3% vs. 49.6 ± 12.4%, p < .001), higher CHA2 DS2 -VASc (2.8 ± 1.3 vs. 2.0 ± 1.3, p < .001) than those without. PVCs with ≥2 morphologies were detected in 60.4% and 13.7% patients with vs without AF (p < .001). At 2-year follow-up, PVC recurrence rate was significantly higher in patients with vs without AF (17.7% vs. 9.4%, p = .02). CONCLUSION: AF was documented in 1/4 of patients undergoing PVC ablation and was associated with lower procedural success at long-term follow-up. This was likely attributed to older age, worse LV function and higher prevalence of multiple PVC morphologies in patients with concurrent AF.
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Fibrilação Atrial , Ablação por Cateter , Complexos Ventriculares Prematuros , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/cirurgia , Resultado do Tratamento , Prevalência , Volume Sistólico , Complexos Ventriculares Prematuros/diagnóstico , Complexos Ventriculares Prematuros/epidemiologia , Complexos Ventriculares Prematuros/cirurgia , Ablação por Cateter/efeitos adversosRESUMO
Objectives: This study aimed to assess the perception of PBL among Japanese medical students. Methods: Learning effects and challenges of PBL from the students' viewpoint were assessed with an exploratory sequential mixed method. Focus group discussions followed by thematic analysis were conducted with 27 students and residents. Then a questionnaire survey was carried out. A total of 119 out of 258 students (46.1%) responded. The results from 24 questions were analyzed with a residual analysis. Results: Thematic analysis extracted 14 themes from four discussion topics. The participants in focus group discussion regarded the PBL program as a better learning method than lectures. But some key phrases on the challenge of social interaction, including reluctance to actively discuss and collaborate with unfamiliar peers, were found. The questionnaire survey revealed a significantly lower adjusted standardized residual (ASR) for the positive response in five of six questions in the category of social interaction; improvement of communication skills (ASR = -3.303, n = 118, p < .001), enhancement of responsibility at group discussions (ASR = -2.078, n = 119, p = .038), building social networking (ASR = -3.006, n = 119, p = .003), becoming to sympathize with patients (ASR = -2.449, n = 119, p = .014) and understanding social aspects of clinical practice (ASR = -5.790, n = 119, p < .001). Conclusion: The Japanese medical students perceived PBL as an effective learning strategy. However, they had a problem with social interactions.
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Aprendizagem Baseada em Problemas , Estudantes de Medicina , Humanos , Aprendizagem Baseada em Problemas/métodos , Faculdades de Medicina , População do Leste Asiático , PercepçãoRESUMO
BACKGROUND: Although efficacious, catheter ablation (CA) of ventricular arrhythmias (VAs) originating from left ventricular (LV) papillary muscles (PAPs) has the potential to affect mitral valve (MV) function. OBJECTIVES: The aim of this study was to determine whether lesions delivered during CA of VAs from LV PAPs affected MV function. METHODS: Consecutive patients undergoing CA of LV PAP VAs from January 2015 to December 2020 in whom both preprocedural and postprocedural transthoracic echocardiography was performed were included. Radiofrequency ablation was performed with an irrigated-tip catheter with or without contact force sensing and intracardiac echocardiographic guidance. The PAPs were delineated into segments: tip, body, and base. Pre- and post-CA transthoracic echocardiograms were reviewed to assess MV regurgitation, which was graded 0 (none), 1 (mild), 2 (moderate), or 3 (severe). A change of ≥2 grades from baseline was considered significant. RESULTS: A total of 103 patients (mean age 63 ± 15 years, 78% men) were included. VAs were ablated from the anterolateral PAP in 35% (n = 36), posteromedial PAP in 55% (n = 57), and both PAPs in 10% (n = 10). Lesion distribution was as follows: PAP tip in 52 (50%), PAP base in 34 (33%), PAP body in 13 (13%), and entire PAP in 4 (4%). The mean number of lesions delivered was 16 ± 13 (median 14). Of 103 patients, 102 (99%) showed no change in MV function. CONCLUSIONS: Using intracardiac echocardiographic guidance, lesions can be safely delivered on various aspects of this structure without adverse impact on MV function.
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Ablação por Cateter , Taquicardia Ventricular , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Músculos Papilares/diagnóstico por imagem , Músculos Papilares/cirurgia , Taquicardia Ventricular/cirurgia , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Arritmias Cardíacas , Ablação por Cateter/efeitos adversosRESUMO
To evaluate potential effects of gastric inflammation on Helicobacter pylori diversification and evolution within the stomach, we experimentally infected Mongolian gerbils with an H. pylori strain in which Cag type IV secretion system (T4SS) activity is controlled by a TetR/tetO system. Gerbils infected with H. pylori under conditions in which Cag T4SS activity was derepressed had significantly higher levels of gastric inflammation than gerbils infected under conditions with repressed Cag T4SS activity. Mutations in the 5' untranslated region (UTR) of katA (encoding catalase) were detected in strains cultured from 8 of the 17 gerbils infected with Cag T4SS-active H. pylori and none of the strains from 17 gerbils infected with Cag T4SS-inactive H. pylori. Catalase enzymatic activity, steady-state katA transcript levels, and katA transcript stability were increased in strains with these single nucleotide polymorphisms (SNPs) compared to strains in which these SNPs were absent. Moreover, strains harboring these SNPs exhibited increased resistance to bactericidal effects of hydrogen peroxide, compared to control strains. Experimental introduction of the SNPs into the wild-type katA 5' UTR resulted in increased katA transcript stability, increased katA steady-state levels, and increased catalase enzymatic activity. Based on site-directed mutagenesis and modeling of RNA structure, increased katA transcript levels were correlated with higher predicted thermal stability of the katA 5' UTR secondary structure. These data suggest that high levels of gastric inflammation positively select for H. pylori strains producing increased levels of catalase, which may confer survival advantages to the bacteria in an inflammatory gastric environment.
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Gastrite , Infecções por Helicobacter , Helicobacter pylori , Regiões 5' não Traduzidas/genética , Animais , Catalase/genética , Mucosa Gástrica/microbiologia , Gastrite/microbiologia , Gerbillinae/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Inflamação/genética , MutaçãoRESUMO
OBJECTIVES: This study sought to explore whether prolonged duration (PD) radiofrequency ablation (RFA) from adjacent endocardial locations can improve catheter ablation (CA) outcomes of left ventricular summit (LVS) ventricular arrhythmias (Vas). BACKGROUND: CA of VAs originating from the LVS region can be challenging. METHODS: Patients undergoing CA of LVS VAs from January 1, 2015, to December 31, 2019, were included. Standard RFA approach involved incremental power titration (20-45 W) over 60-120 seconds with irrigated tip catheter to achieve 10%-12% impedance drop. Prolonged duration RFA involved similar power titration; however, lesion application was extended beyond 120 seconds (maximum 5 minutes). Lesions were confined to lowest aspect of aortic cusps and/or subvalvular LV outflow tract region (≤0.5 cm from the valve). Procedural success was defined as suppression of VA ≥30 minutes postablation and clinical success as no arrhythmia symptoms on follow-up and >80% reduction of VA burden on postprocedure monitor. RESULTS: This study included 102 patients (60±14 years old, 62% male): standard RFA in 80 and PD RFA in 38. Procedural success was achieved in 54 patients with standard and 32 patients with PD RFA (68% vs 84%; P = 0.05). Short-term clinical success was achieved in 48 patients (60%) with standard and 30 patients (79%) with PD RFA (P = 0.04). Two pericardial effusions occurred (1 in each group) and no steam pops were noted. Patients in whom standard RFA was successful were more likely to have R/S ratio >1 or absence of qS in lead I (odds ratio: 3.35; 95% CI: 1.20-9.35; P = 0.03). CONCLUSIONS: Prolonged duration RFA from adjacent endocardial locations is a safe and effective technique for successfully targeting challenging LVS VAs that fail standard RFA.
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Ablação por Cateter , Ventrículos do Coração , Idoso , Arritmias Cardíacas/cirurgia , Ablação por Cateter/métodos , Endocárdio/cirurgia , Feminino , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND: The right ventricle (RV) is uncommonly implicated in postinfarction ventricular tachycardia (VT). The prevalence and features of the RV substrate participating in postinfarction VT are undefined. OBJECTIVES: The purpose of this study was to characterize critical right ventricular substrate (CRVS) involvement in patients with postinfarction VT. METHODS: We retrospectively reviewed 1279 patients with postinfarction VT undergoing catheter ablation at our center from January 2000 through May 2020. Cases with CRVS defined by conclusive demonstration of participation in VT with activation, entrainment, and/or pacemapping during sinus rhythm were identified. RESULTS: CRVS was identified in 27 of 1279 patients (2.1%): age 65 ± 13 years, 96% male, median left ventricular (LV) ejection fraction 25%, and 93% with left bundle branch block (LBBB) morphology VT. CRVS was identified by RV activation and/or entrainment mapping (n = 19) or by the presence of low-voltage abnormal electrograms with excellent pacemap for the targeted VT and noninducibility after ablation (n = 8). VT termination during RV ablation occurred in 15 patients. After median follow-up of 20 months (interquartile range 9-53 months) and median of 2 procedures (interquartile range 1-3), 22 of 27 patients (80%) had no VT recurrence and 11 (41%) died. CONCLUSION: The RV contains critical substrate elements of postinfarction VT in at least 2.1% of cases. RV mapping should be considered in cases in which LV mapping fails to demonstrate adequate targets, particularly in patients with LBBB morphology VT.
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Ablação por Cateter , Taquicardia Ventricular , Idoso , Bloqueio de Ramo , Feminino , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taquicardia Ventricular/epidemiologia , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/cirurgia , Resultado do TratamentoRESUMO
Traditionally, the genus Rhinopithecus (Milne-Edwards, 1872, Primates, Colobinae) included four allopatric species, restricted in their distributions to China and Vietnam. In 2010, a fifth species, the black snub-nosed monkey (Rhinopithecus strykeri) was discovered in the Gaoligong Mountains located on the border between China and Myanmar. Despite the remoteness, complex mountainous terrain, dense fog, and armed conflict that characterizes this region, over this past decade Chinese and Myanmar scientists have begun to collect quantitative data on the ecology, behavior and conservation requirements of R. strykeri. In this article, we review the existing data and present new information on the life history, ecology, and population size of R. strykeri. We discuss these data in the context of past and current conservation challenges faced by R. strykeri, and propose a series of both short-term and long-term management actions to ensure the survival of this Critically Endangered primate species. Specifically, we recommend that the governments and stakeholders in China and Myanmar formulate a transboundary conservation agreement that includes a consensus on bilateral exchange mechanisms, scientific research and monitoring goals, local community development, cooperation to prevent the hunting of endangered species and cross-border forest fires. These actions will contribute to the long-term conservation and survival of this Critically Endangered species.
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Colobinae , Presbytini , Animais , Aniversários e Eventos Especiais , China , Espécies em Perigo de Extinção , Densidade DemográficaRESUMO
We review the current data on epidemiology, the clinical significance, the pathophysiologic mechanisms, and the treatment of VAs in the setting of COVID-19. VAs prevail in 0.15% to 8% of hospitalized patients, but only sustained and rapid tachyarrhythmias are purportedly associated with a significant increase in mortality. Multiple factors can elicit VAs, which are ultimately deemed to be a marker of severe systemic disease rather than a distinct cardiac condition. Even though the electrophysiologist plays a determinant role in the secondary prevention of VAs, a multidisciplinary approach is indispensable for primary prophylaxis and acute management.
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COVID-19 , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/terapia , COVID-19/epidemiologia , Humanos , Prevalência , SARS-CoV-2 , TaquicardiaRESUMO
Numerous systemic manifestations, including cardiac involvement in the form of myocardial infarction, myocarditis, and electrocardiographic changes, have been associated with COVID-19..In this review, the authors describe the electrocardiographic features that have been reported to date in patients affected by this disease and their possible underlying mechanisms.