674 resultados para ELUTING STENTS
Resumo:
FUNDAMENTO: Remodelamento ventricular esquerdo (RVE) após IAM caracteriza fator de mau prognóstico. Há pouca informação na literatura sobre o RVE analisado com ecocardiografia tridimensional (ECO 3D) OBJETIVO: Analisar com ECO 3D as modificações geométricas e volumétricas do ventrículo esquerdo (VE) seis meses após IAM em pacientes submetidos a tratamento primário percutâneo. MÉTODOS: Estudo prospectivo com ECO 3D de 21 indivíduos (16 homens, 56 ± 12 anos), acometidos por IAM com elevação do segmento ST. Foi feita a análise morfofuncional (VE) com ECO 3D (volumes, FEVE, índice de esfericidade 3D) até sete dias e seis meses após o IAM. RVE foi considerado para aumento > 15% do volume diastólico final do VE (VDFVE) após seis meses do IAM, comparado ao VDFVE até sete dias do evento. RESULTADOS: Oito (38%) pacientes apresentaram RVE. Medidas ecocardiográficas (n = 21 pacientes): I- até sete dias do IAM: 1- VDFVE: 92,3 ± 22,3 mL; 2- FEVE: 0,51 ± 0,01; 3- índice de esfericidade: 0,38 ± 0,05; II- após seis meses: 1- VDFVE: 107,3 ± 26,8 mL; 2- FEVE: 0,59 ± 0,01; 3- índice de esfericidade: 0,31 ± 0,05. Coeficiente de correlação (r) entre índice de esfericidade até sete dias do IAM e VDFVE aos seis meses (n = 8) após o IAM: r: 0,74, p = 0,0007; (r) entre índice de esfericidade após seis meses do IAM e VDFVE aos seis meses do IAM: r: 0,85, p < 0,0001. CONCLUSÃO: Nesta série, foi observado RVE em 38% dos pacientes seis meses após IAM. O índice de esfericidade tridimensional foi associado à ocorrência de RVE.
Resumo:
FUNDAMENTO: O impacto do uso do ultrassom intracoronariano (USIC) na implantação de stents tem resultados inconclusivos. OBJETIVO: Revisão sistemática, com metanálise, do impacto do USIC na implantação de stents quanto à evolução clínica e angiográfica. MÉTODOS: Efetuada busca nas bases Medline/Pubmed, CENTRAL, Embase, Lilacs, Scopus e Web of Science. Incluídos estudos clínicos randomizados (ECR) que avaliaram o implante de stents, orientados pela USIC, comparados com aqueles utilizando a angiografia isoladamente (ANGIO). O intervalo mínimo de acompanhamento foi de seis meses, avaliados os desfechos: trombose, mortalidade, infarto do miocárdio, revascularização percutânea e cirúrgica, eventos cardiovasculares maiores (ECVM) e reestenose. Os desfechos binários foram apresentados considerando o número de eventos em cada grupo; as estimativas foram geradas por um modelo de efeitos aleatórios, considerando a estatística de Mantel-Haenzel como ponderadora e magnitude de efeito ao risco relativo (RR) com seu respectivo intervalo de confiança de 95% (IC 95%). Para quantificação da consistência entre os resultados de cada estudo, utilizou-se o teste de inconsistência I² de Higgins. RESULTADOS: Avaliados 2.689 artigos, incluídos 8 ECR. Houve redução de 27% na reestenose angiográfica (RR: 0,73; IC 95%: 0,54 - 0,97; I² = 51%) e redução estatisticamente significativa nas taxas de revascularizações percutânea e geral (RR: 0,88; IC 95%: 0,51 - 1,53; I² = 61% e RR: 0,73; IC 95%: 0,54 - 0,99; I² = 55%), sem diferença estatística na revascularização cirúrgica (RR: 0,95; IC 95%: 0,52 - 1,74; I² = 0%) em favor do USIC vs. ANGIO. Não foram observadas diferenças nos demais desfechos na comparação entre as duas estratégias. CONCLUSÃO: Angioplastias com implante de stents guiadas por USIC reduzem taxas de reestenose e de revascularizações, não tendo impacto nos desfechos ECVM, infarto agudo do miocárdio, mortalidade ou trombose.
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FUNDAMENTO: Na angioplastia coronária percutânea (ACP), os vasos de fino calibre representam um fator de risco para reestenose. O stent farmacológico (SF) autoexpansível Sparrow®, de perfil menor que os sistemas atuais, nunca foi testado nesse cenário. OBJETIVOS: Avaliar a eficácia tardia do SF Sparrow®, com relação à perda luminal tardia intrastent (PLT intrastent) aos oito meses. MÉTODOS: Estudo prospectivo, randomizado, em P com doença arterial coronária (DAC) sintomática ou com isquemia documentada, submetido à ACP em vasos de calibre < 2,75 mm, dividido em dois grupos quanto ao tipo de stent Sparrow®: grupo 1, SF; grupo 2, stent não farmacológico (SNF). O seguimento clínico foi de 12 meses. De imediato e aos oito meses, avaliação pela angiografia coronária quantitativa (ACQ). Para o cálculo da amostra estimou-se diminuição de mais de 65% de PLT intrastent com o SF. Para análise estatística utilizou-se o programa IBM SPSS Statistics® versão 19 (Chicago, Illinois, EUA). RESULTADOS: Foram incluídos 24 p, 12 em cada grupo. Os grupos SF e SNF foram semelhantes quanto à idade (63,25 ± 10,01 versus 64,58 ± 11,54, p = 0,765), sexo masculino (58,3% versus 33,3%, p = 0,412), fatores de risco e todos os aspectos angiográficos. Os resultados imediatos foram satisfatórios em ambos os grupos. Aos oito meses, a PLT intrastent foi significativamente menor no SF do que no SNF (SF 0,25 ± 0,16 versus SNF 0,97 ± 0,76, p = 0,008). CONCLUSÃO: Em ACP de vasos de calibre < 2,75 mm, o SF Sparrow® determinou significativa redução da PLT intrastent, em comparação ao SNF Sparrow®.
Resumo:
Fundamento: Stents recobertos com polímeros bioabsorvíveis e fármacos apenas na face abluminal podem ser mais seguros que stents farmacológicos com polímeros permanentes. Objetivo: Relatar os resultados experimentais com o stent Inspiron(r), um stent recoberto com polímero bioabsorvível e com liberação de sirolimus apenas da face abluminal, recentemente aprovado para uso clínico. Métodos: Foram implantados 45 stents nas artérias coronárias de 15 porcos e, no 28° dia pós-implante, foram obtidos os resultados angiográficos, de ultrassonografia intracoronária e de histomorfologia. Cinco grupos foram avaliados: Grupo I (nove stents sem recobrimento); Grupo II (nove stents com polímero bioabsorvível nas faces luminal e abluminal); Grupo III (oito stents com polímero bioabsorvível na face abluminal); Grupo IV (nove stents com polímero bioabsorvível e sirolimus nas faces luminal e abluminal); e Grupo V (dez stents com polímero bioabsorvível e sirolimus na face abluminal exclusivamente). Resultados: Observamos, para os Grupos I, II, III, IV e V respectivamente: porcentual de estenose de 29 ± 20; 36 ± 14; 33 ± 19; 22 ± 13 e 26 ± 15 (p = 0,443); perda luminal tardia (em mm) de 1,02 ± 0,60; 1,24 ± 0,48; 1,11 ± 0,54; 0,72 ± 0,44 e 0,78 ± 0,39 (p = 0,253); área neointimal (em mm2) de 2,60 ± 1,99; 2,74 ± 1,51; 2,74 ± 1,30; 1,30 ± 1,14 e 0,97 ± 0,84 (p = 0,001; Grupos IV e V versus Grupos I, II e III) e porcentual de área neointimal de 35 ± 25; 38 ± 18; 39 ± 19; 19 ± 18 e 15 ± 12 (p = 0,001; Grupo IV e V versus Grupo I, II e III). Os escores de injúria e inflamação foram baixos e sem diferenças entre os grupos. Conclusão: O stent Inspiron(r) foi seguro e inibiu significativamente a hiperplasia neointimal observada no 28° dia pós-implante em artérias coronárias porcinas.
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Introduction: Renal transplantation is considered the treatment of choice for end-stage renal disease. However, the association of occlusive aorto-iliac disease and chronic renal failure is frequent and aorto-iliac reconstruction may be necessary prior to renal transplantation. This retrospective study reviews the results of this operative strategy.Material and Methods: Between January 2001 and June 2010, 309 patients underwent renal transplantation at our institution and 8 patients had prior aorto-iliac reconstruction using prosthetic material. There were 6 men and 2 women with a median age of 62 years (range 51-70). Five aorto-bifemoral and 2 aorto-bi-iliac bypasses were performed for stage II (n=5), stage IV (n=1) and aortic aneurysm (n=1). In one patient, iliac kissing stents and an ilio-femoral bypass were implanted. 4 cadaveric and 4 living donor renal transplantations were performed with an interval of 2 months to 10 years after revascularization.The results were analysed with respect of graft and patients survival. Differences between groups were tested by the log rank method.Results: No complications and no death occurred in the post-operative period. All bypasses remained patent during follow-up. The median time of post transplantation follow-up was 46 months for all patients and 27 months for patients with prior revascularization. In the revascularized group and control group, the graft and patient survival at 1 year were respectively 100%/96%, 100%/99% and at 5 years 86%/86%, 86%/94%, without significant differences between both groups.Discussion: Our results suggest that renal transplantation following prior aorto-iliac revascularisation with prosthetic material is safe and effective. Patients with end-stage renal disease and concomitant aorto-iliac disease should therefore be considered for renal transplantation. However, caution in the interpretation of the results is indicated due to the small sample size of our study.
Resumo:
PURPOSE: To evaluate the feasibility of visualizing the stent lumen using coronary magnetic resonance angiography in vitro. MATERIAL AND METHODS: Nineteen different coronary stents were implanted in plastic tubes with an inner diameter of 3 mm. The tubes were positioned in a plastic container filled with gel and included in a closed flow circuit (constant flow 18 cm/sec). The magnetic resonance images were obtained with a dual inversion fast spin-echo sequence. For intraluminal stent imaging, subtraction images were calculated from scans with and without flow. Subsequently, intraluminal signal properties were objectively assessed and compared. RESULTS: As a function of the stent type, various degrees of in-stent signal attenuation were observed. Tantalum stents demonstrated minimal intraluminal signal attenuation. For nitinol stents, the stent lumen could be identified, but the intraluminal signal was markedly reduced. Steel stents resulted in the most pronounced intraluminal signal voids. CONCLUSIONS: With the present technique, radiofrequency penetration into the stents is strongly influenced by the stent material. Thesefindings may have important implicationsforfuture stent design and stent imaging strategies.
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OBJECTIVE: To evaluate morphological and perfusion changes in liver metastases of neuroendocrine tumours by contrast-enhanced ultrasound (CEUS) after transarterial embolisation with bead block (TAE) or trans-arterial chemoembolisation with doxorubicin-eluting beads (DEB-TACE). METHODS: In this retrospective study, seven patients underwent TAE, and ten underwent DEB-TACE using beads of the same size. At 1 day before embolisation, 2 days, 1 month and 3 months after the procedure, a destruction-replenishment study using CEUS was performed with a microbubble-enhancing contrast material on a reference tumour. Relative blood flow (rBF) and relative blood volume (rBV) were obtained from the ratio of values obtained in the tumour and in adjacent liver parenchyma. Morphological parameters such as the tumour's major diameter and the viable tumour's major diameter were also measured. A parameter combining functional and morphological data, the tumour vitality index (TVI), was studied. The Wilcoxon rank-sum test and Fisher's test were used to compare treatment groups. RESULTS: At 3 months rBF, rBV and TVI were significantly lower (P = 0.005, P = 0.04 and P = 0.03) for the group with doxorubicin. No difference in morphological parameters was found throughout the follow-up. CONCLUSIONS: One parameter, TVI, could evaluate the morphological and functional response to treatments.
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Matrix effects, which represent an important issue in liquid chromatography coupled to mass spectrometry or tandem mass spectrometry detection, should be closely assessed during method development. In the case of quantitative analysis, the use of stable isotope-labelled internal standard with physico-chemical properties and ionization behaviour similar to the analyte is recommended. In this paper, an example of the choice of a co-eluting deuterated internal standard to compensate for short-term and long-term matrix effect in the case of chiral (R,S)-methadone plasma quantification is reported. The method was fully validated over a concentration range of 5-800 ng/mL for each methadone enantiomer with satisfactory relative bias (-1.0 to 1.0%), repeatability (0.9-4.9%) and intermediate precision (1.4-12.0%). From the results obtained during validation, a control chart process during 52 series of routine analysis was established using both intermediate precision standard deviation and FDA acceptance criteria. The results of routine quality control samples were generally included in the +/-15% variability around the target value and mainly in the two standard deviation interval illustrating the long-term stability of the method. The intermediate precision variability estimated in method validation was found to be coherent with the routine use of the method. During this period, 257 trough concentration and 54 peak concentration plasma samples of patients undergoing (R,S)-methadone treatment were successfully analysed for routine therapeutic drug monitoring.
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A cardiac-triggered free-breathing three-dimensional (3D) balanced fast field-echo projection renal magnetic resonance (MR) angiographic sequence was investigated for in-stent lumen visualization of a dedicated metallic renal artery stent. Fourteen prototype stents were deployed in the renal arteries of six pigs (in two pigs, three stents were deployed). Projection renal MR angiography was compared with standard contrast material-enhanced 3D breath-hold MR angiography. Artifact-free in-stent lumen visualization was achieved with both projection MR angiography and contrast-enhanced MR angiography. These promising results warrant further studies for visualization of in-stent restenosis.
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A mycotic pseudoaneurysm of the popliteal artery is usually a consequence of septic embolization and often a result of bacterial endocarditis. Conventional treatment is surgical and avoids the placement of foreign material in infected sites. Here we report our treatment of a 59-year-old man who presented with a rupture of a mycotic pseudoaneurysm of the popliteal artery due to septic embolism from sternoclavicular infectious arthritis. Radiological investigations are included. This is the first documented case of septic arthritis complicated by a rupture of a mycotic popliteal false aneurysm and treated using an endovascular procedure. Combining endovascular stent grafts with evacuation of the joint abscess and antibiotic therapy can offer a safe alternative for frail and unstable patients.
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Coronary magnetic resonance angiography (MRA) is a technique aimed at establishing a noninvasive test for the assessment of significant coronary stenoses. There are certain boundary conditions that have hampered the clinical success of coronary MRA and coronary vessel wall imaging. Recent advances in hardware and software allow for consistent visualization of the proximal and mid portions of the native coronary arteries. Current research focuses on the use of intravascular MR contrast agents and black blood coronary angiography. One common goal is to create a noninvasive test which might allow for screening for major proximal and mid coronary artery disease. These novel approaches will represent a major step forward in diagnostic cardiology.