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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.
131

Estudo comparativo do uso do antiagregante plaquetário e anticoagulante oral na profilaxia de trombose em pacientes submetidos à operação cavopulmonar total com tubo extracardíaco: análise ecorcardiográfica, angiotomográfica, cintililográfica, laboratorial e clínica / Comparative trial of the use of antiplatelet and oral anticoagulant in thrombosis prophylaxis in patients undergoing total cavopulmonary operation with extracardiac conduit: echocardiographic, tomographic, scintigraphic, clinical and laboratory analysis

Cristiane Felix Ximenes Pessotti 26 November 2013 (has links)
Estudo prospectivo e randomizado de 30 pacientes, submetidos a derivação cavopulmonar total com tubo extracardíaco. Os dados refletem o período de 2008 a 2011, com seguimento de dois anos, por meio de avaliação clínica, laboratorial, ecocardiográfica, angiotomográfica e cintilográfica. Neste estudo, procuramos comparar a eficácia do ácido acetil salicílico (AAS) e da Varfarina na profilaxia da trombose na população estudada. Para tanto, analisamos alterações nos fatores de coagulação (VII, VIII e Proteína C ); ou nos dados clínicos que predispusessem a ocorrência de trombo no pós-operatório. Além disso, no pós-operatório, após a randomização (15 pacientes randomizados para receber Varfarina, Grupo I, e 15 pacientes randomizados para receber AAS, Grupo II), estudamos a interferência da fenestração na ocorrência de trombo; alterações hemodinâmicas que pudessem contribuir com a ocorrência de trombo (fluxo lento pelo tubo extracardíaco), por meio de ecocardiograma transesofágico realizado com até 10 dias de pós operatório, 3, 6, 12 e 24 meses de pós operatório. A presença do fenômeno tromboembólico era pesquisada, além dos ecocardiogramas acima citados, por meio de consultas clínicas realizadas com a mesma periodicidade e que avaliavam, ainda, efeitos colaterais ou complicações no uso de cada uma das drogas. Avaliamos também a viabilidade e aderência ao uso de cada uma delas. O seguimento contou igualmente com a realização de angiotomografia aos 6, 12 e 24 meses de pós-operatório para avaliação de alterações na parede interna do tubo, bem como trombos e cintilografia pulmonar, ventilação-perfusão para avaliar possível tromboembolismo pulmonar. Durante o seguimento, ocorreram dois óbitos, ambos no grupo em uso de Varfarina. Ao todo, durante os dois anos de seguimento, 33,3% dos pacientes apresentaram fenômeno tromboembólico. Sendo que, entre os paciente em uso de AAS, 46,7% apresentaram tal complicação e 20% entre os pacientes em uso de Varfarina (p=0,121). Com relação a avaliação pré-operatória, a ocorrência prévia de trombo e baixos níveis de proteína C da coagulação foram os únicos fatores que influenciaram no tempo de sobrevida livre de trombo, com valores de p de 0,035 e 0,047 respectivamente. Ao final de dois anos de seguimento, na avaliação angiotomográfica, 35,7% dos pacientes em uso de AAS tinham material hiper-refringente depositado em tubo extracardíaco com espessura superior a 2mm ( p= 0,082). Já na avaliação por cintilografia de ventilação-perfusão, dois pacientes apresentaram sinais de tromboembolismo pulmonar, ambos em uso de AAS (p=0,483), e um deles com evolução desfavorável do circuito tipo Fontan. Com relação a segurança e aderência ao tratamento, cinco pacientes tiveram dificuldade de aderência (só viabilizada por tratar-se de protocolo de estudo), entre eles, quatro em uso de Varfarina e apresentando INR variando de 1 a 6,4. Para comprovação numérica, com força estatística dos dados encontrados, uma força tarefa deve ocorrer para que se consiga um grupo maior de pacientes incluídos neste estudo. No entanto, a diferença entre os dois grupos na evolução livre de trombo nos dois primeiros anos de pós-operatório não pode, e nem deve, ser ignorada / Prospective randomized trial of 30 patients who had undergone total cavopulmonary anastomosis via an extracardiac conduit. The data reflect the period between 2008 and 2011, with two-year follow-up, through clinical, laboratorial, echocardiographic, angiotomographic, and scintigraphic assessment. In this study, we aimed to compare the efficiency of ASA (Aspirin) and Warfarin in the preventive treatment of thrombosis in the tried population. For such, we\'ve analyzed changes in coagulation factors (VII, VIII and Protein C) or in the clinical data which would predispose the occurrence of postoperative thrombus. Moreover, during postoperative care, after randomization (15 patients randomly selected to be trated with Warfarin, referred to as Group I, and 15 patients randomly selected to be treated with ASA, referred to as Group II), we also studied the influence of fenestration in the occurrence of thrombus; hemodynamic variations which could contribute to the occurrence of thrombus (slow blood flow in the extracardiac conduit), with postoperative transesophageal echocardiogram being performed within 10 days, and thereafter 3, 6, 12 and 24 months. Besides the echocardiograms aforementioned, the presence of thromboembolic events was sought after by clinical appointments taking place with the same frequency, which evaluated, apart from thromboembolism, side effects or complications from the usage of each of the drugs. We\'ve also evaluated the compliance to and feasibility of each of them. Postoperative angiotomography was also performed during the follow-up, within 6, 12 and 24 months, for the evaluation of changes on the inside wall of the extracardiac conduit, as well as thrombi, and pulmonary ventilation/perfusion scintigraphy for assessment of pulmonary thromboembolism possibility. During the follow-up, two deaths were registered, both in the group being treated with Warfarin. Overall, in the two-year follow-up, 33,3% of the patients presented thromboembolic events. Among the group being treated with ASA, 46,7% presented such complication, whereas in the group being treated with Warfarin, 20% had the same complication (p=0,121). Regarding the preoperative evaluation, prior occurrence of thrombus and low levels of coagulation factor Protein C were the only variables which influenced living time without thrombus, with p-values of 0,035 and 0,047. At the end of the two-year follow-up, in the angiotomographic evaluation, 35,7% of patients treated with ASA presented material accumulation inside the extracardiac conduit, with over 2mm of thickness (p=0,082). As for the ventilation/perfusion scintigraphy, two patients presented traces of pulmonary thromboembolism, both treated with ASA (p=0,483), one of whom with unfavorable development of the Fontan circuit. Concerning safety and compliance to the treatment, five patients had difficulty to comply with the treatment (only viable for its trial nature), among those, four under treatment with Warfarin and presenting INR values ranging from 1 to 6,4. For quantitative verification, providing statistic value to the data, an effort must be made for a larger number of patients to be gathered and tried with this treatment. However, the difference in results concerning thrombus-free recovery between the two groups during the two years following surgery cannot, and must not, be ignored
132

Påverkan på PK(INR)-värdet efter olika preanalytiska behandlingar i venöst humanblod.

Khashayar, Mahdavisabet January 2015 (has links)
Venous thromboembolism that cause blood clotting in blood vessels, prevent blood circulation, depending on changes in one or more of the coagulation factors II, VII, IX and X. Patients who have had a blood clot or cardiovascular diseases are treated with oral anti-vitamin K (Warfarin®) to reducing and prevent relapse. Warfarin is also used as a preventive treatment before the disease. An overdose of Warfarin® may cause bleeding-complications and low dose cause blood clotting. The dosage of the drug is controlled by measuring prothrombin in plasma. The aim of this study was to investigate if prothrombin-complex value changes due to re-spinning and re-analysis after six hours. Fitty whole blood samples from warfarin-treated patients were divided into three subgroups, those with protrombinkomplex-values of 2-4 (n=20), >4 (n=15) and <2 (n=15). The samples were centrifugated and measured (Method A), re-centrifugated and measured (Method B) or re-analysed after six hours (Method C). All results were compared in a Bland-Altman plot as follows: Method B vs. Method A and Method C vs. Method A. The scatter graph yielded a strong correlation between Method A and Method B (R2=0.9984) and Method A and Methods C (R2=0.9977). The results from t-test showed a significance level (p<0.001) for both analyses (statistical significance=p<0.05). In this study we showed that prothrombin complex value ware stable after re-centrifugation and re-measurement after six hours. Statistical calculations yielded a strong correlation between the methods (A, B, C), and there was no significance difference between the methods.
133

A Population-Based Perspective on Clinically Recognized Venous Thromboembolism: Contemporary Trends in Clinical Epidemiology and Risk Assessment of Recurrent Events: A Dissertation

Huang, Wei 05 November 2014 (has links)
Background: Venous thromboembolism (VTE), comprising the conditions of deep vein thrombosis (DVT) and pulmonary embolism (PE), is a common acute cardiovascular event associated with increased long-term morbidity, functional disability, all-cause mortality, and high rates of recurrence. Major advances in identification, prophylaxis, and treatment over the past 3-decades have likely changed its clinical epidemiology. However, there are little published data describing contemporary, population-based, trends in VTE prevention and management. Objectives: To examine recent trends in the epidemiology of clinically recognized VTE and assess the risk of recurrence after a first acute episode of VTE. Methods: We used population-based surveillance to monitor trends in acute VTE among residents of the Worcester, Massachusetts, metropolitan statistical area (WMSA) from 1985 through 2009, including in-hospital and ambulatory settings. Results: Among 5,025 WMSA residents diagnosed with acute PE and/or lower-extremity DVT between 1985 and 2009 (mean age = 65 years), 46% were men and 95% were white. Age- and sex-adjusted annual event rates (per 100, 000) of clinically recognized acute first-time and recurrent VTE was 142 overall, increasing from 112 in 1985/86 to 168 in 2009, due primarily to increases in PE occurrence. During this period, non-invasive diagnostic VTE testing increased, vi while treatment shifted from the in-hospital (chiefly with warfarin and unfractionated heparin) to out-patient setting (chiefly with low-molecular-weight heparins and newer anticoagulants). Among those with community-presenting first-time VTE, subsequent 3-year cumulative event rates of key outcomes decreased from 1999 to 2009, including all-cause mortality (41% to 26%), major bleeding episodes (12% to 6%), and recurrent VTE (17% to 9%). Active-cancer (with or without chemotherapy), a hypercoagulable state, varicose vein stripping, and Inferior vena cava filter placement were independent predictors of recurrence during short- (3-month) and long-term (3-year) follow-up after a first acute episode of VTE. We developed risk score calculators for VTE recurrence based on a 3-month prognostic model for all patients and separately for patients without active cancer. Conclusions: Despite advances in identification, prophylaxis, and treatment between 1985 and 2009, the disease burden from VTE in residents of central Massachusetts remains high, with increasing annual events. Declines in the frequency of major adverse outcomes between 1999 and 2009 were reassuring. Still, mortality, major bleeding, and recurrence rates remained high, suggesting opportunities for improved prevention and treatment. Clinicians may be able to use the identified predictors of recurrence and risk score calculators to estimate the risk of VTE recurrence and tailor outpatient treatments to individual patients.
134

Trombofilias maternas hereditárias com e sem tromboembolismo venoso: resultados maternos e neonatais / Maternal inherited thrombophilias with or without venous thromboembolism: maternal and neonatal outcomes

Oliveira, André Luiz Malavasi Longo de 06 July 2010 (has links)
O objetivo do presente estudo foi avaliar a diferença de resultados maternos e neonatais em gestações complicadas por trombofilias hereditárias em pacientes com e sem tromboembolismo venoso. Apesar do aumento de evidências, na literatura, sobre a associação de trombofilias congênitas e resultados obstétricos adversos, há ainda dúvida se pacientes trombofílicas com tromboembolismo venoso apresentam resultados maternos e neonatais piores que as pacientes trombofílicas sem tromboembolismo venoso. O estudo analisou 66 gestantes com trombofilias hereditárias, de forma retrospectiva observacional e comparativa, das quais 33 apresentavam tromboembolismo venoso e 36 o não apresentavam. Os principais desfechos relacionados a resultados maternos e neonatais adversos foram: pré-eclâmpsia grave, descolamento prematuro de placenta, restrição de crescimento fetal, natimortalidade, prematuridade e complicações hemorrágicas maternas. As trombofilias congênitas incluídas no estudo foram o fator V de Leiden (FVL), mutação da protrombina G20210A, mutação C677T do gene da 5,10-metilenotetrahidrofolato redutase (MTHFR), deficiência de proteína S, deficiência de proteína C e deficiência de antitrombina. Ambos os grupos apresentaram características populacionais similares. A ocorrência de complicações maternas e fetais/neonatais foi similar nos dois grupos: pré-eclâmpsia grave (P=0,097), descolamento prematuro de placenta (P=0,478), restrição de crescimento fetal (P=0,868), natimortalidade (P=0,359), prematuridade (P=0,441) e complicações hemorrágicas maternas (P=0,478). Este estudo concluiu que a presença de tromboembolismo venoso em gestantes com trombofilia hereditária apresenta resultados maternos e neonatais semelhantes àquelas com trombofilias hereditárias sem tromboembolismo venoso. / The aim of this study was to evaluate differences in maternal and neonatal outcomes in pregnancies complicated by inherited thrombophilias between patients with and without venous thromboembolism. Despite increasing evidence in the literature indicating an association between inherited thrombophilias and adverse obstetric outcomes, doubts remain whether thrombophilic patients with venous thromboembolism present poorer maternal and neonatal outcomes than thrombophilic patients without venous thromboembolism. In this retrospective, observational and comparative study, 66 pregnant women with inherited thrombophilias, including 33 with venous thromboembolism and 36 without thromboembolism, were investigated. The main end-points analyzed were severe pre-eclampsia, placental abruption, fetal growth restriction, stillbirth, preterm delivery, and maternal hemorrhagic complications. The congenital thrombophilias included in this study were factor V Leiden (FVL), prothrombin G20210A mutation, C677T mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, protein S deficiency, protein C deficiency, and antithrombin deficiency. The two groups were similar in terms of population characteristics. The frequency of maternal and fetal/neonatal complications was similar in the two groups: severe pre-eclampsia (P=0.097), placental abruption (P=0.478), fetal growth restriction (P=0.868), stillbirth (P=0.359), preterm delivery (P=0.441), and maternal hemorrhagic complications (P=0.478). This study concluded that venous thromboembolism in thrombophilic patients does not worsen maternal or neonatal outcomes when compared to thrombophilic patients without venous thromboembolism.
135

Trombofilias maternas hereditárias com e sem tromboembolismo venoso: resultados maternos e neonatais / Maternal inherited thrombophilias with or without venous thromboembolism: maternal and neonatal outcomes

André Luiz Malavasi Longo de Oliveira 06 July 2010 (has links)
O objetivo do presente estudo foi avaliar a diferença de resultados maternos e neonatais em gestações complicadas por trombofilias hereditárias em pacientes com e sem tromboembolismo venoso. Apesar do aumento de evidências, na literatura, sobre a associação de trombofilias congênitas e resultados obstétricos adversos, há ainda dúvida se pacientes trombofílicas com tromboembolismo venoso apresentam resultados maternos e neonatais piores que as pacientes trombofílicas sem tromboembolismo venoso. O estudo analisou 66 gestantes com trombofilias hereditárias, de forma retrospectiva observacional e comparativa, das quais 33 apresentavam tromboembolismo venoso e 36 o não apresentavam. Os principais desfechos relacionados a resultados maternos e neonatais adversos foram: pré-eclâmpsia grave, descolamento prematuro de placenta, restrição de crescimento fetal, natimortalidade, prematuridade e complicações hemorrágicas maternas. As trombofilias congênitas incluídas no estudo foram o fator V de Leiden (FVL), mutação da protrombina G20210A, mutação C677T do gene da 5,10-metilenotetrahidrofolato redutase (MTHFR), deficiência de proteína S, deficiência de proteína C e deficiência de antitrombina. Ambos os grupos apresentaram características populacionais similares. A ocorrência de complicações maternas e fetais/neonatais foi similar nos dois grupos: pré-eclâmpsia grave (P=0,097), descolamento prematuro de placenta (P=0,478), restrição de crescimento fetal (P=0,868), natimortalidade (P=0,359), prematuridade (P=0,441) e complicações hemorrágicas maternas (P=0,478). Este estudo concluiu que a presença de tromboembolismo venoso em gestantes com trombofilia hereditária apresenta resultados maternos e neonatais semelhantes àquelas com trombofilias hereditárias sem tromboembolismo venoso. / The aim of this study was to evaluate differences in maternal and neonatal outcomes in pregnancies complicated by inherited thrombophilias between patients with and without venous thromboembolism. Despite increasing evidence in the literature indicating an association between inherited thrombophilias and adverse obstetric outcomes, doubts remain whether thrombophilic patients with venous thromboembolism present poorer maternal and neonatal outcomes than thrombophilic patients without venous thromboembolism. In this retrospective, observational and comparative study, 66 pregnant women with inherited thrombophilias, including 33 with venous thromboembolism and 36 without thromboembolism, were investigated. The main end-points analyzed were severe pre-eclampsia, placental abruption, fetal growth restriction, stillbirth, preterm delivery, and maternal hemorrhagic complications. The congenital thrombophilias included in this study were factor V Leiden (FVL), prothrombin G20210A mutation, C677T mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, protein S deficiency, protein C deficiency, and antithrombin deficiency. The two groups were similar in terms of population characteristics. The frequency of maternal and fetal/neonatal complications was similar in the two groups: severe pre-eclampsia (P=0.097), placental abruption (P=0.478), fetal growth restriction (P=0.868), stillbirth (P=0.359), preterm delivery (P=0.441), and maternal hemorrhagic complications (P=0.478). This study concluded that venous thromboembolism in thrombophilic patients does not worsen maternal or neonatal outcomes when compared to thrombophilic patients without venous thromboembolism.
136

Comparison of congenital cardiac surgery techniques through the development of national and international cohorts

Deshaies, Catherine 11 1900 (has links)
Plusieurs avancées exceptionnelles ont permis à un nombre grandissant d’enfants avec pathologies cardiaques complexes d’atteindre l’âge adulte. Ainsi, plus de patients développent maintenant des complications en lien avec leur maladie ou leurs antécédents chirurgicaux. Malheureusement, en raison de nombreux obstacles limitant la recherche en cardiopathie congénitale adulte, un écart de savoir perdure et freine l’optimisation des soins. En attendant le couplage de grands registres pédiatriques et adultes facilitant l’accès aux données existantes, les projets multicentriques indépendants demeurent essentiels. Cette thèse présente deux études multicentriques de cohorte comparant des techniques opératoires couramment utilisées dans le traitement de pathologies congénitales cardiaques complexes dans le but de promouvoir la santé des patients à long terme. La première étude visait à évaluer l’impact chronique du type de procédure de Fontan sur le risque thromboembolique. Pour ce projet nord-américain, 522 patients avec connexion atriopulmonaire (21.4%), tunnel latéral (41.8%) ou conduit extracardiaque (36.8%) ont été recrutés. À l’aide d’analyses multivariées contrôlant pour la décennie opératoire et les effets variables dans le temps de l’arythmie et de la thromboprophylaxie, l’étude a conclu à un plus faible risque de complications thromboemboliques systémiques (rapport des risques instantanés [RRI] : 0.20 ; intervalle de confiance [IC] à 95% : 0.04-0.97) et combinées (RRI : 0.34 ; IC à 95% : 0.13-0.91) avec le conduit extracardiaque. Ces résultats remettent en question la croyance populaire selon laquelle cette technique serait plus thrombogène en raison d’un grand contact avec du matériel synthétique et d’un débit limité par le calibre fixe du greffon. La deuxième étude avait pour but d’investiguer, auprès de patients avec tétralogie de Fallot ou sténose pulmonaire corrigée nécessitant une implantation de valve pulmonaire, l’efficacité immédiate et l’innocuité d’une intervention concomitante sur la valve tricuspide. Pour ce projet pancanadien, 542 patients ayant subi un remplacement isolé de la valve pulmonaire (66.8%) ou une chirurgie combinée des valves pulmonaire et tricuspide (33.2%) ont été enrôlés. À l’aide d’analyses multivariées, cette étude a révélé que la chirurgie combinée était associée à une plus grande réduction du grade de régurgitation tricuspidienne qu’un remplacement isolé de la valve pulmonaire (rapport de cotes [RC] : 0.44 ; IC à 95% : 0.25-0.77) sans une augmentation des complications périopératoires (RC : 0.85 ; IC à 95% : 0.46-1.57) ou du temps d’hospitalisation (ratio du taux d’incidence : 1.17 ; IC à 95% : 0.93-1.46). Ces résultats questionnent la pertinence d’une gestion conservatrice de l’insuffisance tricuspide sévère. De plus, ils confirment qu’une procédure ciblée peut améliorer de façon sécuritaire la fuite modérée au-delà de l’effet produit par la décharge du ventricule – une stratégie potentiellement avantageuse auprès de jeunes patients déjà à haut risque de défaillance cardiaque droite. En conclusion, avec une puissance statistique plus élevée que les études précédemment publiées, ces travaux ont permis une comparaison valide et pertinente de techniques opératoires couramment utilisées en chirurgie cardiaque congénitale, ce qui influencera possiblement la pratique. Ultimement, cette thèse souligne l’importance de promouvoir la collaboration afin de répondre aux besoins émergents des patients avec pathologies congénitales cardiaques complexes. / Outstanding technical advances have made possible for a growing number of infants with complex heart disease to survive into adulthood. Consequently, more patients are now living long enough to experience late complications related to their underlying pathology or sequelae from past interventions. However, due to the inherent challenges of carrying research in adult congenital heart disease, important knowledge gaps prevent further optimization of care. Waiting on broad linkage of pediatric and adult databases to facilitate access to data, stand-alone multicenter research initiatives remain essential. The current body of work presents two multicenter cohort studies which were designed to help improving the long-term health of patients with complex heart disease through a comparison of common operative techniques. The first study sought to evaluate the chronic impact of Fontan surgery type on the thromboembolic risk. This North American cohort enrolled 522 patients with univentricular palliation consisting of an atriopulmonary connection (21.4%), lateral tunnel (41.8%) or extracardiac conduit (36.8%). In multivariable analyses stratified by surgical decade and controlling for the time-varying effects of atrial arrhythmias and thromboprophylaxis, extracardiac conduits were independently associated with a lower risk of systemic (hazard ratio [HR]: 0.20 vs. lateral tunnel; 95% confidence interval [CI]: 0.04-0.97) and combined (HR: 0.34 vs. lateral tunnel; 95% CI: 0.13-0.91) thromboembolic events. These results cast doubt on the widely held notion that extracardiac conduits are potentially more thrombogenic than lateral tunnels by virtue of greater exposure to synthetic material and relative flow restriction through a fixed pathway. The second study investigated, in patients with repaired tetralogy of Fallot or equivalent disease undergoing a first pulmonary valve implant, the early effectiveness and safety of concomitant tricuspid valve intervention. This pan-Canadian cohort included 542 patients who underwent isolated pulmonary valve replacement (66.8%) or combined pulmonary and tricuspid valve surgery (33.2%). In multivariable analyses, combined surgery was associated with a greater reduction in tricuspid regurgitation grade than isolated pulmonary valve replacement (odds ratio [OR]: 0.44; 95% CI: 0.25-0.77) without an increase in early adverse events (OR: 0.85; 95% CI: 0.46-1.57) or hospitalization time (incidence rate ratio: 1.17; 95% CI: 0.93-1.46). These results strongly question the appropriateness of conservative management of severe tricuspid regurgitation at the time of pulmonary reintervention. Furthermore, they confirm that concomitant tricuspid valve intervention can safely improve moderate insufficiency beyond the effect of right ventricular offloading – a strategy likely worthwhile to adopt in a population of young adults already at high risk of right heart failure. In conclusion, with higher statistical power than previously published studies, the presented body of work allowed for a valid comparison of common surgical techniques used in congenital cardiac care, which will likely impact current practices. Ultimately, this thesis underlines the importance of fostering collaboration in order to meet the emerging health needs of patients with complex heart disease.
137

Detecting plasma biomarkers in patients with venous thromboembolism using proximity extension assay / Detektion av plasmabiomarkörer hos patienter med venös tromboembolism med proximity extension assay

Johansson, Emil January 2023 (has links)
Venös tromboembolism (VTE) inkluderar både djup ventrombos (DVT) och lungemboli (PE) och är en vanlig och komplex kardiovaskulär sjukdom med allvarliga kortsiktiga och långsiktiga komplikationer. I dagens kliniska praxis skulle diagnoseringen av VTE gynnas av en plasmaproteinpanel som antingen kan utesluta fall av akut VTE på egen hand eller komplettera den nuvarande biomarkören D-dimer, som i sig är begränsad av låg specificitet. På grund av den höga återfallsfrekvensen och de allvarliga post-syndromen skulle en plasmaproteinpanel som kan bedöma risken för återkommande VTE underlätta för kliniker i efterbehandlingsbeslut. Mot denna bakgrund syftade denna studie till att föreslå två separata plasmaproteinpaneler, en för att utesluta akuta VTE-patienter och en annan för att bedöma risken för återkommande VTE. Med 1463 unika plasmaproteiner screenades plasmaproteomet hos 194 individer från två undergrupper av venös tromboembolism-biomarkörstudien (VEBIOS), närmare bestämt VEBIOS ER och VEBIOS Coag, med hjälp av proximity extension assay (PEA). Både genuttryck (DE) -analys och maskininlärning (ML) -algoritmer användes för att identifiera signifikanta respektive viktiga proteiner. För akut VTE identifierades 10 signifikanta proteiner genom DE, samt en panel bestående av fem proteiner tillsammans med D-dimer hade tillsammans en area under kurvan (AUC) på 0,97 genom ML. För återkommande VTE identifierades inga signifikanta proteiner och den bästa proteinpanelen hade en AUC på 0,62. Vissa av dessa proteiner har tidigare rapporterats vara associerade med VTE och vissa inte, vilket resulterar i ortogonal validering eller påvisande av en potentiell ny biomarkör. Sammanfattningsvis hittades flera intressanta plasmaproteiner som potentiellt skulle kunna användas för att utesluta fall av akut VTE. GP1BA och S100A12 var särskilt intressanta då de var återkommande som högt ansenliga enligt DE och ML. Resultaten från denna studie kommer förhoppningsvis bidra till forskningen gällande förbättrad diagnos av VTE-patienter genom användning av plasmaproteinmarkörer och argumentationen för ytterligare undersökningar för dessa identifierade plasmaproteiner. / Venous thromboembolism (VTE) is a common and complex cardiovascular disorder with serious short- and long-term complications, comprising both deep vein thrombosis (DVT) and pulmonary embolism (PE). In current clinical practice, diagnosis of acute VTE would greatly benefit from a plasma protein panel that can exclude cases of VTE on its own or complement the current biomarker, D-dimer, which is limited by low specificity. Because of the high recurrence rate and serious post-syndromes, a protein panel that can assess the risk of VTE recurrence would help clinicians in post-treatment decision-making. Hence, this study sought out to propose two separate plasma biomarker panels, one to exclude acute VTE patients and another to risk-assess VTE recurrence.  To accomplish this, 1463 unique plasma proteins were used to investigate the plasma proteome of 194 individuals from two subgroups of the venous thromboembolism biomarker study (VEBIOS), specifically VEBIOS ER and VEBIOS Coag, using proximity extension assay (PEA). Both differential expression (DE) analysis and machine learning (ML) algorithms were used to find significant and important proteins respectively. For acute VTE, 10 significant proteins were identified through DE, and a panel of five proteins together with D-dimer had together an area under the curve (AUC) of 0.97 through ML. For VTE recurrency, no significant proteins were identified, and the best protein panel had an AUC of 0.62. Some of these proteins have previously been reported as associated to VTE and some not, resulting in some orthogonal validation or novelty. In summary, several interesting plasma proteins were found that could potentially be used to exclude cases of VTE in an acute setting. GP1BA and S100A12 were particularly interesting as they performed well in both DE and ML. The results in this study will hopefully aid the research of improving diagnosis of VTE patients using plasma biomarkers, strengthening the claim and further investigations for these identified plasma proteins.

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