Orientador: Marcone Lima Sobreira / Resumo: A insuficiência renal crônica (IRC) é uma desordem metabólica de instalação lenta e irreversível muito prevalente. Estima-se que existam cerca de 1,2 a 1,5 milhão de pacientes no Brasil. Condições clínicas como: diabetes mellitus, hipertensão arterial sistêmica, lúpus, infecções, traumas são os principais causadores da IRC. Para a realização da hemodiálise são utilizados acessos temporários como os cateteres, ou confeccionada um acesso definitivo que são as fístulas arteriovenosas (FAVs), que podem apresentar complicações como trombose, hipertensão venosa, roubo de fluxo ou infecções, as quais podem contribuir para a perda do acesso. Para análise da condição funcional da FAV, pode-se utilizar o conhecimento da pressão intra-acesso (PIA) venosa e arterial, que podem ser correlacionadas com parâmetros hemodinâmicos como pressão venosa (PV) e o fluxo de sangue (QB) fornecidos durante a hemodiálise pela máquina. Neste estudo prospectivo, serão aferidas as PIAs dos pacientes do setor de hemodiálise do Hospital das Clínicas da Faculdade de Medicina de Botucatu/UNESP que possuem FAV com o objetivo de se identificar sinais indicativos de estenose subclínica, correlacionando-os com os parâmetros ultrassonográficos (velocidade de pico sistólico, velocidade diastólica final e volume de fluxo). O método utilizado baseia-se no isolamento da pressão do sistema e do dialisador visando aferir a pressão estática e coleta dos valores de PV e do QB. Esses dados serão colocados em planilha Excel... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-06-19T11:21:12Z No. of bitstreams: 1 andersontavaresrodrigues.pdf: 12102128 bytes, checksum: ad04f5fdd01e1041a5459207d8137ad5 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-06-29T12:18:45Z (GMT) No. of bitstreams: 1 andersontavaresrodrigues.pdf: 12102128 bytes, checksum: ad04f5fdd01e1041a5459207d8137ad5 (MD5) / Made available in DSpace on 2017-06-29T12:18:45Z (GMT). No. of bitstreams: 1 andersontavaresrodrigues.pdf: 12102128 bytes, checksum: ad04f5fdd01e1041a5459207d8137ad5 (MD5) Previous issue date: 2015-03-20 / A doença renal crônica (DRC) é uma enfermidade de grande morbimortalidade. A hemodiálise periódica é o método mais amplamente utilizado na manutenção da sobrevida dos pacientes com DRC. No tratamento hemodialítico é necessário uma via de um acesso vascular, sendo o padrão-ouro é a fístula arteriovenosa (FAV). As principais complicações da FAV são a falência do acesso e consequente maior morbimortalidade. Os objetivos do trabalho são: 1) avaliar a taxa de sucesso nas FAV confeccionadas pelo nefrologista; e 2) identificar as variáveis clínicas, laboratoriais e demográficas que impactam na patência da FAV. Método: Estudo de coorte retrospectiva caracterizado pelo exame de prontuários de pacientes com DRC e que realizaram confecção de FAV pelo nefrologista. Foram incluídos os prontuários de 101 pacientes, totalizando 159 procedimentos entre junho de 2010 e junho de 2013. Resultados: Das FAV realizadas, 124 (78%) apresentaram patência imediata e 110 (62,9%) apresentaram patência tardia. Das variáveis estudadas somente a hemoglobina mostrou relação com a patência tardia da FAV (p=0,05). Pressão arterial elevada no momento da cirurgia se associou com redução do número de procedimentos por paciente com p=0,001. FAV distais se associaram a maior número de procedimentos por paciente com p=0,03. Adicionalmente, observou-se que o nosso índice de sucesso de patência da FAV apresentou índices compatíveis com os da literatura por outros nefrologistas e cirurgiões vasculares. Conclusão: Manutenção de hemoglobina nas faixas recomendadas impactam favoravelmente na patência tardia da FAV, pressão arterial elevada no momento da cirurgia associou-se com menor número de procedimentos a que o paciente é submetido. Os procedimentos distais se associaram a maior número de procedimentos por paciente, enquanto os proximais são mais frequentes em pacientes com 2 acessos, indicando sua utilização principalmente na falha dos acessos distais. / Chronic kidney disease (CKD) is an illness of high morbidity and mortality. The periodic hemodialysis is the most widely used method in maintaining the survival of patients with CKD. In hemodialysis is needed a vascular access, and the gold standard is the arteriovenous fistula (AVF). The main complications of AVF are the failure of access and consequent higher mortality. The objectives are: 1) to evaluate the success rate in AVF made by a nephrologist; and 2) to identify clinical, laboratory and demographic variables that impact the AVF patency. Method: Retrospective cohort study characterized the examination records of patients with CKD who underwent construction of AVF by a nephrologist. The medical records of 101 patients were included, totaling 159 procedures between June 2010 and June 2013. Results: Of AVF performed, 124 (78%) had immediate patency and 110 (62.9%) had late patency. Of the variables studied only hemoglobin was related to the late patency of AVF (p = 0.05). High blood pressure at the time of surgery was associated with fewer procedures per patient with p = 0.001. Distal AVF associated with a major number of procedures per patient with p = 0.03. Additionally, it was observed that our AVF patency success rate compatible with the indexes presented in the literature by other nephrologists and vascular surgeons. Conclusion: hemoglobin maintenance at the recommended tracks impact favorably on late patency of the AVF, high blood pressure at the time of surgery was associated with fewer procedures which the patient is submitted. The distal procedures associated with a major number of procedures per patient, while the proximal are more frequent in patients with 2 accesses, indicating its use mainly in the failure of distal access.

Les anévrysmes se développant au niveau des fistules artério-veineuses (FAV), représentent une complication rare mais potentiellement mortelle dont la physiopathologie reste inexplorée. Jusqu’à présent la pratique courante était de les remplacer par un segment prothétique. Nous avons proposé un nouveau traitement chirurgical consistant en une anévrysmorraphie veineuse renforcée extérieurement par une exoprothèse. Notre premier objectif a été de rapporter les résultats à un an de cette nouvelle technique. Dans un second temps nous avons perfusé ex vivo des veines saphènes humaines renforcées par la même exoprothèse dans des conditions hémodynamiques de shear stress (SS) artériel en faisant varier la pression. L’analyse morphologique a montré le développement d’une hyperplasie intimale dans la veine sans et avec exoprothèse à haute pression. L’analyse des gènes et des protéines impliqués dans le remodelage vasculaire n’a pas montré de différence entre la veine nue et la veine renforcée mais nous a permis de mieux caractériser le rôle du SS et de la pression dans le mécanisme de l’artérialisation veineuse. Notre troisième objectif a été de décrire le remodelage anévrysmal des FAV. A partir d’une tissuthèque constituée d’échantillons de veines prélevées chez les patients opérés, nous avons comparé la veine artérialisée anévrysmale à la veine non artérialisée non anévrysmale. Les métalloprotéinases et leurs inhibiteurs participent activement à ce remodelage. Les anévrysmes régulièrement ponctionnés ont un profil inflammatoire qui influence la nature de ce remodelage. / Aneurysm complicating arteriovenous fistula (AVF) is a rare but potentially life-threatening complication. To date, its pathobiology remains unexplored and prosthetic replacement constitutes the conventionnal treatment. We have proposed a new surgical technique consisting in a venous aneurysmorraphy reinforced by an exoprosthesis. Our first goal was to evaluate the one-year results in terms of patency and aneurysm recurrence. Secondly, we have studied the impact of the exoprosthesis on human saphenous veins perfused ex vivo and submitted to different flow conditions consisting in an arterial shear stress (SS) in association with a low or a high pressure setting. Morphological analysis revealed an intimal hyperplasia in veins with and without exoprosthesis under high pressure. Analysis of the proteins and genes involved in the vascular remodeling did not showed an exoprosthesis effect but allowed us to better decipher the selective role played by SS and pressure in the arterialization process. Thirdly, we have collected tissue samples from patients operated and compared aneurysmal arterialized veins to non-aneurysmal non-arterialized veins. Metalloproteinases and their inhibitors actively participate in the remodeling. In aneurysms frequently cannulated inflammation influence the remodeling process.

<p>UVOD: Komplikacije terminalne bubrežne isuficijencije (TBI) kada se jačina glomerularne filtracije (JGF) smanji ispod 10 mL/min moguće je lečiti jedino hroničnom dijalizom ili transplantacijom bubrega tj. nadoknadom potpuno ili delimično izgubljene bubrežne funkcije. Uz blagovremenu edukaciju bolesnika o progresivnom toku hronične bubrežne bolesti, mogućnostima dijaliznog tretmana i transplantacije bubrega, treba na vreme obezbediti stalni funkcionalni vaskularni pristup za hemodijalizu (HD) hirur&scaron;kom intervencijom kreiranja arteriovenske fistule (AVF), po mogućnosti najmanje 6 meseci pre anticipiranog započinjanja HD, jer je za njenu maturaciju potrebno 4 do 6 nedelja. Primarna AVF je op&scaron;tepreporučeni najbolji stalni vaskularni pristup za bolesnike kod kojih se planira hemodijaliza. Najče&scaron;ći razlog za disfunkciju vaskularnog pristupa za hemodijalizu su u 80% slučajeva trombozne komplikacije, koje se u 90% slučajeva javljaju na venskom segmentu AVF i posledica su progresivne venske neointimalne hiperplazije. Pored histolo&scaron;kih karakteristika zida venskog krvnog suda i hemodinamskih uslova, u etiopatogenezi ovog &raquo;adaptivnog odgovora&laquo; vrlo značajnu ulogu igraju endotel i ostale komponente hemostaznog sistema (trombocitna, koagulaciona i fibrinolizna), imunolo&scaron;ki i citolo&scaron;ki činioci i genetski faktori. Prevencija nastanka rane tromboze vaskularnog pristupa za hemodijalizu kod bolesnika sa TBI je moguća primenom antitromboznih lekova, tj. antitrombocitne ili antikoagulantne terapije. CILJ: Proceniti efikasnost primenjenih antitromboznih lekova (tiklopidina i nadroparin-kalcijuma) u prevenciji nastanka rane tromboze/afunkcionalnosti AVF za hemodijalizu za vreme njene maturacije unutar 6 nedelja od kreiranja u bolesnika sa TBI. Ispitati nivo biomarkera hemostaznog sistema i markere trombofilije u bolesnika sa TBI pre kreiranja AVF u cilju dopune uzroka nastanka rane tromboze/afunkcionalnosti arteriovenskih fistula za hemodijalizu. Ispitati učestalost trombofilije i njen uticaj na funkcionalnost AVF i uporediti efikasnost primenjenih preventivnih režima između bolesnika sa i bez trombofilije. MATERIJAL I METODE: U ispitivanje su uključene osobe oba pola sa prethodno postavljenom dijagnozom TBI kod kojih nisu postojale kontraindikacije za planirno hirur&scaron;ko kreiranje prvog stalnog vaskularnog pristupa za hemodijalizu u vidu autologne arteriovenske fistule (AAVF). Nakon hirur&scaron;kog kreiranja radiocefalične arteriovenske fisule u distalnoj trećini podlaktice nedominantne ruke (89/121), intermedijalne (4/121) ili proksimalne (28/121) AAVF u studiju je uključen 121 ispitanik, koji su u cilju procene uticaja različitih antitromboznih lekova na sprečavanje nastanka rane tromboze fistula za hemodijalizu kod bolesnika sa TBI ispitanici su podeljeni u 3 grupe: Grupa I, kontrolna; 40 ispitanika koji nakon kreiranja AVF nisu dobijali antitromboznu terapiju, Grupa II; 42 ispitanika kod kojih je dan nakon kreiranja AVF započeta primena antitrombocitnog leka iz grupe tienopiridina, Ticlodix&reg; (ticlopidin) tbl a 250 mg, 2 x &frac12; tbl dnevno tokom 6 nedelja i Grupa III; 39 ispitanika kod kojih je dan nakon kreiranja AVF započeta subkutana primena antikoagulantnog leka iz grupe niskomolekularnih heparina, Fraxiparine&reg; (nadroparin-kalcijum) 2850 anti Xa i.j. (0.3 ml) dnevno tokom 6 nedelja. Jednokratno određivanje laboratorijskih parametara pokazatelja bubrežne funkcije, metabolizma glukoze i hroničnog zapaljenja, funkcionalnosti hemostaznog sistema, trombofilnih markera i genskog polimorfizma vr&scaron;eno je unutar dve nedelje pre hirur&scaron;kog kreiranja AAVF. Kriterijum za utvrđivanje ishoda uticaja antitrombozne terpije predstavlja maturacija AVF koja je definisana kao uspe&scaron;na ako je započeto sprovođenje efikasne hemodijalize najranije 6 nedelja nakon njenog hirur&scaron;kog kreiranja po proceni nadležnog nefrologa. Dijagnoza prisustva tromboze AVF postavljena je od strane nadležnog vaskularnog hirurga/nefrologa fizikalnim pregledom tokom njene maturacije, koji je podrazumevao inspekciju, palpatorno utvrđivanje odsustva karakterističnog trila i auskultatornih karakteristika protočnosti AVF ili ultarsonografskim pregledom od strane radiologa. REZULTATI: Između ispitivanih grupa u odnosu na broj tromboziranih/ afunkcionalnih AVF tokom njene maturacije (12/40 vs. 4/42 vs. 5/39; P=0.033), ustanovljena je značajna statistička razlika kao i poređenjem broja tromboziranih/afunkcionalnih AVF tokom sazrevanja u kontrolnoj grupi u odnosu na grupu ispitanika (objedinjene Grupe II i Grupa III) koja je primala antitromboznu profilaksu (12/40 vs. 9/81; P=0.009). Daljom analizom ispitivanih grupa, utvrđena je statistički značajna razlika u broju tromboziranih/afunkcionih AV fistula između kontrolne Grupe I i Grupe II (P=0.019). Testiranjem razlike u broju tromboziranih/ afunkcionalnih AVF između ispitanika kontrolne Grupe I i Grupe III nije dobijena statistički značajna razlika, kao ni između Grupe II i Grupe III. Zastupljenost broja tromboziranih/afunkcionalnih distalnih AVF za vreme njihove maturacije (12/33 vs 2/31 vs. 3/24; P=0.008) se između ispitivanih grupa značajno statistički razlikovala kao i zastupljenost tromboziranih/afunkcionalnih distalnih AVF tokom sazrevanja u kontrolnoj grupi u odnosu na grupu ispitanika koja je primala antitromboznu profilaksu (12/34 vs. 5/55; P=0.002). Testiranjem statističke razlike u broju tromboziranih/afunkcionalnih distalnih AVF između ispitanika kontrolne Grupe I i Grupe II utvrđena je statistički značajna razlika (P=0.005), dok između Grupe I i Grupe III (P=0.051), kao ni između Grupe II i Grupe III (P=0.439) nije dobijena statistički značajna razlika. Između podgrupa ispitanika kod kojih je do&scaron;lo do tromboze/afunkcionalnosti AVF 21/121 (17.35%) i podgrupe ispitanika sa funkcionalno maturiranom AVF 90/121 (82.64%), značajna statistička razlika ispitanih hemostaznih parametara je bila prisutna u vrednostima agregabilnosti trombocita uz kolagen kao induktor (59.33&plusmn;33.1 vs. 75.04&plusmn;29.6; P=0.033). Značajna statistička razlika je zabeležena i u zastupljenosti sledećih trombofilnih markera: deficita PC (3/21 vs. 3/100; P=0.030), APC-R (4/21 vs. 5/100; P=0.026), prisustva antifosfolipidnih ACL IgM antitela (1/21 vs. 0/100; P=0.028), heterozigotnog polimorfizma FV G1691A (3/21 vs. 3/100; P=0.03) i homozigotne mutacije gena FII G20210A (1/21 vs. 0/100; P=0.028), između podgrupa bolesnika sa tromboziranom afunkcionalnom i funkcionalnom AVF. Takođe je značajna statistička razlika između podgrupa bolesnika kod kojih je do&scaron;lo tromboze/afunkcionalnosti AVF i podgrupe ispitanika sa funkcionalno maturiranom AVF bila prisutna u odnosu na postojanje ranijih tromboza (23/21 vs 19/100; P=0.000) kao i zastupljenosti izolovanih venskih tromboza (9/21 vs. 2/100; P=0.000). Prediktivni potencijal pojedinačnih parametara za maturaciju AVF ispitan je univarijantnom logističkom regresionom analizom. Prilikom ispitivanja uticaja pojedinačnih parametara na maturaciju fistule, zapazili smo da su ispitanici koji su primali antitromboznu terapiju imali 3 puta veću &scaron;ansu za funkcionalno maturiranu AVF [OR 3.45 (1.3-9.03)] u odnosu na bolesnike bez terapije. Ispitanici koji su imali prethodne tromboze su imali vi&scaron;estruko povi&scaron;en rizik [OR 6.92 (2.51-19.06)] za nastanak tromboze/afunkcionalnost AVF tokom maturacije. Prilikom ispitivanja uticaja pojedinačnih parametara na rizik od pojave tromboze/afunkcionalnosti distalne AVF, zapažamo da primena antitrombozne terapije [OR 5.4 (CI 1.7 - 17.35)] petostruko snižava rizik za nastanak tromboze/ afunkcionalnosti distalne AVF, odnosno da primena antitrombozne terapije petostruko povećava &scaron;ansu za adekvatnu maturaciju distalne AVF. Ispitanici koji su imali aterosklerotske KVB [OR 0.32 (0.1-0.98)] i ranije tromboze [OR 0.14 (0.04-0.44)] su imali za 68% i 86% manju verovatnoću za adekvatnu maturaciju distalne AVF (334). Trombofilija je bila prisutna u 59/121 (48.8%) ispitanika. U odnosu na markere aktivacije koagulacione komponente hemostaznog sistema i inflamatorne pokazatelje, između podgrupa ispitanika sa ili bez trombofilije statistički značajna razlika je bila prisutna u vrednostima koncentracije FVIII (170.35&plusmn;103.97 vs. 235.26&plusmn;124.80; P=0.02) i odnosa trombociti/limfociti (181&plusmn;64.58 vs. 148.11&plusmn;66.15; P=0.026). U odnosu na lokalizaciju AVF, u podgrupi ispitanika sa trombofilijom i tromboziranom/ afunkcionalnom AVF, njih 8/11 su pripadale distalnim AVF, 3/11 proksimalnim AVF, dok je u podgrupi ispitanika bez trombofilije i tromboziranom/afunkcionalnom AVF, njih 9/10 imalo distalnu, a 1/10 proksimalnu AVF. U grupi bolesnika sa trombofilijom nije zabeleženo prisustvo statistički značajne razlike u efikasnosti primenjenih antitromboznih režima merene učestalo&scaron;ću tromboza/afunkcionalnosti AVF u odnosu na bolesnike sa trombofilijom koji nisu primali antitromboznu terapiju (5/19 vs. 2/18 vs. 4/22; P=0.493). U grupi ispitanika bez trombofilije utvrđeno je postojanje statistički značajne razlike u učestalosti tromboza/afunkcionalnosti AVF između grupe sa i bez primene antitromboznih lekova kako u ukupnom broju tromboziranih/afunkcionalnih AVF (7/21 vs. 2/24 vs. 1/17; P=0.030). Iako je zastupljenost tromboza/afunkcionalnosti AVF u bolesnika sa kombinovanom trombofilijom če&scaron;ća u odnosu na ispitanike koji su imali drugu vrstu ili uop&scaron;te nisu imali trombofiliju (6/18 vs. 15/103; P=0.052), ona nije dostigla statistički značajnu vrednost. ZAKLJUČAK: Profilaktička primena antitromboznih lekova (tiklopidina i nadroparin-kalcijuma) smanjuje učestalost pojave rane tromboze i pojavu primarne nefunkcionalnosti AVF za hemodijalizu tokom njene maturacije. Primena antitrombozne terapije petostruko snižava rizik za nastanak tromboze/ afunkcionalnosti distalne AVF tokom njene maturacije. Bolesnici koji su imali prethodne tromboze imaju vi&scaron;estruko povi&scaron;en rizik za nastanak tromboze AVF tokom njene maturacije. Kod bolesnika koji su imali aterosklerotske KVB i ranije tromboze verovatnoća za adekvatnu maturaciju distalne AVF je niža za 68% , odnosno 86%. U na&scaron;em istraživanju nije utvrđeno postojanje superiornosti antikoagulantne u odnosu na antitrombocitnu profilaksu tj. oba primenjena režima su bila podjednako efikasna. U terminalnoj bubrežnoj insuficijenciji prisutan je značajan poremećaj funkcionalnosti hemostaznog sistema koji se očituje u disfunkciji endotela i poremećenoj (sniženoj) funkcionalnosti trombocita, prisustvu prokoagulantnog stanja koje se manifestuje povi&scaron;enom trombinskom aktivno&scaron;ću, povi&scaron;enom koncentracijom činilaca koagulacije i smanjenom fibrinoliznom aktivno&scaron;ću. Če&scaron;ća zastupljenost ukupnih ranijih tromboza (arterijskih i venskih), če&scaron;ća zastupljenost izolovanih venskih tromboza i učestalije prisustvo trombofilije prezentovano deficitom PC, prisustvom rezistencije na APC, prisusustvom antifosfolipidnih antikardiolipinskih antitela IgM, heterozigotnog polimorfizma FV G1691A, homozigotne mutacije FII G201210A i niža vrednost agregabilnosti trombocita uz kolagen kao induktor su markeri koji su u na&scaron;em ispitivanju signifikantno če&scaron;će zastupljeni kod ispitanika sa trombozom/ afunkcijom AVF za hemodijalizu tokom njenog sazrevanja. Trombofilija je prisutna kod 48.8% bolesnika saTBI, ali na&scaron;im ispitivanjem nije utvrđen njen uticaj na nastanak rane tromboze/afunkcionalnosti AVF izuzev u grupi bolesnika sa kombinovanom trombofilijom. Mali broj krvarećih komplikacija u na&scaron;oj studiji ukazuje na bezbednost primenjenog preventivnog režima. Na osnovu dobijenih rezultata može se preporučiti profilaktička primena tiklopidina ili nadroparin-kalcijuma u preventivnim dozama kod bolesnika sa TBI neposredno nakon kreiranja AVF. Primenu profilakse tromboznih komplikacija kod bolesnika sa novokreiranom AVF preporučujemo posebno kod bolesnika koji su imali prethodne tromboze i/ili kliničke manifestacije aterosklerotskih kardiovaskularnih bolesti.</p> / <p>INTRODUCTION: Complications in end stage renal disease (ESRD) when the glomerular filtration rate (GFR) decreases below 10mL/min can only be treated by chronic dialysis or kidney transplant ie. total or partial renal replacement therapy. With prompt education of the patient regarding the progressive course of the chronic kidney disease, possibilities of dialysis treatment and kidney transplantation, the patient should timely be granted permanent functional vascular hemodialysis (HD) access through surgical intervention by creating arteriovenous fistula (AVF), preferably at least 6 months prior to the anticipated start of HD, as period for its maturation is between 4 and 6 weeks. Primary AVF is the generally best recommended permanent vascular access for patients planned for dialysis. The most common reason for dysfunction of the vascular access for hemodialysis are thrombotic complications in 80% of the cases, 90% of which appear in the venous segment of AVF as the consequence of progressive venous neointimal hyperplasia. Beside the histological characteristics of the venous blood vessel wall and hemodynamic conditions, in the etiopathogenesis of this &ldquo;adaptive answer&rdquo;, endothel and other components of the hemostatic system (platelet, coagulation and fibrinolysis), immunological and cytological components as well as genetic factors play a very important role. Prevention of occurrence of early thrombosis of vascular access for hemodialysis in patients with ESRD is possible by treatment with antithrombotic drugs, ie. antiplatelet or anticoagulant therapy. OBJECTIVE: Estimate the efficiency of applied antithrombotic drugs (ticlopidine and nadroparincalcium) in prevention of occurrence of early thrombosis/dysfunction of AVF for hemodialysis during its time of maturation within the 6 week period. Examine the level of biomarkers of the hemostatic system and thrombophilic markers in patients with ESRD before the creation of AVF with the goal of finding additional causes of occurrence of early thrombosis/dysfunction of arteriovenous fistula for hemodialysis. Determine the incidence of thrombophilia and its impact on the functionality of AVF and compare the efficiency of applied preventive regimen between patients with and without thrombophilia. MATERIAL AND METHODS: The study included persons of both sexes with previously established diagnosis of ESRD in which there were no contraindications for the planned surgical creation of the first permanent vascular access for hemodialysis in the form of autologous arteriovenous fistula (AAVF). After the surgical creation of the radiocephalic arteriovenous fistula in the distal third of the forearm of the non-dominant hand (89/121), intermedial (4/121) or proximal (28/121) AAVF, the total number of 121 patients were included in the study and divided into three groups in order to estimate the influence of different antithrombotic drugs in prevention of early thrombosis for hemodialysis in patients with ESRD: Group I, control; 40 subjects which did not receive antithrombotic therapy after the creation of AVF, Group II; 42 subjects which started receiving an antithrombotic drug from the tienopiridine group, Ticlodix&reg; (ticlopidine) 2 x &frac12; of 250mg tbl, daily, during the period of 6 weeks, after the creation of AVF, and Group III; 39 subjects which started subcutaneously receiving a drug from the low-molecular weight herapin group, Fraxiparine&reg; (nadroparine-calcium) 2850 anti Xa i.j. (0.3 ml) daily, during the period of 6 weeks. One-time determination of laboratory parameters and renal function, glucose metabolism and chronic inflammation, hemostatic system functionality, thrombophilic markers and gene polymorphism was performed within two weeks prior to surgical creation of AAVF. The criteria for determining the outcome of the impact of antithrombotic therapy is the maturation of AVF, which is defined as successful if the implementation of effective hemodialysis started at least 6 weeks after its creation, where the effectiveness of hemodialysis is estimated by a competent nephrologist. The diagnosis of the presence of AVF thrombosis was set by a competent vascular surgeon/nephrologist through physical examination during its maturation, which included inspection, palpatory determination of absence of the characteristic thrill and auscultatory characteristics of the flow of AVF, or by ultrasonographic examination by the radiologist. RESULTS: Between the groups in terms of number of thrombosed/dysfunctional AVF during its maturation (12/40 vs. 4/42 vs. 5/39, P = 0.033), a significant statistical difference was established, as well as by comparing the number of thrombosed/dysfunctional AVF during maturation in the control group compared to the group of respondents (unified Group II and Group III) which received antithrombotic prophylaxis (12/40 vs. 9/81, P = 0.009). Through further analysis of the examined groups, a statistically significant difference was observed in the number of thrombosed/dysfunctional AV fistula between the control Group I and Group II (P = 0.019). There was no statistically significant difference noticed in the numbers of thrombosed/dysfunctional AVF between the subjects in the control Group I and Group III, as well as between Group II and Group III. Presence of the number of thrombosed/dysfunctional distal AVF during their maturation (12/33 vs 2/31 vs. 3/24, P = 0.008) between the groups statistically significantly varied, as well as the presence of the number of thrombosed/dysfunctional distal AVF during the maturation in the control group as compared to the group of subjects who received antithrombotic prophylaxis (12/34 vs. 5/55; P=0.002). By testing statistical differences in the number of thrombosed/dysfunctional distal AVF between the subjects in the control Group I and Group II a statistically significant difference (P = 0.005) was established, while there was no statistically significant difference between Group I and Group III (P = 0.051), nor between Group II and Group III (P = 0.439). Among the subgroup of patients with thrombosis/dysfunction of AVF 21/121 (17.35%) and the subgroup of subjects with functionally maturated AVF 90/121 (82.64%), a statistically significant difference of the examined hemostasis parameters was present in the values of platelet aggregation with collagen as the inducer (59.33 &plusmn; 75.04 vs. 33.1 &plusmn; 29.6; P = 0.033). A significant statistical difference was recorded in the presence of the following thrombophilic markers: deficit of PC (3/21 vs. 3/100; P = 0.030), APC-R (4/21 vs. 5/100; P = 0.026), the presence of antiphospholipid ACL IgM antibodies ( 1/21 vs. 0/100; P = 0.028), heterozygous FV G1691A polymorphism (3/21 vs. 3/100; P = 0.03) and homozygous gene mutation FII G20210A (1/21 vs. 0/100; P = 0.028), between the subgroups of patients with thrombosed/dysfunctional and functional AVF. There also was a significant statistical difference between the groups of patients which encountered thrombosis/dysfunction of AVF and subgroups of subjects with functional maturated AVF in relation to the existence of previous thrombosis (23/21 vs. 19/100; P = 0.000) and the presence of isolated venous thrombosis (9/21 vs. 2/100; P = 0.000). Predictive potential of individual parameters for AVF maturation was tested by univariate logistic regression analysis. During the examination of the influence of individual parameters on fistula maturation, we observed that subjects who received antithrombotic therapy were 3 times more likely to develop functionally maturated AVF [OR 3.45 (1.3-9.03)] as compared to subjects who did not receive any treatment. Subjects which previously had thrombosis had a multiple times increased risk [OR 6.92 (2:51 to 19:06)] of developing thrombosis/dysfunctional AVF during its maturation. When examining the influence of individual parameters on the risk of thrombosis/dysfunction of the distal AVF, we noted that the implementation of antithrombotic therapy [OR 5.4 (CI 1.7 - 17:35)] reduced risk of thrombosis/dysfunction of the distal AVF by five times, ie. that the implementation of antithrombotic therapy increases the chance for adequate distal AVF maturation by five times. The subjects that had atherosclerotic cardiovascular diseases (CVD) [OR 0.32 (0.1-0.98)] or previous thrombosis [OR 0.14 (0.04-00.44)] had a 68% or 86% less chance for adequate distal AVF maturation (334). Thrombophilia was present in 59/121 (48.8%) patients. In relation to the markers of activation of coagulation components of the hemostatic system and inflammatory markers, among subgroups of subjects with or without thrombophilia a statistically significant difference was present in the FVIII concentration (170.35 &plusmn; 103.97 vs. 235.26 &plusmn; 124.80; P = 0.02) and the platelets/lymphocytes ratio (181 &plusmn; 64.58 vs. 148.11 &plusmn; 66.15; P = 0.026). In relation to the localization of AVF, in the subgroup of subjects with thrombophilia and thrombosed/dysfunctional AVF, 8/11 of them belonged to distal AVF, 3/11 proximal AVF, while in the subgroup of subjects without thrombophilia and thrombosed/dysfunctional AVF, had 9/10 distal and 1/10 proximal AVF. In the group of subjects with thrombophilia there was no record of the presence of statistically significant differences in the efficiency of antithrombotic regimen which was measured by the frequency of thrombosis/dysfunction of AVF as compared to subjects with thrombophilia which did not receive antithrombotic therapy (5/19 vs. 2/18 vs. 4/22, P = 0.493). In the group of subjects without thrombophilia statistically significant differences were found in the frequency of thrombosis/dysfunctions of AVF among groups with and without the use of antithrombotic drugs in the total number of thrombosed/dysfunctional AVF (7/21 vs. 2/24 vs. 1/17, P = 0.030). Although the presence of thrombosis/dysfunction of AVF in patients with combined thrombophilia was more frequent compared to those who had other types of, or did not have thrombophilia (6/18 vs. 15/103; P = 0.052), it did not reach a statistically significant value. CONCLUSION: Prophylactic use of antithrombotic drugs (ticlopidine and nadroparin-calcium) reduces the incidence of early thrombosis and the occurrence of primary AVF dysfunction for hemodialysis during its maturation. Implementation of antithrombotic therapy reduced risk of thrombosis/ dysfunction of the distal AVF during its maturation by five times. Patients who have had previous thrombosis have multiple times greater risk of AVF thrombosis during its maturation. In patients who had atherosclerotic CVD or previous thrombosis, the probability for adequate maturation of distal AVF is lower by 68% or 86%. In our study there was no evidence of superiority of anticoagulant compared to antiplatelet prophylaxis ie. both regimens were equally effective. In ESRD there is significant disarrangement of hemostatic system functionality, which is reflected in endothelial dysfunction and disturbed (reduced) platelet functionality, the presence of procoagulant condition that is manifested by elevated thrombin activity, increased levels of clotting factors and reduced fibrinolytic activity. More frequent presence of total previous thrombosis (arterial and venous), higher frequency of isolated venous thrombosis and frequent presence of thrombophilia presented by the deficit of PC, the presence of resistance to APC, presence of anticardiolipin antiphospholipid antibodies IgM, heterozygous FV G1691A polymorphism, homozygous mutation FII G201210A and lower value of collagen induced platelet aggregation are the markers in our study which are significantly more frequent in patients with thrombosis/dysfunction of AVF for hemodialysis during its maturation. Thrombophilia is present in 48.8% of patients with ESRD, however our study does not determine its impact on early thrombosis/dysfunction of AVF except in the group of patients with combined thrombophilia. A small number of bleeding complications in our study points to the safety of the applied preventive regimen. Based on the obtained results, prophylactic use of ticlopidine or nadroparin-calcium in preventive doses can be recommended for patients with ESRD immediately after AVF creation. Prophylactic treatment of thrombotic complications in patients with newly created AVF is recommended especially in patients who have had previous thrombosis and/or clinical manifestations of atherosclerotic cardiovascular diseases.</p>

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-04-16T13:26:11Z No. of bitstreams: 2 Dissertação - Jéssica Guimarães Rodrigues - 2018.pdf: 4231969 bytes, checksum: 7cd99fc018c0461eb571ee4a66eb3bbc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-04-16T13:27:10Z (GMT) No. of bitstreams: 2 Dissertação - Jéssica Guimarães Rodrigues - 2018.pdf: 4231969 bytes, checksum: 7cd99fc018c0461eb571ee4a66eb3bbc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-16T13:27:10Z (GMT). No. of bitstreams: 2 Dissertação - Jéssica Guimarães Rodrigues - 2018.pdf: 4231969 bytes, checksum: 7cd99fc018c0461eb571ee4a66eb3bbc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-16 / Hemodialysis is the most common category of kidney replacement therapy set for chronical kidney disease. In order to perform this treatment it’s needed a vascular access (VA) that offers an adequate flow rate, a long use-life and a low rate of complications. The Arteriovenous Fistula (AVF) is the closest access to meet these requirements. It can, however, present complications and, during the cannulation that usually happens three times per week, adverse events (AE) can occur to the patient. The arteriovenous fistula cannulation must happen with safety in order to prevent future patency problems. There are three methods of cannulation: area, rope ladder and buttonhole. In the area method, the insertion points of the needles are in the same area; in the rope ladder method there’s the varying of the place of the puncture, at a distance defined by the previous puncture, all along the VA; and in the buttonhole method, the needle’s insertion happen in the same place, angle and deepness, forming a subcutaneous tunnel that will be cannulated with the blunt needle. Each one of these methods has its own particularity and can influence in the need to repair the fistula. This is a prospective cohort study, during the course of six months, from April to September of 2017, conducted with the participation of 347 patients using the vascular access by autologous arteriovenous fistula, within three hemodialysis clinics in the city of Goiânia - GO. The data collection happened by weekly interview to the patients, using a structured instrument online. The research was approved by the Ethics Committee and the participation conditioned to signing of the consent form by the patient. The general objective was to analyze the factors that can influence in the necessity to repair the arteriovenous fistula of patients in hemodialytic treatment cannulated by different cannulation methods. The specific objective was to relate the adverse events and complications in the different arteriovenous fistula cannulation methods. We’ve found that in the buttonhole method, the most frequent AE was dermatitis and misscannulation, and in the area/rope-ladder methods, the most frequent AE were haematoma and peri-punction bleeding. The patients in the buttonhole method group received the hemodialytic treatment with a higher blood flow compared the other group. We’ve observed that the dual lumen catheter (DLC) is a predictor to the need of AVF repairments, due to enhancing in 28% the risk of need for AFV repair. The “arterial” retrograde cannulation has presented itself as a protection factor, diminishing the need to AVF repairments in 1%. In conclusion, the buttonhole method is recommended, since there is an intermittent surveillance of the arteriovenous fistula by the nurse in the touching exam. The area method is not recommended, and the rope ladder method should be individually evaluated in future studies. The nurse must act by monitoring the AFV, surveillance of the patency parameters and health education to the patients for the AVF self-care, as well as continued education to the nursing team in order to promote safe and scientifically based practices. / A hemodiálise é a modalidade de terapia renal substitutiva mais comumente instituída para a doença renal crônica. Para esse tratamento é necessário um acesso vascular que ofereça fluxo sanguíneo adequado à necessidade dialítica, meia vida longa e baixo índice de complicações. A fístula arteriovenosa é o acesso que mais se aproxima desses requisitos. Porém, não obstante, pode apresentar complicações, e durante as punções, que comumente se repetem três vezes por semana, pode haver eventos adversos (EA) ao paciente. A punção da fístula arteriovenosa deve ser realizada com segurança a fim de prevenir futuros problemas de perviedade. Há três métodos de punção: regional, escada de corda, e buttonhole. No método regional, os pontos de inserção das agulhas são na mesma região; no método escada de corda, há rotação do sítio de punção, a uma distância definida a partir da anterior ao longo de todo o AV; e no buttonhole, a inserção da agulha é no mesmo local, ângulo e profundidade, formando de um túnel subcutâneo que será puncionado com agulha romba. Cada um desses métodos tem sua particularidade e podem influenciar na necessidade para reparos na fístula. Este é um estudo longitudinal de coorte prospectiva, no período de seis meses, abril a setembro de 2017, realizado com 347 pacientes em hemodiálise usando acesso vascular por fístula arteriovenosa autóloga, em três clínicas satélites do município de Goiânia - GO. A coleta de dados foi por entrevista semanal aos pacientes, por meio de instrumento estruturado online. A pesquisa foi aprovada por comitê de ética, e a participação condicionada à assinatura do Termo de Consentimento Livre e Esclarecido do paciente. O objetivo geral foi analisar fatores que influenciam na necessidade de reparo à fístula arteriovenosa de pacientes em hemodiálise puncionados por distintos métodos de punção. E os objetivos específicos foram identificar e relacionar os eventos adversos e complicações em distintos métodos de punção da fístula arteriovenosa, e caracterizar os preditores de complicações da fístula arteriovenosa. Encontramos como resultados que no método de punção de fístula arteriovenosa buttonhole o EA mais frequente foi dermatite e reinserção de agulhas de punção, e nos métodos escada/regional foram hematoma e sangramento peripunção. Os pacientes no grupo puncionado pelo método buttonhole receberam hemodiálise sob fluxos de sangue mais altos comparado ao outro grupo. Observamos que o uso do cateter venoso central de duplo lúmen (CDL) caracteriza-se um preditor de necessidade de reparo da fístula arteriovenosa, pois aumenta em 28% o risco dessa necessidade. A punção “arterial” retrógrada apresentou-se como fator de proteção, diminuindo em 1% a necessidade de reparos. Concluímos que o método de punção buttonhole é recomendado desde que haja a monitoração intermitente da fístula arteriovenosa pelo enfermeiro durante exame físico. O método regional é desestimulado. E o método escada de corda deve ser avaliado individualmente em estudos futuros. O enfermeiro deve estabelecer a vigilância dos parâmetros de perviedade, educação em saúde para autocuidado da fístula arteriovenosa, bem como educação continuada para a equipe de enfermagem a fim de promover práticas seguras e cientificamente embasadas.

Submitted by Fabiana Gonçalves Pinto (benf@ndc.uff.br) on 2015-06-18T15:32:47Z No. of bitstreams: 1 Dejanilton_versão final.pdf: 2073218 bytes, checksum: 30502b09d9c55699b8480f0efd8e0c0c (MD5) / Made available in DSpace on 2015-06-18T15:32:48Z (GMT). No. of bitstreams: 1 Dejanilton_versão final.pdf: 2073218 bytes, checksum: 30502b09d9c55699b8480f0efd8e0c0c (MD5) Previous issue date: 2014 / A doença renal crônica emerge hoje como um sério problema de saúde pública em todo mundo, sendo considerada uma “epidemia” de crescimento alarmante. Um dos grandes desafios do século XXI será minimizar as implicações promovidas por essa patologia no nível econômico e social. O acesso vascular representa uma das principais causas mobilizadoras de recursos financeiros nas pessoas com insuficiência renal crônica terminal (IRCT). A canulação tradicional em fístula arteriovenosa era, até recentemente, a única prática no serviço de hemodiálise (HD). A partir da introdução de uma alternativa de canulação praticada na Europa e Estados Unidos, se evidenciaram melhorias para o paciente com um protocolo rigoroso que ameniza consideravelmente as complicações com os acessos vasculares definitivos para HD. Estudo descritivo, exploratório e retrospectivo de abordagem quantiqualitativa sobre a técnica de botoeira à pacientes com IRCT, com fístula arteriovenosa pelo Sistema Único de Saúde (SUS), tendo como objetivos: descrever a técnica de botoeira no serviço de hemodiálise; identificar os desfechos da utilização da técnica de botoeira dos pacientes em programa regular de HD durante os últimos três anos; comparar os desfechos obtidos da aplicação da técnica de botoeira em relação à ropeladder e; discutir a técnica de botoeira como indicador de qualidade do cuidado de enfermagem oferecido ao paciente em tratamento hemodialítico usuário do SUS no ambiente de um serviço privado. O cenário foi uma clínica privada conveniada ao SUS localizada na região metropolitana do estado do Rio de Janeiro. A amostra foi constituída por 94 pacientes, e a coleta de dados foi realizada por meio dos prontuários, questionário semiestruturado e entrevista semiestruturada. Do estudo emergiram dados que descrevem a implantação da técnica de botoeira, dados comparativos entre a técnica de botoeira e ropeladder e entrevista sobre a satisfação do uso da técnica de botoeira. Os dados foram analisados utilizando o programa SPSS 17.0, software Bioestat e análise de conteúdo de Bardin. Conclui-se que a técnica de botoeira demonstrou-se benéfica ao paciente em terapia hemodialítica em todos os aspectos, com ênfase nos aspectos de dor, autoimagem e autoestima. Permitiu observar, também, que os gastos dos cofres públicos com acesso vascular definitivo foram diminuídos e será necessária a divulgação deste estudo no âmbito nacional e internacional para disseminação da informação. Ressalta-se a importância de novos estudos para criação e validação de um protocolo que seja viável na utilização da técnica de botoeira aos pacientes submetidos à terapia hemodialítica no Brasil. / Chronic kidney disease emerges today as a serious public health problem worldwide and is considered an "epidemic" of alarming growth. One of the great challenges of the 21st century will minimize the implications promoted by this pathology in the economic and social level. The vascular access is one of the main causes of mobilizing financial resources in people with chronic kidney disease (CKD). The traditional cannulation in arteriovenous fistula was, until recently, the only practical in hemodialysis (HD) services. From the introduction of an alternative cannulation practiced in Europe and the United States, noted improvements for the patient with a strict protocol that greatly eases the complications with the definitive vascular access for HD. Descriptive, exploratory and retrospective study of quantiqualitative approach about the buttonhole technique to CKD patients with arteriovenous fistula by the Unified Health System (UHS), having as objectives: to describe the buttonhole technique in HD services; identify the outcomes of using the buttonhole technique of the patients in a HD regular program during the last three years; compare outcomes obtained from the application of the buttonhole technique in relation to ropeladder and; discuss the buttonhole technique as a quality indicator of the nursing care provided to patients in UHS HD user treatment in a private service. The study setting was a private clinic contracted to UHS located in the metropolitan region of the state of Rio de Janeiro. The sample consisted of 94 patients, and data collection was performed by means of the medical records, semi-structured questionnaire and semi-structured interview. Emerged data describing the implementation of the buttonhole technique, comparative data between the buttonhole technique and ropeladder and interview on satisfaction of using the buttonhole technique. Data were analyzed using SPSS 17.0 software and Bioestat and content analysis by Bardin. It concludes that the buttonhole technique proved to be beneficial to the patient in hemodialysis in all aspects, with emphasis on aspects of pain, self-image and self-esteem. Was observed that the expenditure of public funds with definitive vascular access were decreased and will require the disclosure of this study in the national and international level for dissemination of information. We emphasize the importance of new studies for the development and validation of a protocol that is viable in the use of the buttonhole technique for patients undergoing HD in Brazil.

Une fistule artérioveineuse (FAV) est un accès vasculaire permanent créé par voie chirurgicale en connectant une veine et une artère chez le patient en hémodialyse. Cet accès vasculaire permet de mettre en place une circulation extracorporelle partielle afin de remplacer les fonctions exocrines des reins. En France, environ 36000 patients sont atteint d’insuffisance rénale chronique en phase terminale, stade de la maladie le plus grave qui nécessite la mise en place d’un traitement de suppléance des reins : l’hémodialyse. La création et présence de la FAV modifient significativement l’hémodynamique dans les vaisseaux sanguins, au niveau local et systémique ainsi qu’à court et à plus long terme. Ces modifications de l’hémodynamiques peuvent induire différents pathologies vasculaires, comme la formation d’anévrysmes et de sténoses. L’objectif de cette étude est de mieux comprendre le comportement mécanique et l’hémodynamique dans les vaisseaux de la FAV. Nous avons étudié numériquement les interactions fluide-structure (IFS) au sein d’une FAV patient-spécifique, dont la géométrie a été reconstruite à partir d’images médicales acquises lors d’un précédent doctorat. Cette FAV a été créée chez le patient en connectant la veine céphalique du patient à l’artère radiale et présente une sténose artérielle réduisant de 80% la lumière du vaisseau. Nous avons imposé le profil de vitesse mesuré sur le patient comme conditions aux limites en entrée et un modèle de Windkessel au niveau des sorties artérielle et veineuse. Nous avons considéré des propriétés mécaniques différentes pour l’artère et la veine et pris en compte le comportement non-Newtonien du sang. Les simulations IFS permettent de calculer l’évolution temporelle des contraintes hémodynamiques et des contraintes internes à la paroi des vaisseaux. Nous nous sommes demandées aussi si des simulations non couplées des équations fluides et solides permettaient d’obtenir des résultats suffisamment précis tout en réduisant significativement le temps de calcul, afin d’envisager son utilisation par les chirurgiens. Dans la deuxième partie de l’étude, nous nous sommes intéressés à l’effet de la présence d’une sténose artérielle sur l’hémodynamique et en particulier à ses traitements endovasculaires. Nous avons dans un premier temps simulé numériquement le traitement de la sténose par angioplastie. En clinique, les sténoses résiduelles après angioplastie sont considérées comme acceptables si elles obstruent moins de 30% de la lumière du vaisseau. Nous avons donc gonflé le ballonnet pour angioplastie avec différentes pressions de manière à obtenir des degrés de sténoses résiduelles compris entre 0 et 30%. Une autre possibilité pour traiter la sténose est de placer un stent après l’angioplastie. Nous avons donc dans un deuxième temps simulé ce traitement numériquement et résolu le problème d’IFS dans la fistule après la pose du stent. Dans ces simulations, la présence du stent a été prise en compte en imposant les propriétés mécaniques équivalentes du vaisseau après la pose du stent à une portion de l’artère. Dans la dernière partie de l’étude nous avons mis en place un dispositif de mesure par PIV (Particle Image Velocimetry). Un moule rigide et transparent de la géométrie a été obtenu par prototypage rapide. Les résultats expérimentaux ont été validés par comparaison avec les résultats des simulations numériques. / An arteriovenous fistula (AVF) is a permanent vascular access created surgically connecting a vein onto an artery. It enables to circulate blood extra-corporeally in order to clean it from metabolic waste products and excess of water for patients with end-stage renal disease undergoing hemodialysis. The hemodynamics results to be significantly altered within the arteriovenous fistula compared to the physiological situation. Several studies have been carried out in order to better understand the consequences of AVF creation, maturation and frequent use, but many clinical questions still lie unanswered. The aim of the present study is to better understand the hemodynamics within the AVF, when the compliance of the vascularwall is taken into account. We also propose to quantify the effect of a stenosis at the afferent artery, the incidence of which has been underestimated for many years. The fluid-structure interactions (FSI) within a patient-specific radio-cephalic arteriovenous fistula are investigated numerically. The considered AVF presents an 80% stenosis at the afferent artery. The patient-specific velocity profile is imposed at the boundary inlet, and a Windkessel model is set at the arterial and venous outlets. The mechanical properties of the vein and the artery are differentiated. The non-Newtonian blood behavior has been taken into account. The FSI simulation advantageously provides the time-evolution of both the hemodynamic and structural stresses, and guarantees the equilibrium of the solution at the interface between the fluid and solid domains. The FSI results show the presence of large zones of blood flow recirculation within the cephalic vein, which might promote neointima formation. Large internal stresses are also observed at the venous wall, which may lead to wall remodeling. The fully-coupled FSI simulation results to be costly in computational time, which can so far limit its clinical use. We have investigated whether uncoupled fluid and structure simulations can provide accurate results and significantly reduce the computational time. The uncoupled simulations have the advantage to run 5 times faster than the fully-coupled FSI. We show that an uncoupled fluid simulation provides informative qualitative maps of the hemodynamic conditions in the AVF. Quantitatively, the maximum error on the hemodynamic parameters is 20%. The uncoupled structural simulation with non-uniform wall properties along the vasculature provides the accurate distribution of internal wall stresses, but only at one instant of time within the cardiac cycle. Although partially inaccurate or incomplete, the results of the uncoupled simulations could still be informative enough to guide clinicians in their decision-making. In the second part of the study we have investigated the effects of the arterial stenosis on the hemodynamics, and simulated its treatment by balloon-angioplasty. Clinically, balloon-angioplasty rarely corrects the stenosis fully and a degree of stenosis remains after treatment. Residual degrees of stenosis below 30% are considered as successful. We have inflated the balloon with different pressures to simulate residual stenoses ranging from 0 to 30%. The arterial stenosis has little impact on the blood flow distribution: the venous flow rate remains unchanged before and after the treatment and thus permits hemodialysis. But an increase in the pressure difference across the stenosis is observed, which could cause the heart work load to increase. To guarantee a pressure drop below 5 mmHg, which is considered as the threshold stenosis pressure difference clinically, we find that the residual stenosis degree must be 20% maximum.