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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Erfarenheter av att leva med förmaksflimmer : en litteraturöversikt / Experiences of living with atrial fibrillation : a literature review

Mattsson, Lina, Löfqvist, Michaela January 2020 (has links)
Förmaksflimmer är en av de vanligast förekommande hjärtrytmrubbningarna och är associerat med ökad sekundär sjukdom i hjärtsvikt och stroke, nedsatt livskvalitet och depression. Behandling riktas in på symtomlindring, upprätthållandet av god livskvalitet, och förebyggande av sjukdomsförsämring. Genom anpassad information kan hälso- och sjukvårdspersonal stödja personen att återfå kontroll över situationen. Personcentrerat förhållningssätt kan hjälpa till att bygga en förtroendefull vårdrelation, där professionell vägledning och känslomässigt stöd kan öka förmågan att följa livsstilsförändringar och läkemedelsbehandlingar. Syftet med denna studie var att belysa personers erfarenheter av att leva med förmaksflimmer. Litteraturöversikt med en strukturerad sökning användes som metod. Litteraturöversikten inkluderade 15 vetenskapliga artiklar, varav 13 artiklar kom från sökningar i databaserna PubMed och SweMed+. Två artiklar inkluderades genom manuell sökning. Inkluderade resultatartiklar kvalitetsgranskades, klassificerades och analyserades med integrerad analys. Resultatet presenteras med tre huvudkategorier och under dessa framkom totalt 9 underkategorier. Resultatet visade att personer med förmaksflimmer hade generellt lägre skattad livskvalitet och välbefinnande jämfört med övrig befolkning. Emotionell stress kunde upplevas i samband med återkommande episoder och vid misslyckade behandlingar. Många hade svåra symtom som medförde till att de fick avbryta sina dagliga aktiviteter. De önskade att få sin vård i en familjär och trygg miljö med bekanta lokaler och hälso- och sjukvårdspersonal, vilket gav ett ökat förtroende till vården. Bristande information från sjukvården gjorde att det fanns en stor osäkerhet kring sjukdomen. Tydliga förklaringar om situationen ingav en känsla av komfort och kontroll och kunde främja till en god vårdrelation. Många försökte hitta strategier för att förebygga episoder av förmaksflimmer och att identifiera orsaker. Personer upplevde en större tilltro till livsstilsförändringar och egenvård för att kunna kontrollera sjukdomen jämfört med behandlingar och procedurer. Slutsatsen med denna litteraturöversikt är att personer med förmaksflimmer hade generellt lägre skattad livskvalitet och välbefinnande samt upplevde begränsningar i det dagliga livet. Många försökte hitta strategier till att förebygga och hantera episoder av förmaksflimmer, flera strategier medförde till en ond cirkel med negativa konsekvenser. Personer med förmaksflimmer ville ha information och behöver kunskap om sjukdomen. Det skulle kunna vara viktigt att hälso- och sjukvårdspersonal ser personen bakom sjukdomen, istället för att fokusera på diagnos och behandling. Utifrån personens egen berättelse kan hälso- och sjukvårdspersonal få en förståelse av personens egna erfarenheter, önskemål och behov. / Atrial fibrillation is one of the most common heart rhythm disorders and is associated with poor quality of life and depression, and increased risks of secondary disease such as heart failure or stroke. Treatment is focused on relieving symptoms, maintaining a good quality of life, and preventing disease progression. Healthcare professionals can assist the person to regain control of the situation through personalized information. A person-centred attitude can help build a trusting care relationship, where professional guidance and emotional support can increase the ability to follow lifestyle changes and drug treatments. The purpose of this study was to highlight people's experiences of living with atrial fibrillation. This Literature review used a method with a structured search. The literature review included 15 scientific articles, 13 articles came from searches in the PubMed and SweMed+ databases. Two articles were included by manual search. Included articles were quality reviewed, classified and analysed with an integrated analysis. The results were presented with three categories and under these a total of nine subcategories emerged. The results showed that people with atrial fibrillation had generally lower estimated quality of life and well-being compared to the general population. Emotional stress could be experienced in conjunction with recurring episodes or failed treatments. Many had severe symptoms that led to their daily activities being interrupted. They wanted to get their care in a familiar and comfortable environment with familiar premises and medical staff, which gave them increased confidence in the care. Lack of information from the healthcare system meant that there was great uncertainty about the disease. Clear explanations of the situation provided a sense of comfort and control, which could promote a good care relationship. Many tried to find strategies to prevent and identify causes for episodes of atrial fibrillation. People experienced greater confidence in lifestyle changes and self-care in order to control the disease, compared to treatments and procedures. The conclusion of this literature review is that people with atrial fibrillation generally had lower estimated quality of life and well-being, and experienced limitations in daily life. Many people tried to find strategies for preventing and managing episodes of atrial fibrillation, however, some strategies led to a vicious cycle with negative consequences. Persons with atrial fibrillation want information and need knowledge about the disease. It may be important that health care professionals see the person behind the disease, rather than focusing on diagnosis and treatment. Based on the person's own story, healthcare professionals can gain an understanding of the person's own experiences, wishes and needs.
272

Predicting and classifying atrial fibrillation from ECG recordings using machine learning

Bogstedt, Carl January 2023 (has links)
Atrial fibrillation is one of the most common types of heart arrhythmias, which can cause irregular, weak and fast atrial contractions up to 600 beats per minute. Atrial fibrillation has increased prevalence with age and is associated with increased risks of ischemia, as blood clots can form due to the weak contractions. During prolonged periods of atrial fibrillation, the atria can undergo a process called atrial remodelling. This causes electrophysiological and structural changes to the atria such as increased atrial size and changes to calcium ion densities. These changes themselves promotes the initiation and propagation of atrial fibrillation, which makes early detection crucial. Fortunately, atrial fibrillation can be detected on an electrocardiogram. Electrocardiograms measures the electrical activity of the heart during its cardiac cycle. This includes the initiation of the action potential, the depolarization of the atria and ventricles and their repolarization. On the electrocardiogram recording, these are seen as peaks and valleys, where each peak and valley can be traced back to one of these events. This means that during atrial fibrillation, the weak, irregular and fast atrial contractions can all be detected and measured. The aim of this project was to develop a machine learning model that could predict onset of atrial fibrillation, and that could classify ongoing atrial fibrillation. This was achieved by training one multiclass classification machine learning model using XGBoost, and three binary classification machine learning models using ROSETTA, on electrocardiogram recordings of people with and without atrial fibrillation. XGBoost is a tree boosting system which uses tree-like structures to classify data, while ROSETTA is a rule-based classification model which creates rules in an IF and THEN format to make decisions. The recordings were labelled according to three different classes: no atrial fibrillation, atrial fibrillation or preceding atrial fibrillation. The XGBoost model had a prediction accuracy of 99.3%, outperforming the three ROSETTA models and other atrial fibrillation classification and prediction models found. The ROSETTA models had high accuracies on the learning set, however, the predictions were subpar, indicating faulty settings for this type of data. The results in this project indicate that the models created can be used to accurately classify and predict onset of and ongoing atrial fibrillation, serving as a tool for early detection and verification of diagnosis.
273

Investigations into the design and dissection of genetic networks

Libby, Eric. January 2007 (has links)
No description available.
274

Investigating the Contributions of Blood-Brain Barrier Dysfunction to the Risk of Cognitive Decline and Dementia in Individuals with Atrial Fibrillation

Marion, Danielle Lee 30 August 2022 (has links)
Despite evidence for an association between atrial fibrillation (AF) and cognitive decline and dementia independent of stroke, pathways underlying this relationship remain unclear. Critically, elevated levels of inflammatory markers, common in AF, are associated with the breakdown of the blood-brain barrier (BBB) and may contribute to neuroinflammation and neurodegeneration. To investigate this potential contributing pathway, we estimated associations of inflammatory markers with cognitive decline and dementia in AF adults. We used data from two population-based cohorts and found that inflammatory markers were associated with cognitive decline but not dementia. Some associations were modified by sex and apolipoprotein E (APOE) genotype. These findings provide preliminary evidence for inflammatory-mediated BBB dysfunction as a potential contributing pathway linking AF to cognitive decline. Future work examining the role of BBB dysfunction in AF and cognition may benefit from the use of markers of central inflammation to increase sensitivity, while considering possible differences by sex, dementia subtype, and APOE genotype.
275

Hälsorelaterad livskvalitet hos patienter med förmaksflimmer, samt vad som påverkar? : litteraturöversikt / Health related quality of life in patients with atrial fibrillation, and what influences? : literature review

Engel Riiga, Karin, Berisha Grainca, Shpresa January 2023 (has links)
Förmaksflimmer är den vanligaste hjärtarytmin globalt och associeras med ökad risk för utveckling av andra sjukdomar som negativt påverkar patientens hälsorelaterade livskvalitet. De flesta komorbida tillstånd som obesitas, hypertoni, alkoholöverkonsumtion, rökning, diabetes, och sömnapné kan påverkas genom livsstilsförändring. Att ändra på en levnadsvana är en utmaning och bör ses som en process. Genom att arbeta på ett personcentrerat förhållningssätt främjas patientens egen förmåga att förbättra livskvaliteten.  Syftet med denna litteraturöversikt var att undersöka hälsorelaterad livskvalitet hos personer med förmaksflimmer. Vilka är riskfaktorerna för en försämrad hälsorelaterad livskvalitet? Kan en förbättrad livsstil ge en bättre hälsorelaterad livskvalitet? Totalt granskades femton vetenskapliga artiklar med kvantitativ ansats. Databaserna som användes för att hitta artiklarna var PubMed och CINAHL. Artiklarna granskades utifrån Sophiahemmets Högskolas bedömningsunderlag. Artiklarna som inkluderades hade en god till hög kvalitet. Resultatet av artiklarnas analys sammanfattades av en integrerad dataanalys. Vid analysen framkom kategorier och underkategorier som beskrev artiklarnas resultat.  Resultatet sammanställdes från fyra huvudkategorier: Påverkan av faktorer, påverkan av livsstilmodifiering, påverkan av behandlingsstrategi och påverkan av könstillhörighet för patienter med förmaksflimmer. Resultatet visade att patienter med förmaksflimmer har försämrad hälsorelaterad livskvalitet och att kvinnor skattar sin hälsorelaterade livskvalitet generellt lägre än männen. De flesta riskfaktorer som sänker patientens hälsorelaterade livskvalitet bedöms vara modifierbara. Val av behandlingsstrategi påverkar patientens hälsorelaterade livskvalitet. Slutsats: Hälsorelaterad livskvalitet är oftast försämrad hos patienter med förmaksflimmer och underliggande riskfaktorer är modifierbara. Patientutbildning och stöd av specialistsjuksköterskan är fördelaktig och kan öka patientens hälsorelaterade livskvalitet. Nyckelord: Förmaksflimmer, livsstilsförändringar, livsstilsmodifiering, livskvalitet / Atrial fibrillation is the most common cardiac arrhythmia globally and is associated with increased risk of developing other diseases that negatively affect the patient's health-related quality of life. Most comorbid conditions like obesity, hypertension, alcohol overconsumption, smoking, diabetes, and sleep apnea can be affected by lifestyle change. Changing a lifestyle is a challenge and should be seen as a process. By working on a personcentered approach, the patient's own ability to improve quality of life is promoted. The purpose of this literature review was to investigate health-related quality of life in people with atrial fibrillation. What are the risk factors for a deterioration in health-related quality of life? Can an improved lifestyle provide a better health-related quality of life? A total of fifteen scientific articles with a quantitative approach were reviewed. The databases used to find the articles were PubMed and CINAHL. The articles were reviewed based on Sophiahemmet University's assessment data. The items included had a good to high quality. The results of the articles' analysis were summarized by an integrated data analysis. The analysis revealed categories and subcategories that described the results of the articles. The results were compiled from four main categories: Influence of factors, influence of lifestyle modification, influence of treatment strategy and influence of gender for patients with atrial fibrillation. The results showed that patients with atrial fibrillation have impaired health-related quality of life and that women rate their health-related quality of life generally lower than men. Most risk factors that lower the patient's health-related quality of life are considered modifiable. The choice of treatment strategy affects the patient's health-related quality of life. Conclusion: Health-related quality of life is most often impaired in patients with atrial fibrillation and underlying risk factors are modifiable. Patient education and the support of the specialist nurse are beneficial and can increase the patient's health-related quality of life.Keywords: Atrial fibrillation, lifestyle changes, lifestyle modification, quality of life
276

Catheter Insertion Mechanism for Real-Time MRI-Guided Robotic Assisted Cardiac Ablation

Ronderos, Diego 26 May 2023 (has links)
No description available.
277

Safety and Efficacy of Catheter Ablation for Atrial Fibrillation in Patients With Percutaneous Atrial Septal Closure Device: Electrophysiology Collaborative Consortium for Meta-Analysis—Electram Investigators

Garg, Jalaj, Shah, Kuldeep, Turagam, Mohit K., Janagam, Pragna, Natale, Andrea, Lakkireddy, Dhanunjaya 01 September 2020 (has links)
Introduction: Transseptal puncture (TSP) is challenging in patients with prior percutaneous atrial septal defect (ASD) occluder. We aimed to perform a systematic review and meta-analysis of the safety and efficacy of catheter ablation for atrial fibrillation (AF) in patients with percutaneous ASD occluder. Methods: We searched PubMed, Medline, Embase, Ovid, and Cochrane for studies reporting results of AF ablation (freedom from AF, fluoroscopy/procedure time, and complications) in patients with percutaneous ASD occluders. Results: Three studies with a total of 64 patients met inclusion criteria. The success rate of TSP was 100%. All patients (but one) underwent TSP under fluoroscopic and intracardiac echocardiography guidance. Freedom from AF was achieved in 77.7% (95% confidence interval [CI]: 65.7–86.3) patients. In the subgroup analysis, comparing septal versus device puncture, no significant difference in recurrence of AF was observed (23.07% vs. 16.66%; risk ratio: 1.18; 95% CI: 0.35–4.00; p =.79, respectively). The total fluoroscopy time was not significantly different in patients with TSP via native septum or device (43.50 vs. 70.67 min; p =.44), total procedural time was significantly longer with TSP via the closure device (237.3 vs. 180 min; p =.004) compared with the native septum. There were no device dislodgement or residual interatrial shunt during the follow-up period. Conclusion: Catheter ablation for AF in patients with prior percutaneous ASD closure device is feasible and safe with favorable long-term outcomes.
278

Stabilization of the Cardiac Nervous System During Cardiac Stress Induces Cardioprotection

Gibbons, David D. 01 May 2012 (has links) (PDF)
The cardiac nervous system consists of nested reflex feedback loops that interact to regulate regional heart function. Cardiac disease affects multiple components of the cardiac nervous system and the myocytes themselves. This study aims to determine: 1) how select components of the cardiac nervous system respond to acute cardiac stress, including myocardial ischemia (MI) and induced neural imbalance leading to cardiac electrical instability, and 2) how neuromodulation can affect neural-myocyte interactions to induce cardioprotection. Thoracic spinal cord stimulation (SCS) is recognized for its anti-anginal effects and ability to reduce apoptosis in response to acute MI, primarily via modulation of adrenergic efferent systems. The data presented here suggest that cervical SCS exerts similar cardioprotective effects in response to MI, but in contradistinction to thoracic SCS, uses both adrenergic and cholinergic efferent mechanisms to stabilize cardiomyocytes and the arrhythmogenic potential. SCS potentially can use efferent and/or anti-dromically activated cardiac afferents to mediate its cardioprotection. Thoracic SCS mitigates the MI-induced activation of both nodose and dorsal root ganglia cardiac-related afferents, doing so without antidromic activation of the primary cardiac afferents. Instead, thoracic SCS acts through altering the cardiac milieu thereby secondarily affecting the primary afferent sensory transduction. In response to cardiac stressors, reflex activation of efferent activity modifies mechanical and electrical functions of the heart. Excessive activation of neuronal input to the cardiac nervous system can induce arrhythmias. Stimulation of intrathoracic mediastinal nerves directly activates subpopulations of intrinsic cardiac neurons, thereby inducing atrial arrhythmias. Neuromodulation, either thoracic SCS or hexamethonium, suppressed mediastinal nerve stimulation (MSNS)-induced activation of intrinsic cardiac neurons and correspondingly reduced the arrhythmogenic potential. SCS exerted its stabilizing effects on neural processing and subsequent effects on atrial electrical function by selectively targeting local circuit neurons within the intrinsic cardiac nervous system. Together these data indicate that neuromodulation therapy, using SCS, can mitigate the imbalances in cardiac reflex control arising from acute cardiac stress and thereby has the potential to slow the progression of chronic heart disease.
279

A 3-Dimensional In Silico Test Bed for Radiofrequency Ablation Catheter Design Evaluation and Optimization

Teng, Carolyn 01 June 2019 (has links) (PDF)
Atrial fibrillation (AF) is the disordered activation of the atrial myocardium, which is a major cause of stroke. Currently, the most effective, minimally traumatic treatment for AF is percutaneous catheter ablation to isolate arrhythmogenic areas from the rest of the atrium. The standard in vitro evaluation of ablation catheters through lesion studies is a resource intensive effort due to tissue variability and visual measurement methods, necessitating large sample sizes and multiple prototype builds. A computational test bed for ablation catheter evaluation was built in SolidWorks® using the morphology and dimensions of the left atrium adjacent structures. From this geometry, the physical model was built in COMSOL Multiphysics®, where a combination of the laminar fluid flow, electrical currents, and bioheat transfer was used to simulate radiofrequency (RF) tissue ablation. Simulations in simplified 3D geometries led to lesions sizes within the reported ranges from an in-vivo ablation study. However, though the ellipsoid lesion morphologies in the full atrial model were consistent with past lesion studies, perpendicularly oriented catheter tips were associated with decreases of -91.3% and -70.0% in lesion depth and maximum diameter. On the other hand, tangentially oriented catheter tips produced lesions that were only off by -28.4% and +7.9% for max depth and max diameter. Preliminary investigation into the causes of the discrepancy were performed for fluid velocities, contact area, and other factors. Finally, suggestions for further investigation are provided to aid in determining the root cause of the discrepancy, such that the test bed may be used for other ablation catheter evaluations.
280

Patientens upplevelser av omvårdnaden vid förmaksflimmer : En litteraturstudie / Patients experiences of nursing care in atrial fibrillation : A literature review

Sundberg, Karin, Erlandsson, Louise January 2023 (has links)
Bakgrund: Förmaksflimmer är ur ett globalt perspektiv den mest förekommande arytmisjukdomen och prevalensen ökar i och med en åldrande befolkning. Sjukdomen kan påverka patienten fysiskt, psykiskt och socialt, vilket kan orsaka en sämre livskvalité. Genom livsstilsförändringar kan symtombördan minskas. Det leder till att patienter med förmaksflimmer är i behov av en personcentrerad omvårdnad utifrån ett helhetsperspektiv. Sjuksköterskans ansvarsområde är omvårdnad och den ska inkludera ett deltagande av patienten i planeringen och i utförandet för att främja hälsa. Syfte: Syftet var att belysa patientens upplevelser av omvårdnaden vid förmaksflimmer inom hälso- och sjukvården. Metod: En allmänlitteraturstudie. Resultat: Litteraturstudien resulterade i tre huvudkategorier: bristande information och utbildning, betydelsen av kontakt med sjuksköterskan och behov av stöd. Konklusion: Sjuksköterskan har en betydelsefull roll för patienter med förmaksflimmer och ansvarar för omvårdnaden. Omvårdnaden bör inkludera information och patientutbildning, samt stöd och hantering i patientens egenvård. Digitala alternativ för omvårdnad kan öka stödet och vara ett alternativ för att utöka omvårdnaden. / Background: From a global perspective, atrial fibrillation is the most common arrhythmia disease, and the prevalence is increasing with an aging population. The disease affects the patient physically, psychologically and socially, which can cause a poorer quality of life. Through lifestyle changes, the burden of symptoms can be reduced. That leads to patients with atrial fibrillation are in need of person-centered care based on a holistic perspective. The nurse's area of responsibility is nursing, that includes participation of the patient in the planning and in the execution and to promote health. Purpose: The aim was to illustrate the patients’ experiences of nursing care for atrial fibrillation within healthcare. Method: A general literature review. Results: The literature reviews results are presented in three categories: lack of information and education, importance of contact with the nurse and need for support. Conclusion: The nurse has an important role for patients with atrial fibrillation and is responsible for nursing care. Nursing care should include information and patient education, as well as support and management in the patient's self-care. Digital care can increase support and could be an option to extend nursing care.

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