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Letteratura scientifica selezionata sul tema "Arrhythmia"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 29 luglio 2024

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Articoli di riviste sul tema "Arrhythmia"

Epifanio, Hindalis Ballesteros, Marcelo Katz, Melania Aparecida Borges, Alessandra da Graça Corrêa, Fátima Dumas Cintra, Rodrigo Leandro Grinberg, Ana Cristina Pinotti Pedro Ludovice, Bruno Pereira Valdigem, Nilton José Carneiro da Silva e Guilherme Fenelon. "The use of external event monitoring (web-loop) in the elucidation of symptoms associated with arrhythmias in a general population". Einstein (São Paulo) 12, n. 3 (settembre 2014): 295–99. http://dx.doi.org/10.1590/s1679-45082014ao2939.

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Objective To correlate arrhythmic symptoms with the presence of significant arrhythmias through the external event monitoring (web-loop). Methods Between January and December 2011, the web-loop was connected to 112 patients (46% of them were women, mean age 52±21 years old). Specific arrhythmic symptoms were defined as palpitations, pre-syncope and syncope observed during the monitoring. Supraventricular tachycardia, atrial flutter or fibrillation, ventricular tachycardia, pauses greater than 2 seconds or advanced atrioventricular block were classified as significant arrhythmia. The association between symptoms and significant arrhythmias were analyzed. Results The web-loop recorded arrhythmic symptoms in 74 (66%) patients. Of these, in only 14 (19%) patients the association between symptoms and significant cardiac arrhythmia was detected. Moreover, significant arrhythmia was found in 11 (9.8%) asymptomatic patients. There was no association between presence of major symptoms and significant cardiac arrhythmia (OR=0.57, CI95%: 0.21-1.57; p=0.23). Conclusion We found no association between major symptoms and significant cardiac arrhythmia in patients submitted to event recorder monitoring. Event loop recorder was useful to elucidate cases of palpitations and syncope in symptomatic patients.

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Sridhar, Anuradha, Alessandro Giamberti, Sara Foresti, Riccardo Cappato, Carlos Rubio-Iglesias García, Nerea Delgado Cabrera, Angelo Micheletti et al. "Fontan conversion with concomitant arrhythmia surgery for the failing atriopulmonary connections: mid-term results from a single centre". Cardiology in the Young 21, n. 6 (27 maggio 2011): 665–69. http://dx.doi.org/10.1017/s1047951111000643.

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AbstractObjectivesClassical Atriopulmonary Fontan connections tend to fail in the long term due to progressive anastomotic site obstruction, right atrial enlargement, and refractory atrial arrhythmias. Conversion to total cavopulmonary connection with concomitant arrhythmia surgery is a promising treatment but optimal timing of the procedure remains controversial.MethodsBetween the years 2002 and 2009, 15 patients with a median age of 26.2 (12–43) years underwent Fontan conversion operation with concomitant arrhythmia surgery. All were symptomatic and 14 out of the 15 patients had refractory arrhythmias. The duration of pre-operative arrhythmia and the outcome of surgery were correlated to study the impact of delay in surgical intervention on post-operative survival and arrhythmia control.ResultsThere were two patients who died in the early post-operative period (13.3%). At the mid-term follow-up, 53 (20–86) months, late atrial arrhythmias had recurred in two of the 13 surviving patients (15.30%) and one patient developed late sinus node dysfunction. The need for anti-arrhythmic drugs decreased considerably from 93.5% to 15.3% on mid-term follow-up. There was no late death or need for cardiac transplantation. The duration of arrhythmia before surgery was prolonged for more than 10 years in patients who died as well as in those who had complications like late recurrence of arrhythmias, dependence on anti-arrhythmic medications, and worsening of ventricular dysfunction.ConclusionsFontan conversion is a well-established treatment option for salvaging the failing atriopulmonary connections. Concomitant arrhythmia surgery effectively resolves the refractory atrial arrhythmias and improves survival, but we need to optimise the timing of Fontan conversion to improve the long-term outcome.

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Akhmedov, V. A., M. A. Livzan e O. V. Gaus. "COVID-19 and arrhythmias - is there a relationship?" South Russian Journal of Therapeutic Practice 3, n. 3 (1 settembre 2022): 17–24. http://dx.doi.org/10.21886/2712-8156-2022-3-3-17-24.

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COVID-19 infection is associated with many different systemic complications. Among these, cardiovascular system complications are particularly important as these are associated with significant mortality. There are many different subgroups of cardiovascular complications, with arrhythmias being one of them. Arrhythmias are especially important as there are a substantial percentage of patients who have arrhythmia after a COVID-19 infection, and these patients are seen with an increased mortality rate. Arrhythmias in COVID-19 patients are associated with inflammation, electrolyte abnormalities, hypoxia, myocardial ischemia, cytokines, pro-arrhythmic or QT-prolonging medications, and underlying heart conditions such as severe congestive heart failure, inherited arrhythmia syndromes, or congenital heart conditions. In addition, arrhythmias and cardiac arrests are most prevalent in the critically ill intensive care unit COVID-19 patient population. This review of PubMed/MedLine articled presents an overview of the association between COVID-19 and arrhythmias by detailing possible pathophysiological mechanisms, existing knowledge of pro-arrhythmic factors, and results from studies in adult COVID-19 populations.

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Gasperetti, Alessio, Cynthia A. James, Liang Chen, Niklas Schenker, Michela Casella, Shinwan Kany, Shibu Mathew et al. "Efficacy of Catheter Ablation for Atrial Arrhythmias in Patients with Arrhythmogenic Right Ventricular Cardiomyopathy—A Multicenter Study". Journal of Clinical Medicine 10, n. 21 (26 ottobre 2021): 4962. http://dx.doi.org/10.3390/jcm10214962.

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Background: Atrial arrhythmias are present in up to 20% of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). Catheter ablation (CA) is an effective treatment for atrial arrhythmias in the general population. Data regarding CA for atrial arrhythmias in ARVC are scarce. Objective: To assess the safety and efficacy of CA for atrial arrhythmias in patients with ARVC. Methods: In this international collaborative effort, all patients with a definite diagnosis of ARVC undergoing CA for atrial fibrillation (AF), focal atrial tachycardia (AT), or cavotricuspid isthmus (CTI)-dependent atrial flutter (AFl) were extracted from twelve ARVC registries. Demographic, periprocedural, and long-term arrhythmic outcome data were collected. Results: Thirty-seven patients were enrolled in the study (age 50.2 ± 16.6 years, male 84%, CHA2DS2VASc 1 (1,2), HAS-BLED 0 (0–2)). The arrhythmia leading to CA was AF in 23 (62%), focal left AT in 5 (14%), and CTI-dependent AFl in 9 (24%). Acute procedural success was achieved in all procedures but one (n = 1 focal left AT; 97% acute success). The median follow-up period was 27 (13–67) months, and 96%, 74%, and 61% of patients undergoing AF ablation were free from any atrial arrhythmia recurrence after a single procedure at 6 months, 12 months, and last follow-up, respectively. After focal AT ablation, freedom from atrial arrhythmia recurrence was 80%, 80%, and 60% at 6 months, 12 months, and last follow-up, respectively. All patients undergoing CTI ablation were free from atrial arrhythmia recurrences at 6 months, with 89% single-procedural arrhythmic freedom at last follow-up. One major complication (2.7%; PV stenosis requiring PV stenting) occurred. Conclusions: CA is safe and effective in managing atrial arrhythmias in patients with ARVC, with success rates comparable to the general population.

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Poeppel, T. D., M. Reinhardt, E. G. Vester, M. Yong, J. Mau, B. E. Strauer, H. Vosberg, H. W. Müller e B. J. Krause. "Myocardial perfusion/metabolism mismatch and ventricular arrhythmias in the chronic post infarction state". Nuklearmedizin 44, n. 03 (2005): 69–75. http://dx.doi.org/10.1055/s-0038-1625688.

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Summary Aim: Ventricular arrhythmias have been shown to originate in the myocardial peri-infarct region due to irregular heterotopic conduction. Hypoperfused but viable myocardium is often localised in those areas and may be involved in the pathogenesis of arrhythmias. We tested the hypothesis that these myocardial perfusion/metabolism mismatches (MM) are significantly associated with ventricular arrhythmias in the chronic post infarction state. Patients, methods: 47 post infarction patients were included in the study. 33 suffered from ventricular arrhythmia whereas 14 did not. All patients underwent 99mTc tetrofosmin SPECT and 18F-FDG PET. A region-of-interest(ROI)-analysis was used to assess viable myocardium based on predefined MM-criteria. Univariate analyses as well as a logistic regression model for the multivariate analysis were carried out. Results: 94% of the arrhythmic patients displayed at least one MM-segment as compared to 64% of the non-arrhythmic patients. MMsegments and arrhythmia showed a statistically significant relation (p = 0.018). The logistic regression model predicted the occurrence or absence of arrhythmia in 85% of all cases. Multivariate analysis gave consistent results, after adjusting for symptomatic chronic heart failure (CHF), aneurysms and age. Conclusion: Our results support the hypothesis that hypoperfused but viable myocardium represents an arrhythmogenic substrate and is a relevant risk factor for developing ventricular arrhythmias following myocardial infarction. Therefore, the detection of MM-segments allows the identification of patients with a higher risk for future cardiac events.

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CHIU, CHUANG-CHIEN, TONG-HONG LIN e BEN-YI LIAU. "USING CORRELATION COEFFICIENT IN ECG WAVEFORM FOR ARRHYTHMIA DETECTION". Biomedical Engineering: Applications, Basis and Communications 17, n. 03 (25 giugno 2005): 147–52. http://dx.doi.org/10.4015/s1016237205000238.

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Arrhythmia is one kind of diseases that gives rise to the death and possibly forms the immedicable danger. The most common cardiac arrhythmia is the ventricular premature beat. The main purpose of this study is to develop an efficient arrhythmia detection algorithm based on the morphology characteristics of arrhythmias using correlation coefficient in ECG signal. Subjects for experiments included normal subjects, patients with atrial premature contraction (APC), and patients with ventricular premature contraction (PVC). So and Chan's algorithm was used to find the locations of QRS complexes. When the QRS complexes were detected, the correlation coefficient and RR-interval were utilized to calculate the similarity of arrhythmias. The algorithm was tested using MIT-BIH arrhythmia database and every QRS complex was classified in the database. The total number of test data was 538, 9 and 24 for normal beats, APCs and PVCs, respectively. The results are presented in terms of, performance, positive predication and sensitivity. High overall performance (99.3%) for the classification of the different categories of arrhythmic beats was achieved. The positive prediction results of the system reach 99.44%, 100% and 95.35% for normal beats, APCs and PVCs, respectively. The sensitivity results of the system are 99.81%, 81.82% and 95.83% for normal beats, APCs and PVCs, respectively. Results revealed that the system is accurate and efficient to classify arrhythmias resulted from APC or PVC. The proposed arrhythmia detection algorithm is therefore helpful to the clinical diagnosis.

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van Bavel, Joanne J. A., Henriëtte D. M. Beekman, Agnieszka Smoczyńska, Marcel A. G. van der Heyden e Marc A. Vos. "IKs Activator ML277 Mildly Affects Repolarization and Arrhythmic Outcome in the CAVB Dog Model". Biomedicines 11, n. 4 (11 aprile 2023): 1147. http://dx.doi.org/10.3390/biomedicines11041147.

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Long QT syndrome type 1 with affected IKs is associated with a high risk for developing Torsade de Pointes (TdP) arrhythmias and eventually sudden cardiac death. Therefore, it is of high interest to explore drugs that target IKs as antiarrhythmics. We examined the antiarrhythmic effect of IKs channel activator ML277 in the chronic atrioventricular block (CAVB) dog model. TdP arrhythmia sensitivity was tested in anesthetized mongrel dogs (n = 7) with CAVB in series: (1) induction experiment at 4 ± 2 weeks CAVB: TdP arrhythmias were induced with our standardized protocol using dofetilide (0.025 mg/kg), and (2) prevention experiment at 10 ± 2 weeks CAVB: the antiarrhythmic effect of ML277 (0.6–1.0 mg/kg) was tested by infusion for 5 min preceding dofetilide. ML277: (1) temporarily prevented repolarization prolongation induced by dofetilide (QTc: 538 ± 65 ms at induction vs. 393 ± 18 ms at prevention, p < 0.05), (2) delayed the occurrence of the first arrhythmic event upon dofetilide (from 129 ± 28 s to 180 ± 51 s, p < 0.05), and (3) decreased the arrhythmic outcome with a significant reduction in the number of TdP arrhythmias, TdP score, arrhythmia score and total arrhythmic events (from 669 ± 132 to 401 ± 228, p < 0.05). IKs channel activation by ML277 temporarily suppressed QT interval prolongation, delayed the occurrence of the first arrhythmic event and reduced the arrhythmic outcome in the CAVB dog model.

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Baghel, Anita, Manoj Kumar, J. P. Soni, Mudit Agarwal e Ravi Kumar. "Experience with Holter monitoring for evaluation of infant arrhythmia". International Journal of Contemporary Pediatrics 6, n. 3 (30 aprile 2019): 1362. http://dx.doi.org/10.18203/2349-3291.ijcp20192044.

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Background: Arrhythmia is defined as abnormal heart rates. Sometimes they are intermittent and difficult to diagnose on routine ECG. Neonatologist and Pediatrician needs to rapidly establish accurate diagnosis and management for infants suspected to have arrhythmia. Hence Holter monitoring of the infants presenting with symptoms suggestive of arrhythmia is necessary as it provides a continuous record of heart’s electrical activity. The aim of this paper is to find out the role of continuous ambulatory electrocardiographic monitoring in daily clinical practice of Pediatrics.Methods: All infants including neonates, either inborn or brought to the paediatric emergency with risk factors, between January 2016 to January 2018, were included in this prospectively study. Evaluation including chest X-ray, standard 12-lead electrocardiography, 24 hours continuous ECG monitoring using Mortara holter, echocardiography, biochemical and haematological analysis.Results: A total of 73 babies were enrolled in present study. In this study arrhythmia was found in 29 (39.72%) new-borns. The most common arrhythmia observed was supraventricular tachycardia (SVT) (41.3%). Other arrhythmia observed were ventricular tachycardia (VT), AV block (34.4%), atria premature beats (3.4%) and ventricular premature beats (6.89%), tachy-bradyarrhythmia (3.4%) and junctional rhythm (3.4%). Of 29 arrhythmia patients four were diagnosed solely by Holter monitoring. None of the babies had long QT syndrome on Holter monitoring.Conclusions: Cardiac arrhythmias are important causes of infant morbidity, and mortality if undiagnosed and untreated. It is important for the neonatologist and paediatrician to be aware of these of arrhythmias and the various diagnostic modalities available for them. A Holter electrocardiogram may be of value in identification of these transient arrhythmic events.

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Gauvrit, Sébastien, Jaclyn Bossaer, Joyce Lee e Michelle M. Collins. "Modeling Human Cardiac Arrhythmias: Insights from Zebrafish". Journal of Cardiovascular Development and Disease 9, n. 1 (5 gennaio 2022): 13. http://dx.doi.org/10.3390/jcdd9010013.

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Cardiac arrhythmia, or irregular heart rhythm, is associated with morbidity and mortality and is described as one of the most important future public health challenges. Therefore, developing new models of cardiac arrhythmia is critical for understanding disease mechanisms, determining genetic underpinnings, and developing new therapeutic strategies. In the last few decades, the zebrafish has emerged as an attractive model to reproduce in vivo human cardiac pathologies, including arrhythmias. Here, we highlight the contribution of zebrafish to the field and discuss the available cardiac arrhythmia models. Further, we outline techniques to assess potential heart rhythm defects in larval and adult zebrafish. As genetic tools in zebrafish continue to bloom, this model will be crucial for functional genomics studies and to develop personalized anti-arrhythmic therapies.

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Li, Jie, Bin Li, Hailiang Huang, Tao Han e Yang Li. "Allocryptopine: A Review of Its Properties and Mechanism of Antiarrhythmic Effect". Current Protein & Peptide Science 20, n. 10 (20 settembre 2019): 996–1003. http://dx.doi.org/10.2174/1389203720666190807123609.

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Abstract：Throughout the last decade, extensive efforts have been devoted to developing a percutaneous catheter ablation and implantable cardioverter-defibrillator technique for patients suffering from ventricular arrhythmia. Antiarrhythmic drug efficacy for preventing arrhythmias remains disappointing because of adverse cardiovascular effects. Allocryptopine is an isoquinoline alkaloid widely present in medicinal herbs. Studies have indicated that allocryptopine exhibits potential anti-arrhythmic actions in various animal models. The potential therapeutic benefit of allocryptopine in arrhythmia diseases is addressed in this study, focusing on multiple ion channel targets and reduced repolarization dispersion. The limitations of allocryptopine research are clear given a lack of parameters regarding toxicology and pharmacokinetics and clinical efficacy in patients with ventricular arrhythmias. Much remains to be revealed about the properties of allocryptopine.

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Più fonti

Tesi sul tema "Arrhythmia"

Walfridsson, Ulla. "Assessing Symptom Burden and Health-Related Quality of Life in patients living with arrhythmia and ASTA : Arrhythmia-Specific questionnaire in Tachycardia and Arrhythmia". Doctoral thesis, Linköpings universitet, Omvårdnad, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71873.

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Background: Health-Related Quality of Life (HRQOL) can be negatively affected in patients living with arrhythmias and many patients experience a pronounced symptom burden. The arrhythmia can cause both uncertainty and limitations, including interference with work, reluctance to perform and plan for leisure activities and leading to self-imposed restrictions in daily life situations. There are patients striving to find strategies to manage the arrhythmia and for some this can become the focus in their lives. Treatment options are often a choice between pharmaceuticals and radiofrequency ablation (RFA) where RFA is an option for many arrhythmia-patients to be cured. In the care of arrhythmia-patients it is of great importance to combine objective examinations with patient-reported outcomes (PROs) to achieve patient’s own experiences of treatment efficacy and arrhythmias interference in daily life situations. Aims: The overall aims of this thesis were to assess symptom burden and HRQOL in patients with arrhythmias and to develop and validate an arrhythmia-specific questionnaire, suitable for most arrhythmia-patients. Design and Methods: Studies I and II were single-centre studies including patients referred for RFA, with two different arrhythmia diagnoses. Assessments of patient-reported outcomes (PROs) concerning HRQOL were performed using two questionnaires, SF-36 and EQ-5D (I-II). Further, patients were asked some disease-specific questions (I). Study I describes assessments before the RFA treatment and Study II the follow-up assessments at three and twelve months after RFA. Patients’ scoring of HRQOL was compared to age and gender matched reference groups before and after RFA (I-II). Studies III and IV describe the development and validation of a disease-specific questionnaire ASTA (Arrhythmia-Specific questionnaire in Tachycardia and Arrhythmia) assessing symptom burden and HRQOL. Studies III and IV were multicentre studies. Patients planned for DC-conversion, AF patients seeking emergency care and those with different forms of arrhythmias referred for RFA were included. Results: Patients scored significantly lower HRQOL in seven of SF-36’s eight scales compared to the age and gender matched reference groups before RFA treatment. Frequent arrhythmia attacks had a great negative impact on HRQOL, and female gender and older age were factors contributing to worse HRQOL (I). Treatment with RFA restored the patients’ HRQOL. Most positive effects were seen at three months follow-up. One year after treatment patients and the matched reference group scored their HRQOL to a similar level, assessed with SF-36 and EQ-5D index (II). The validated ASTA questionnaire was found to have good psychometric properties. Construct validity was confirmed with sufficient levels of item-total correlations in the ASTA symptom burden scale and HRQOL scales. The dimensionality of the ASTA HRQOL scale was established with confirmatory factor analysis, supporting a physical and a mental subscale. The internal consistency, demonstrated with Cronbach’s alpha (α), was satisfactory for the ASTA symptom burden scale and the ASTA HRQOL scales, varying from α 0.79 to α 0.91 (III-IV). Conclusions and clinical implications: The studies in this thesis confirmed how negatively affected the arrhythmia-patients can be with a pronounced symptom burden and impaired HRQOL. Treatment with RFA was demonstrated to restore the patients HRQOL to an equal level of that of the matched reference group. PROs are important to take into consideration in the care of arrhythmia-patients, to achieve the patients’ subjective experiences of their daily life situation. To the best of our knowledge ASTA is the first arrhythmia-specific questionnaire assessing symptom burden and HRQOL, suitable for most arrhythmia forms. The newly validated ASTA questionnaire can be an important contribution to assessment of PROs in arrhythmia-patients.

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Williams, Steven Edwin. "Characterisation and representation of arrhythmia substrates". Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/characterisation-and-representation-of-arrhythmia-substrates(b591acfd-9ca4-45a0-a3b0-169128bac9d7).html.

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Cardiac arrhythmias arise from a variety of structural and electrical substrates and range in clinical presentation from asymptomatic to severely disabling or life threatening. Existing techniques for the characterisation of arrhythmia substrates include surface electrocardiography and intracardiac mapping together with ultrasound, computed tomography and magnetic resonance imaging. In this thesis I study a spectrum of arrhythmia characterisation techniques to improve the understanding of complex arrhythmia mechanisms. The role of surface electrocardiography and intra-cardiac contact mapping together with cardiac magnetic resonance imaging are studied in a variety of atrial and ventricular arrhythmias as well as in an animal model of atrial ablation. Arrhythmia characterisation techniques result in large quantities of data that are frequently considered in combination with other modalities and visualised within the 3- dimensional nature of cardiac structures. Since no techniques are currently available to display multiple parameters without loss of fidelity of either parameter, I developed a new system for data representation. Termed Dot Mapping, this system allows two or more datasets to be concurrently displayed by using separate visual entities (colour and dots) for each. The function, development and feasibility of the system are studied. In summary, this thesis explores and develops a number of techniques for assessing arrhythmia substrates, including surface electrocardiography, intra-cardiac mapping and cardiac magnetic resonance imaging. New (and existing) data thus created are displayed using a new data representation technique designed to optimise the co-display of multiple related modalities.

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Fischer, Lindsey Ann. "How Emotions Affect Respiratory Sinus Arrhythmia". Thesis, The University of Arizona, 2015. http://hdl.handle.net/10150/579276.

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Respiratory sinus arrhythmia (RSA) is a measure of heart rate variability in relation to respiration. The current study investigated how the different induced emotional states (i.e., amusement, anger, disgust, happiness, fear, and sadness) affect RSA. This was done by comparing resting RSA to that occurring while watching short film clips intended to induce emotional states. It was hypothesized that RSA would be lower when negative emotions are induced and higher when positive emotions are induced. A difference between the resting RSA and RSA measured during emotion induction was also anticipated. Results indicated a marginally significant difference in RSA between film clip 1 and resting with eyes open and between film clip 1 and film clip 2. There was also a trend in RSA between male and female participants.

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Ware, James. "Genomic dissection of arrhythmia and cardiac electromechanics". Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/39405.

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Cardiac arrhythmia is a leading cause of death in the developed world and a final common pathway for many forms of cardiac disease. Rare inherited arrhythmia syndromes contribute to this disease burden, particularly through sudden death in the young. The study of rare syndromes, such as inherited arrhythmia, can also identify genes and pathways important in common diseases. Here, genomic approaches were applied to dissect genetic determinants of cardiac arrhythmia, through gene discovery, variant discovery, and variant annotation. First, whole-exome sequencing was used to identify the genetic basis of an unexplained inherited arrhythmia syndrome. Linkage analysis and conventional sequencing excluded known causative genes in a family with Brugada Syndrome, and whole exome sequencing identifie d a shortlist of five new candidate genes that may lead to a genetic diagnosis in this family and new insights into the pathogenesis of the condition. Following the identification of genes responsible for inherited arrhythmia syndromes, the recognition of specific disease-causing variants in those genes allows for clinical application, including molecular diagnosis, cascade screening and stratified therapy. Here, two high-throughput next-generation sequencing approaches for the detection of variants in these genes were compared, technically evaluated, and optimis ed. This represents the de novo establishment of next-generation sequencing technologies and analysis pathways in our laboratory, and provides a platform for molecular diagnosis and future genotype-phenotype correlation studies. Finally, a novel approach for the functional annotation of non-synonymous variants was developed. This approach, termed 'Paralogous Annotation', identifies functionally important, disease-associated residues across protein families using multiple sequence alignment. Paralogous Annotation was validated here by demonstrating the accurate identification of disease-causing variation in genes that cause long QT syndrome - an important cause of sudden death. This methodology is widely applicable to annotate Mendelian human disease genes.

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Kehrle, Florian [Verfasser]. "Inverse simulation for cardiac arrhythmia / Florian Kehrle". Magdeburg : Universitätsbibliothek, 2018. http://d-nb.info/1160593698/34.

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Soto-Freita, Angelica Marie. "Parent Predictors of Infant Respiratory Sinus Arrhythmia". TopSCHOLAR®, 2016. http://digitalcommons.wku.edu/theses/1628.

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The development of emotion regulation skills is an imperative task early in development. Respiratory sinus arrhythmia (RSA), a physiological proxy of regulation, is indicative of one’s regulatory capacity and can be predictive of behavior in later life (Graham, Ablow, & Measelle, 2010; Moore, 2010). Children begin regulating their emotions at a physiological level early in infancy. Infants who are able to properly suppress RSA have higher quality social interactions in childhood (Graziano, Keane, & Calkins, 2007). Previous work has suggested that parents play a role in predicting infant RSA (Conradt & Ablow, 2010). For example, parent marital satisfaction is known to impact infants’ physiological regulation, such that infants whose parents are less satisfied with their marriages have a decreased ability to regulate physiologically (Moore et al., 2009; Porter, Wouden-Miller, Silva, & Porter, 2003). Previous research has found that parent personality impacts parenting strategies (Cummings & Davies, 1994; Prinzie, Stams, Deković, Reijntjes, & Belsky, 2009), however work examining how parent personality interacts with marital satisfaction to predict infant RSA is lacking. Moreover, the majority of previous work assessing the parent predictors of infant RSA focused on mothers (e.g., Moore et al., 2009). There are known differences in the way mothers and fathers interact with their infants, as well as differences in the way fathers and mothers respond to marital dissatisfaction (Forbes, Cohn, Allen, & Lewinsohn, 2004; Karney & Bradbury, 1995). The present study focused on examining how marital satisfaction and parent personality predicts infant RSA with mothers and fathers. The current study involved 38 families (6-month old infants, mothers, and fathers). Parents completed questionnaires measuring marital satisfaction and personality. Mother-infant and fatherinfant dyads participated in a baseline and face-to-face play task (Still Face Paradigm; Tronick, Als, Adamson, Wise, & Brazelton, 1978), where infant physiological regulation was assessed. Results involving mothers did not yield significant findings predicting infant physiological regulation. For fathers, results indicated that parent personality and parent marital satisfaction predicted infant physiological regulation. The current study highlights the importance of examining the roles of both mothers and fathers predicting infant physiological regulation.

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Labarge, Isaac E. "Neural Network Pruning for ECG Arrhythmia Classification". DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2136.

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Convolutional Neural Networks (CNNs) are a widely accepted means of solving complex classification and detection problems in imaging and speech. However, problem complexity often leads to considerable increases in computation and parameter storage costs. Many successful attempts have been made in effectively reducing these overheads by pruning and compressing large CNNs with only a slight decline in model accuracy. In this study, two pruning methods are implemented and compared on the CIFAR-10 database and an ECG arrhythmia classification task. Each pruning method employs a pruning phase interleaved with a finetuning phase. It is shown that when performing the scale-factor pruning algorithm on ECG, finetuning time can be expedited by 1.4 times over the traditional approach with only 10% of expensive floating-point operations retained, while experiencing no significant impact on accuracy.

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Goetz, Paul W. "Worry, Respiratory Sinus Arrhythmia, and Health Behaviors". Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1308552215.

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Korhonen, Petri. "Magnetocardiography in assessment of ventricular arrhythmia risk". Helsinki : University of Helsinki, 2002. http://ethesis.helsinki.fi/julkaisut/laa/kliin/vk/korhonen/.

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Ye, Yanping. "Designing New Drugs to Treat Cardiac Arrhythmia". PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/638.

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Heart failure resulting from different forms of cardiomyopathy is defined as the inability of the heart to pump sufficient blood to meet the body's metabolic demands. It is a major disease burden worldwide and the statistics show that 50% of the people who have the heart failure will eventually die from sudden cardiac death (SCD) associated with an arrhythmia. The central cause of disability and SCD is because of ventricular arrhythmias. Genetic mutations and acquired modifications to RyR2, the calcium release channel from sarcoplasmic reticulum, can increase the pathologic SR Ca2+ leak during diastole, which leads to defects in SR calcium handling and causes ventricular arrhythmias. The mechanism of RyR2 dysfunction includes abnormal phosphorylation, disrupted interaction with regulatory proteins and ions, or altered RyR2 domain interactions. Many pharmacological strategies have shown promising prospects to modulate the RyR2 as a therapy for treating cardiac arrhythmias. Here, we are trying to establish a novel approach to designing new drugs to treat heart failure and cardiac arrhythmias. Previously, we demonstrated that all pharmacological inhibitors of RyR channels are electron donors while all activators of RyR channels are electron acceptors. This was the first demonstration that an exchange of electrons was a common molecular mechanism involved in modifying the function of the RyR. Moreover, we found that there is a strong correlation between the strength of the electron donor/acceptor, and its potency as a channel inhibitor/activator, which could serve as a basis and direction for developing new drugs targeting the RyR. In this study, two new potent RyR inhibitors, 4-methoxy-3-methyl phenol (4-MmC) and the 1,3 dioxole derivative of K201, were synthesized which are derivatives of the known RyR modulators, 4-chloro-3-methyl phenol (4-CmC) and K201. The ability of K201, 1,3 dioxole derivative of K201 and 4-MmC to inhibit the cardiac calcium channel is examined and compared at the single channel level. All of these compounds inhibited the channel activity at low micromolar concentrations or sub-micromolar concentrations.

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Libri sul tema "Arrhythmia"

A, Kastor John, a cura di. Arrhythmias. Philadelphia: W.B. Saunders, 1993.

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1937-, Mandel William J., a cura di. Cardiac arrhythmias: Their mechanisms, diagnosis, and management. 2^a ed. Philadelphia: Lippincott, 1987.

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1937-, Mandel William J., a cura di. Cardiac arrhythmias: Their mechanisms, diagnosis, and management. 3^a ed. Philadelphia: Lippincott, 1995.

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J, Podrid Philip, e Kowey Peter R, a cura di. Handbook of cardiac arrhythmia. Baltimore: Williams & Wilkins, 1996.

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A, Payne Wayne, a cura di. Focus on health. 6^a ed. Boston: McGraw-Hill, 2003.

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A, Payne Wayne, a cura di. Focus on health. St. Louis: Mosby Year Book, 1991.

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Hahn, Dale B. Focus on health. New York: McGraw-Hill, 2011.

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Hahn, Dale B. Focus on health. St. Louis: MosbyYear Book, 1990.

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Hahn, Dale B. Focus on health. 4^a ed. Boston: WCB/McGraw-Hill, 1999.

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A, Payne Wayne, e Mauer Ellen, a cura di. Focus on health. 9^a ed. New York, NY: McGraw-Hill, 2009.

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Capitoli di libri sul tema "Arrhythmia"

Abrams, David B., J. Rick Turner, Linda C. Baumann, Alyssa Karel, Susan E. Collins, Katie Witkiewitz, Terry Fulmer et al. "Arrhythmia". In Encyclopedia of Behavioral Medicine, 126–27. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4419-1005-9_726.

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Colombo, Joseph, Rohit Arora, Nicholas L. DePace e Aaron I. Vinik. "Arrhythmia". In Clinical Autonomic Dysfunction, 197–204. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-07371-2_18.

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Pulgaron, Elizabeth R., e Diana Wile. "Arrhythmia". In Encyclopedia of Behavioral Medicine, 147–48. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-39903-0_726.

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Miyoshi, Takekazu. "Arrhythmia". In Maternal and Fetal Cardiovascular Disease, 185–200. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-1993-7_16.

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Salgirli, Saygin. "Arrhythmia". In The Fluctuating Sea, 269–76. London: Routledge, 2021. http://dx.doi.org/10.4324/9781003100706-6.

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Westermann, Melissa, e Afshan B. Hameed. "Arrhythmia". In Expecting Trouble, 31–40. Boca Raton, FL : CRC Press/Taylor & Francis Group, [2018]: CRC Press, 2018. http://dx.doi.org/10.4324/9781351215145-5.

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Saarel, Elizabeth V., e Carlen Gomez. "Fetal Arrhythmia". In Developments in Cardiovascular Medicine, 241–56. Boston, MA: Springer US, 2006. http://dx.doi.org/10.1007/0-387-29170-9_19.

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Miyoshi, Takekazu. "Fetal Arrhythmia". In Maternal and Fetal Cardiovascular Disease, 213–26. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-1993-7_18.

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Santilli, Roberto A., e Manuela Perego. "Arrhythmia Ablation". In Veterinary Image-Guided Interventions, 531–40. Oxford: John Wiley & Sons, Ltd, 2015. http://dx.doi.org/10.1002/9781118910924.ch54.

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Parikh, Milind G. "Arrhythmia Syndromes". In Cardiac Electrophysiology, 287–328. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-75326-9_9.

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Atti di convegni sul tema "Arrhythmia"

Malidze, David, Rishu Bansal, Marina Noniashvili, Natia JoJua, Tinatin Gognadze e Mreisa Ahmad. "Cardiac Arrhythmias in Patients with Myocarditis in the Post-COVID-19 Period". In Socratic Lectures 8. University of Lubljana Press, 2023. http://dx.doi.org/10.55295/psl.2023.ii1.

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To date, several cardiotropic viruses have been implicated as causes of myocarditis. The most detected are parvovirus B19, and human herpes virus 6. Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) are the respiratory viruses that have recently triggered the unprecedented pandemic process. The involvement and impact of these viruses in viral cardiovascular disease are under study. Despite extensive research into the pathological mechanisms of viral infections of the cardiovascular system, our knowledge regarding their treatment and management is still incomplete. A condition caused by post- Co rona Virus Disease (COVID-19) myocarditis seems to have distinct inflammatory characteristics. Many kinds of arrhythmias may occur in patients with post-COVID-19 myocarditis and result in arrhythmogenic cardio-myopathy and sudden cardiac death. Sometimes arrhythmia can be the first and only symptom of myocarditis. However, compared to the other clinical presentations, arrhythmic myocarditis has been poorly described in the literature. The increased risk of arrhythmias in patients with a post-COVID-19 period is most likely a consequence of systemic inflammation and diseases, not just a direct consequence of the viral infection. A decrease in heart rate variability can contribute to electrical instability of the myocardium and the occurrence of arrhythmias. Cardiac magnetic resonance imaging and endomyocardial biopsy are the most useful tests for myocarditis. However, different from the other clinical presentations, arrhythmic myocarditis requires specific diagnostic, prognostic, and therapeutic considerations. This review aims to critically summarize the state of the art on myocarditis presenting with arrhythmias in terms of epidemiology, aetiology, diagnosis, prognosis, and treatment. Keywords: Post-COVID-19; SARS-CoV-2; Myocarditis; Arrhythmias; Ferroptosis; Vaccination

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Silva, Guilherme, Arthur Negrão, Gladston Moreira, Eduardo Luz e Pedro Silva. "An Embedding Multitask Neural Network for Efficient Arrhythmia Detection". In Simpósio Brasileiro de Computação Aplicada à Saúde. Sociedade Brasileira de Computação - SBC, 2024. http://dx.doi.org/10.5753/sbcas.2024.2378.

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This study addresses the critical need for prompt detection of life-threatening ventricular arrhythmias. We explore the application of neural networks within the constraints of Implantable Cardioverter Defibrillators to improve early arrhythmia detection. Our proposed neural network methodology leverages multitask learning, aiming to enhance detection efficiency by concurrently learning to identify ventricular arrhythmias and estimate RR intervals from intracardiac electrograms. Implemented on the NUCLEO-L432KC board, with limited memory and processing capacity, our approach achieved an Fβ score of 0.88, with a low inference latency of 59.96 ms. These results demonstrate the feasibility of integrating advanced neural network capabilities within Implantable Cardioverter Defibrillators (ICDs).

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Rege, Sanket, Tyler Barkey e Mariano Lowenstern. "Heart arrhythmia detection". In 2015 IEEE Virtual Conference on Applications of Commercial Sensors (VCACS). IEEE, 2015. http://dx.doi.org/10.1109/vcacs.2015.7439569.

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Wu, Meng-Hsi, e Edward Y. Chang. "DeepQ Arrhythmia Database". In MM '17: ACM Multimedia Conference. New York, NY, USA: ACM, 2017. http://dx.doi.org/10.1145/3132635.3132647.

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Ozdemir, Ahmet Turan, Kenan Danisman e Musa Hakan Asyali. "FPGA based arrhythmia classifier". In 2009 14th National Biomedical Engineering Meeting. IEEE, 2009. http://dx.doi.org/10.1109/biyomut.2009.5130253.

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Comondore, Vikram R., Sung Hong, Iqwal Mangat e Richard Leung. "Sinus Arrhythmia-Related Aberrancy". In American Thoracic Society 2011 International Conference, May 13-18, 2011 • Denver Colorado. American Thoracic Society, 2011. http://dx.doi.org/10.1164/ajrccm-conference.2011.183.1_meetingabstracts.a5268.

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Daoming, Zhang, Tan Guojun, Hao Jifei e Han Yaofei. "Ventricular Arrhythmia Nonlinear Analysis". In The 2007 International Conference on Intelligent Pervasive Computing (IPC 2007). IEEE, 2007. http://dx.doi.org/10.1109/ipc.2007.37.

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Ghanwat Tejaswini B. "Arrhythmia & neural network". In 2015 International Conference on Communications and Signal Processing (ICCSP). IEEE, 2015. http://dx.doi.org/10.1109/iccsp.2015.7322731.

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"COMBINATORIAL DETECTION OF ARRHYTHMIA". In International Conference on Bio-inspired Systems and Signal Processing. SciTePress - Science and and Technology Publications, 2010. http://dx.doi.org/10.5220/0002696501800187.

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Phan, A. T., D. Robinson, S. Nguyen, H. Azhand e D. Vo. "Mirtazapine-Induced Ventricular Arrhythmia". In American Thoracic Society 2024 International Conference, May 17-22, 2024 - San Diego, CA. American Thoracic Society, 2024. http://dx.doi.org/10.1164/ajrccm-conference.2024.209.1_meetingabstracts.a5701.

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Rapporti di organizzazioni sul tema "Arrhythmia"

Ye, Yanping. Designing New Drugs to Treat Cardiac Arrhythmia. Portland State University Library, gennaio 2000. http://dx.doi.org/10.15760/etd.638.

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Jinming, Song, Tang Yao, Gao Chao e Xu Zongpei. Efficiency between Guan-fu base A versus propafenone in the treatment of arrhythmia: a meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, marzo 2021. http://dx.doi.org/10.37766/inplasy2021.3.0077.

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yang, yan, qian huang, rui zeng, xinyue zhang, ping liu, gang luo, sijin yang e qin sun. Randomized Controlled Trials of Zhigancao Decoction Combined with Metoprolol in the Treatment of Arrhythmia: A Systematic Review and Meta-Analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, ottobre 2021. http://dx.doi.org/10.37766/inplasy2021.10.0045.

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Zhang, Lei, Lan-Chun Liu e Jie Wang. The Effectiveness and Safety of Wenxin granule combined with western medicine on Treating Chronic Pulmonary Heart Disease with Arrhythmia : A Meta-Analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, marzo 2024. http://dx.doi.org/10.37766/inplasy2024.3.0060.

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Pshezhetskiy, Dmitry, Tanveer Alam e Heba Alshaker. Unsynchronised Cardioversion as a Cause of Ventricular Tachycardia in a Patient with Atrial Fibrillation. Nature Library, novembre 2020. http://dx.doi.org/10.47496/nl.ccr.2020.01.02.

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Background: Synchronised cardioversion (SC) is used to terminate tachycardic arrhythmia by applying electric current to the thorax. SC is synchronised to the R wave of the cardiac cycle and ventricular tachycardia (VT) or ventricular fibrillation (VF) can occur if an electrical shock is provided in a nonsynchronised way. Case Presentation: Here we present a case of a 66-year-old man who had elective cardioversion for atrial fibrillation worsened by severe left ventricular impairment. A manual defibrillator was used for the cardioversion, which, after the first synchronised shock, reverted to defibrillator mode. An unsynchronised shock was administered and induced VT, which was reverted to sinus rhythm with a defibrillation shock. Conclusion: When using manual defibrillator for SC, the machine needs to be set to a synchronised mode. The synchronisation to the R wave needs to be checked before every shock.

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Xi, Yin, Zheng Gao, Jiyuan Ni, Yang Li, Wenyu Zhang e Jie Hao. Comparative efficacy of “contact force” ablation, adenosine, cryoballoon and waiting time after PVI for freedom from arrhythmia recurrence undergoing PVI : A network meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, maggio 2022. http://dx.doi.org/10.37766/inplasy2022.5.0076.

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Dong, Zhenyu, Muyassar Yusup, Yanmei Lu e Baopeng Tang. The effectiveness of angiotensin receptor-neprilysin inhibitor in ventricular arrhythmia in patients with Heart Failure with Reduced Ejection Fraction: a systematic review and meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, settembre 2021. http://dx.doi.org/10.37766/inplasy2021.9.0012.

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Shalganov, Tchavdar, Milko Stoyanov e Vassil Traykov. Outcomes following catheter ablation for ventricular tachycardia in adult patients with structural heart disease and implantable cardioverter-defibrillator: protocol for an updated systematic review and meta-analysis of randomized studies. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, giugno 2022. http://dx.doi.org/10.37766/inplasy2022.6.0080.

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Review question / Objective: Does catheter ablation for scar-related monomorphic ventricular tachycardia improve outcomes (defined as any appropriate ICD therapy, appropriate ICD shocks, all-cause mortality, VT storm, cardiovascular mortality, cardiovascular hospitalizations, complications) in adult patients with ischemic or non-ischemic cardiomyopathy and implantable cardioverter-defibrillator? Condition being studied: Ventricular tachycardia in patients with structural heart disease is usually an arrhythmia using the myocardial scar as a substrate for reentry. It poses a risk of syncope and sudden cardiac death, especially in patients with reduced ejection fraction. Most antiarrhythmic drugs are of little value and their use is restricted in patients with LV systolic dysfunction. Catheter ablation is a viable option for the treatment of ventricular tachycardia. In patients with previous myocardial infarction the arrhythmogenic scar is located most frequently subendocardially and is readily accessible using endocardial approach, while in non-ischemic cardiomyopathy the scar is frequently located in the midmyocardial or subepicardial layers. This is the reason endocardial catheter ablation to be less effective in those patients and to more often necessitate epicardial approach.

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Wagner, D. Ry, Eliezer Lifschitz e Steve A. Kay. Molecular Genetic Analysis of Flowering in Arabidopsis and Tomato. United States Department of Agriculture, maggio 2002. http://dx.doi.org/10.32747/2002.7585198.bard.

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The primary objectives for the US lab included: the characterization of ELF3 transcription and translation; the creation and characterization of various transgenic lines that misexpress ELF3; defining genetic pathways related to ELF3 function regulating floral initiation in Arabidopsis; and the identification of genes that either interact with or are regulated by ELF3. Light quality, photoperiod, and temperature often act as important and, for some species, essential environmental cues for the initiation of flowering. However, there is relatively little information on the molecular mechanisms that directly regulate the developmental pathway from the reception of the inductive light signals to the onset of flowering and the initiation of floral meristems. The ELF3 gene was identified as possibly having a role in light-mediated floral regulation since elj3 mutants not only flower early, but exhibit light-dependent circadian defects. We began investigating ELF3's role in light signalling and flowering by cloning the ELF3 gene. ELF3 is a novel gene only present in plant species; however, there is an ELF3 homolog within Arabidopsis. The Arabidopsis elj3 mutation causes arrhythmic circadian output in continuous light; however, we show conclusively normal circadian function with no alteration of period length in elj3 mutants in dark conditions and that the light-dependent arrhythmia observed in elj3 mutants is pleiotropic on multiple outputs regardless of phase. Plants overexpressing ELF3 have an increased period length in constant light and flower late in long-days; furthermore, etiolated ELF3-overexpressing seedlings exhibit a decreased acute CAB2 response after a red light pulse, whereas the null mutant is hypersensitive to acute induction. This finding suggests that ELF3 negatively regulates light input to both the clock and its outputs. To determine whether ELF3's action is phase dependent, we examined clock resetting by light pulses and constructed phase response curves. Absence of ELF3 activity causes a significant alteration of the phase response curve during the subjective night, and overexpression of ELF3 results in decreased sensitivity to the resetting stimulus, suggesting that ELF3 antagonizes light input to the clock during the night. Indeed, the ELF3 protein interacts with the photoreceptor PHYB in the yeast two-hybrid assay and in vitro. The phase ofELF3 function correlates with its peak expression levels of transcript and protein in the subjective night. ELF3 action, therefore, represents a mechanism by which the oscillator modulates light resetting. Furthermore, flowering time is dependent upon proper expression ofELF3. Scientifically, we've made a big leap in the understanding of the circadian system and how it is coupled so tightly with light reception in terms of period length and clock resetting. Agriculturally, understanding more about the way in which the clock perceives and relays temporal information to pathways such as those involved in the floral transition can lead to increased crop yields by enabling plants to be grown in suboptimal conditions.

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Zakroyeva, A. G., T. V. Zuyeva, E. V. Kuznetzova, I. V. Zhdanova, L. A. Maslova, T. A. Zhuravliova, A. I. Koryakov, Yu S. Kitaieva e E. A. Medvedskiy. Clinical and electrocardiographic signs of the heart arrhythmias. SIB-Expertise, febbraio 2023. http://dx.doi.org/10.12731/er0674.21022023.

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