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1.
Angiología ; 54(4): 317-326, jul. 2002. ilus
Artigo em Es | IBECS | ID: ibc-16329

RESUMO

Objetivo. Identificar posibles factores relacionados con la oclusión de los injertos suprageniculares de politetrafluoroetileno (PTFE). Pacientes y métodos. Estudio de 100 injertos femoropoplíteos suprageniculares de PTFE realizados en 98 pacientes (77 varones y 21 mujeres, con una edad media de 69 años; intervalo: 49-90 años). En 90 casos se indicó la revascularización por isquemia crítica de laextremidad y en 10 por claudicación intermitente. Estudio observacional retrospectivo durante un período de cinco años. Se evaluaron los parámetros siguientes: edad (mayor o menor de 65 años), sexo, factores de riesgo cardiovasculares, índice tobillo/brazo, salida distal, fibrinógeno (superior o inferior a la media de 5,7 g/ L) y celularidad sanguínea: hematocrito >45 per cent, leucocitos >10.000 y plaquetas >250.000. Para el análisis estadístico se utilizó la regresión multivariante de Cox y tablas devida Kaplan-Meier. Resultados. La permeabilidad a los 30 días fue del 99 per cent, y la acumulativa a 1, 2 y 5 años fue del 75, 56 y 41 per cent, respectivamente. El 75 per cent de las oclusiones se produjeron en los primeros 18 meses (permeabilidad del 67 per cent). En este período de 18 meses el único factor predictivo de oclusión de los injertos fue el fibrinógeno y la celularidad sanguínea (p< 0,05). A los cinco años los factores predictivos de oclusión fueron la salida distal (p= 0,01), fibrinógeno (p= 0,001) y celularidad sanguínea (p= 0,001). La permeabilidad secundaria fue del 41 per cent y el salvamento de extremidad del 82 per cent a los cinco años. Conclusión. Cifras altas de fibrinógeno y celularidad sanguínea influyen negativamente en la permeabilidad de los injertos suprageniculares de PTFE (AU)


Assuntos
Idoso , Feminino , Masculino , Humanos , Politetrafluoretileno/administração & dosagem , Politetrafluoretileno/uso terapêutico , Permeabilidade Capilar , Fibrinogênio/administração & dosagem , Claudicação Intermitente/diagnóstico , Claudicação Intermitente , Angiografia/métodos , Inibidores da Agregação Plaquetária/administração & dosagem , Oclusão de Enxerto Vascular/diagnóstico , Permeabilidade Capilar , Prótese Vascular/métodos , Prótese Vascular/instrumentação , Próteses e Implantes/efeitos adversos , Próteses e Implantes , Fatores de Risco , Estudos Retrospectivos , Próteses e Implantes
2.
Rev. sanid. mil ; 52(5): 238-41, sept.-oct. 1998. tab
Artigo em Espanhol | LILACS | ID: lil-240850

RESUMO

De agosto de 1996 a mayo de 1997, fueron estudiados 16 pacientes entre las edades de 4 meses a 31 años siendo el promedio de edad 4.4 años, a los cuales se les realizó cierre del conducto arterioso mediante técnica transcatéter con dispositivo endovascular (coil). El diagnóstico de conducto arterioso permeable se realizó mediante clínica, por la presencia de soplo continuo en la porción superior del borde esternal izquierdo, mediante tele Rx de tórax, por la evidencia de cardiomegalia e hiperflujo pulmonar y electrocardiográficamente por datos de crecimiento auricular izquierdo y sobrecarga de ventrículos. Ecorcardiográficamente mediante flujo Doppler color. El criterio de inclusión clínica para este estudio fue la presencia del conducto arterioso permeable con un diámetro menor de 3.5 mm, sin lesiones asociadas. De los 16 pacientes se logró la oclusión exitosa del conducto arterioso permeable en 12 casos, lo que nos da un porcentaje de éxito de un 75 por ciento, sin complicaciones mayores y un promedio de estancia hospitalaria de 1.1 días. La falla en la técnica se presentó en cuatro pacientes, los cuales tenían un conducto arterioso permeable con un diámetro mayor a 4 milímetros


Assuntos
Humanos , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Prótese Vascular/instrumentação , Prótese Vascular , Prótese Vascular , Ecocardiografia Doppler , Permeabilidade do Canal Arterial/cirurgia , Permeabilidade do Canal Arterial/complicações , Permeabilidade do Canal Arterial/diagnóstico , Hospitais Militares , Cateterismo Cardíaco/métodos , Cateterismo Cardíaco
3.
J Vasc Surg ; 26(2): 210-21, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9279307

RESUMO

PURPOSE: This report describes our experience with endovascular repair of aortic and iliac anastomotic aneurysms. METHODS: Between June 1994 and March 1996, 12 noninfected aortic or iliac anastomotic aneurysms in 10 patients who had serious comorbid medical conditions that precluded or made difficult standard operative repair were treated using endovascular grafts. No patient in this study had a history of fever, leukocytosis, or computed tomographic evidence of a periprosthetic fluid collection that was suggestive of infection of the original graft. Endovascular grafts composed of polytetrafluoroethylene and balloon-expandable stents were introduced through a femoral arteriotomy and were placed using over-the-wire techniques under C-arm fluoroscopic guidance. RESULTS: Endovascular grafts were successfully inserted in all patients with aortic or iliac anastomotic aneurysms. There were no procedure-related deaths, and complications included one postprocedure wound hematoma and one perioperative myocardial infarction. Graft patency has been maintained for a mean of 16.1 months, with no computed tomographic evidence of aneurysmal enlargement or perigraft leakage. CONCLUSIONS: Endovascular grafts appear to be a safe and effective technique for excluding some noninfected aortoiliac anastomotic aneurysms in high-risk patients and may become a treatment option in all patients who have clinically significant lesions.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Prótese Vascular/instrumentação , Aneurisma Ilíaco/cirurgia , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/efeitos adversos , Angiografia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/etiologia , Prótese Vascular/efeitos adversos , Prótese Vascular/métodos , Feminino , Humanos , Aneurisma Ilíaco/diagnóstico por imagem , Aneurisma Ilíaco/etiologia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Grau de Desobstrução Vascular
4.
J Endovasc Surg ; 4(3): 272-8, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9291052

RESUMO

PURPOSE: To evaluate different ultrasound modalities during implantation and follow-up of endovascular grafts for abdominal aortic aneurysm (AAA) exclusion. METHODS: Between February 1995 and May 1996, 18 patients (14 men; aged 49 to 80 years, mean 67) were treated with endovascular intervention for infrarenal AAA. Seventeen patients received Mialhe Stentor bifurcated grafts, while one patient was treated with a straight graft for pseudoaneurysm. During and after the implantation, 3.25- and 5-MHz annular array ultrasound probes were used for transabdominal visualization of the endograft. Intravascular ultrasound was applied in combination with angiography for postoperative control. RESULTS: Intraprocedurally, transabdominal two-dimensional (2D) ultrasound successfully monitored guidewire passage from the groin into the main part of the bifurcated endograft for implantation of the second limb. All implantation procedures were technically successful, but four endoleaks were identified intraprocedurally by 2D ultrasound and angiography. One healed spontaneously, two were treated with endovascular techniques at 1 and 4 months, and the last leak was scheduled for repair when the patient died of probable myocardial infarction at 2 months. During follow-up, 2D ultrasound successfully visualized all the endografts; no endoleaks were found in up to 18 months of surveillance. CONCLUSIONS: Transabdominal ultrasound imaging could be valuable in bifurcated endograft deployment both for guiding guidewire insertion and for controlling wire position before the second graft limb is connected to the main graft. Provided that satisfactory visualization of the entire endograft can be obtained, ultrasound examination may possibly replace arteriography and computed tomographic scanning as a follow-up investigation.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Prótese Vascular/instrumentação , Ultrassonografia de Intervenção , Idoso , Idoso de 80 Anos ou mais , Aortografia , Feminino , Seguimentos , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
5.
Br J Surg ; 84(6): 797-9, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9189090

RESUMO

BACKGROUND: Endovascular repair of infrarenal aortic aneurysms is a feasible technique, but up to 30 per cent of patients may be excluded on the basis of a short proximal aortic neck. METHODS: A dissection study was performed on 65 cadavers to measure the distance between the superior mesenteric and renal artery ostia, and to document the points of origin of the renal arteries. RESULTS: The interostial distance did not differ significantly between aneurysmal and non-aneurysmal aortas (P = 0.90 for the left renal artery; P = 0.72 for the right). The median distance was 0.7 cm. The renal arteries originated between 2 and 4 o'clock on the left and between 9 and 10 o'clock on the right. CONCLUSION: The relative consistency of the anatomy in this region may allow the development of a new stent which would increase the number of patients suitable for endovascular repair.


Assuntos
Aneurisma da Aorta Abdominal/patologia , Prótese Vascular/instrumentação , Artéria Renal/patologia , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/cirurgia , Cadáver , Dissecação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Stents
6.
J Endovasc Surg ; 4(2): 124-36, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9185000

RESUMO

PURPOSE: To report a > 3-year experience with a modular, balloon-expandable endovascular graft used for aneurysm exclusion in the aorta and other arteries. METHODS: The customized White-Yu Endovascular GAD Graft, a woven polyester prosthesis with an intrinsic Elgiloy wire graft attachment system along the body of the graft, is a flexible endograft design available in straight, tapered, and bifurcated versions that can be delivered transluminally through 18F to 24F sheaths. RESULTS: Since July 1993, 93 patients have received the White-Yu endograft for treatment of 76 abdominal aortic, 3 thoracic aortic, 13 iliac, and 1 popliteal aneurysms. Of the 79 aortic procedures, 39 involved straight tube grafts, 20 were tapered aortoiliac models, and 20 were bifurcated devices. Success rates for tube grafts were 81% in the abdominal aorta and 100% for the thoracic aorta; 5 primary endoleaks (14%) and 2 conversions to surgery (5.6%) occurred with this graft type. Aortoiliac grafts were deployed successfully in 95% (19/20) of cases with 1 conversion (5%) due to thrombosis. Seventy-five percent of the bifurcated endograft procedures were successful, with 4 conversions (20%) for technical failures and 1 graft thrombosis. Four additional endografts were deployed to treat two primary and two secondary endoleaks in tube graft patients. Two access-related arterial injuries were treated surgically. There was one case of embolus to the distal femoral artery but no microembolization. Overall perioperative (30-day) mortality was 3.1%. Over a mean 18-month follow-up (range 2 to 39), no late graft thrombosis, stenosis, or graft migration has been seen on CT scans or X ray. Endoleak has not been detected in any aortoiliac or bifurcated graft. Aneurysm size has diminished consistently in successfully treated cases. CONCLUSIONS: The White-Yu endograft appears to offer a safe, efficacious, and minimally invasive means of excluding aneurysms from the circulation. Improvements in patient selection, surgical techniques, and equipment have reduced the incidence of endoleak and conversion to open repair over the course of the evaluation.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Prótese Vascular/instrumentação , Aneurisma Ilíaco/cirurgia , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Angiografia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Seguimentos , Migração de Corpo Estranho/diagnóstico por imagem , Migração de Corpo Estranho/etiologia , Migração de Corpo Estranho/mortalidade , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/mortalidade , Humanos , Aneurisma Ilíaco/diagnóstico por imagem , Complicações Intraoperatórias/mortalidade , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/cirurgia , Desenho de Prótese , Falha de Prótese , Estudos Retrospectivos , Segurança , Taxa de Sobrevida , Trombose/diagnóstico por imagem , Trombose/etiologia , Trombose/mortalidade , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
J Endovasc Surg ; 4(2): 147-51, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9185002

RESUMO

PURPOSE: To summarize the results of endovascular abdominal aortic aneurysm (AAA) treatment using several endograft designs over a 4.5-year experience and offer comparisons on the various devices. METHODS: From May 1992 to August 1996, 121 AAA patients meeting the criteria for an endoluminal repair were treated with 1 of 5 endograft designs in three configurations. The endografts were implanted in the operating room under fluoroscopic control. Follow-up included contrast-enhanced computed tomography within 10 days of operation, 6 months postoperatively, and annually thereafter. RESULTS: Endografts were successfully deployed in 106 patients (88%). Fifteen cases were converted to open repair. Six procedure-related deaths occurred within 30 days owing to myocardial infarction (3), combined renal failure and septicemia (2), and multisystem failure (1). There were 36 local/vascular complications (30%) and 18 systemic/remote complications (15%). Of the 121 patients undergoing endoluminal AAA repair, 93 (77%) are currently alive and well with their AAAs excluded from the circulation. CONCLUSIONS: Trends in endoluminal AAA repair and prosthetic design point toward simpler devices and earlier treatment of smaller aneurysms once the long-term outcome of aortic endografting has been determined.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Prótese Vascular/instrumentação , Aneurisma da Aorta Abdominal/classificação , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Prótese Vascular/normas , Seguimentos , Humanos , Complicações Pós-Operatórias/classificação , Complicações Pós-Operatórias/mortalidade , Desenho de Prótese/tendências , Intensificação de Imagem Radiográfica , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
J Endovasc Surg ; 4(2): 195-202, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9185007

RESUMO

PURPOSE: To review the anatomic factors crucial to successful endoluminal abdominal aortic aneurysm (AAA) repair and propose an ideal endograft design for AAA exclusion. METHODS AND RESULTS: The anatomic features of critical importance to endovascular AAA exclusion comprise remote arterial access, proximal and distal fixation sites, AAA morphology, and arterial wall pathology. When designing an aortic endograft, the major components to consider are stent selection, graft material, and the delivery system. The ideal endograft design must be sufficiently versatile to treat a broad range of patients. To meet this requirement, the endograft should display a high degree of dimensional adaptability. A modular bifurcated endograft design permits intraoperative customization to tailor the device to each patient's anatomy and pathology. CONCLUSIONS: The modular stent-graft concept addresses many of the important factors in the evolution toward an ideal aortic endograft. Extensive testing will be needed to determine if the bifurcated stent-graft described here is the optimal design for effective AAA exclusion.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Prótese Vascular/normas , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/patologia , Aortografia , Prótese Vascular/instrumentação , Humanos , Desenho de Prótese , Stents/normas
9.
Cathet Cardiovasc Diagn ; 40(3): 315-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9062733

RESUMO

The coronary physiology of a prosthetic Perma-Flow coronary bypass graft conduit is demonstrated in the first patient at 1-yr follow-up. Coronary blood flow velocity was measured in the body of the graft and into the side-to-side anastomosis to the first diagonal branch. This case report demonstrates the first information on the coronary and prosthetic graft flow in a patient with atherosclerotic coronary disease.


Assuntos
Prótese Vascular , Ponte de Artéria Coronária/métodos , Circulação Coronária/fisiologia , Doença das Coronárias/fisiopatologia , Doença das Coronárias/cirurgia , Idoso , Anastomose Cirúrgica/métodos , Materiais Biocompatíveis/uso terapêutico , Velocidade do Fluxo Sanguíneo , Prótese Vascular/instrumentação , Prótese Vascular/métodos , Cateterismo Cardíaco , Angiografia Coronária , Doença das Coronárias/diagnóstico , Feminino , Humanos
10.
Arch. Inst. Cardiol. Méx ; 67(1): 24-8, ene.-feb. 1997. tab
Artigo em Espanhol | LILACS | ID: lil-195861

RESUMO

De octubre de 1991 a agosto de 1996 fueron implantados 211 coronarios (s) en 166 pacientes (pst) (1.27 s/pt). Ciento treinta y cinco lesiones tratadas fueron de "novo", 44 por resultado sub-óptimo ost-angioplastía, 14 por restenosis y 17 por disección. Angor estable fue el motivo para implante de stent en 36 pst, angor inestable en 68, angor post-infarto en 37, isquemia asintomática post-infarto en 11 e infarto en evolución en otros 14. El tipo de lesiones tratadas fueron en setenta: tipo A, 112 fueron tipo B y 29 fueron tipo C. El grado de severidad de la estenosis pre-procedimiento fue del 85 ñ 15 por ciento. Los tipos de stents utilizados fueron: AVE en 146, Palmaz-Schatz en 33, Wiktor en 23, Gianturco-Roubin en 8 y Wallstent en uno. Medicación post-implante de stent consistió de aspirina y ticlopidina en 140 pts (84.3 por ciento). Los resultados mostraron un éxito técnico del 98.6 por ciento (208/211 pts) y un éxito primario del 94.6 por ciento (157/166 pts). Las complicaciones mayores fueron: oclusión sub-aguda en 3 pts (1.8 por ciento, muerte en 3 pts. (1.8 por ciento) y cirugía de urgencia en un sólo enfermo (0.5 por ciento). Hematoma mayor se presentó en 5 pts (3 por ciento) y el grado de severidad de la estenosis post-implante de stent coronario en nuesto servicio es un procedimiento seguro con una tasa elevada de éxito clínico y con mínimas complicaciones mayores en una población predominante con angor inestable.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Angina Pectoris , Angioplastia Coronária com Balão/efeitos adversos , Prótese Vascular/instrumentação , Prótese Vascular/estatística & dados numéricos , Doença das Coronárias/fisiopatologia , Doença das Coronárias/cirurgia , Infarto do Miocárdio , Resultado do Tratamento
11.
N Engl J Med ; 336(1): 13-20, 1997 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-8970935

RESUMO

BACKGROUND: The treatment of aortic aneurysms with endovascular stents or stent-graft prostheses is receiving increasing attention as an alternative to major abdominal surgery. To define the clinical value of this technique, we prospectively studied the use of stent-graft endoprostheses made of nitinol and covered with polyester fabric for the treatment of infrarenal abdominal aortic aneurysms. METHODS: We treated a total of 154 patients at three academic hospitals. Twenty-one patients with aortic aneurysms not involving the aortic bifurcation received straight stent-grafts, and 133 patients with aortic aneurysms involving the bifurcation and the common iliac arteries received bifurcated stent-grafts. After a unilateral surgical arteriotomy, the endoprostheses were advanced through the femoral arteries and placed under fluoroscopic guidance. Computed tomography and intraarterial angiography were performed during an average follow-up of 12.5 months. RESULTS: The primary success rate, defined as complete exclusion of the abdominal aortic aneurysm from the circulation, was 86 percent in the group receiving straight grafts and 87 percent in the group receiving bifurcated grafts. In three patients the procedure had to be converted to an open surgical operation. Minor (n=13) or major (n=3) complications associated with the procedure (including 1 death) occurred in 10 percent of the patients. All patients had a postimplantation syndrome, with leukocytosis and elevated C-reactive protein levels. CONCLUSIONS: Our results suggest that endovascular treatment of infrarenal abdominal aortic aneurysms is technically feasible and can effectively exclude abdominal aortic aneurysms from the circulation. With further refinement, endoluminal repair may emerge as an interventional strategy to treat infrarenal aortic aneurysms, especially in patients at high surgical risk.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Prótese Vascular/métodos , Stents , Adulto , Idoso , Idoso de 80 Anos ou mais , Ligas , Prótese Vascular/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Poliésteres , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Desenho de Prótese , Resultado do Tratamento
12.
Rev. bras. cir. cardiovasc ; 11(4): 274-8, out.-dez. 1996. ilus
Artigo em Português | LILACS | ID: lil-184578

RESUMO

Introduçao: Após o desenvolvimento de válvula de disco em carbono revestida com material biológico, com bons resultados após dois anos de uso clínico, os autores desenvolveram a primeira válvula brasileira de duplo folheto em carbono. A finalidade foi conseguir uma válvula com baixo nível de ruído, com revestimento de material biológico para facilitar a cicatrizaçao no anel valvar e reduzir ao máximo a superfície sintética exposta ao sangue, para se obterem menores índices de reoperaçao, trombose, tromboembolismo e usar menor dose de anticoagulante a fim de evitar acidentes hemorrágicos. Material e Métodos: A válvula é de duplo folheto com fechamento horizontal e articulado na face interna do corpo, fabricado com Carbolite. É feita em três modelos: toda em carbono semelhante a outras válvulas em uso; revestida com material biológico, ou com batente de elastômero de silicone com revestimento de material biológico. O batente de silicone tem aspecto denteado, para evitar dano ao material biológico e torna a válvula bastante silenciosa. Cada válvula é testada individualmente em acelerador de pulso (1.OOO pulsaçoes por minuto, durante cinco dias) Entao, sao feitos esterilizaçao, revestimento com pericárdio heterólogo processado em glicerina, montagem e esterilizaçao final em gás ETO, sendo conservada em glicerina. Existem 2 pacientes aórticos operados, com dois e três meses de evoluçao, em uso de anticoagulante oral, tendo sido colocadas válvulas apenas com revestimento de material biológico. Resultados Iniciais:Sao poucos casos com pequeno tempo de observaçao, destacando-se boa evoluçao clínica, ausência de percepçao do ruído da válvula e presença do sopro sistólico suave comum em todas as próteses cardíacas aórticas. O modelo com batente de silicone acha-se em teste, nao mostrando desgaste ou dano perceptível, após 30 dias de teste contínuo acelerado já equivalente a 1,4 anos de uso clínico. Conclusoes: A válvula de dois folhetos Biplus apresentou-se com desenho adequado para receber o material biológico e, também, para funcionar com batente de silicone, deixando a válvula bastante silenciosa, para melhor conforto do paciente.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Materiais Biocompatíveis , Prótese Vascular/instrumentação , Carbono , Valvas Cardíacas , Desenho de Prótese , Silicones
13.
ASAIO J ; 42(5): M398-401, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8944915

RESUMO

This article points to the importance of penetrating micropores through the graft wall to minimize thrombosis and to enhance endothelialization in small diameter polymer skin coated vascular grafts. Four types of spongy polyurethane-polydimethylsiloxane vascular grafts (PUG) fabricated by a spray, phase-inversion technique, 1.5 mm inner diameter, 1.5-1.9 cm in length, were implanted end-to-end in the infrarenal aorta of 26 adult rats. Some had a continuous inner skin and a hydraulic permeability (HP) of 0 ml/min/cm2/ 120 mmHg (PUG-S-O). Some had an inner skin with varying amounts of isolated penetrating micropores and a mean hydraulic permeability of 11 (PUG-S-11), 37 (PUG-S-37), or 58 ml/min/cm2/120 mmHg (PUG-S-58). Twelve PUG-S-O, 6 PUG-S-11, 4 PUG-S-11, and 4 PUG-S-58 were evaluated between 2 hr and 3 months after implantation. All PUG-S-O occluded soon after implantation. The PUG that had a HP of more than 11 ml/min/cm2 showed acceptable patency. However, endothelialization was limited to anastomoses in patent PUG-S-11. In contrast, the patent PUG-S-37 and PUG-S-58 were largely endothelialized. In all patent grafts at 3 months, numerous host cells had migrated, and newly formed capillaries were seen in the voids of the graft wall, which appeared moderately to highly cellular. In conclusion, it appears that penetrating micropores through the graft wall increase patency and that a highly porous structure is needed to achieve extensive endothelialization in small diameter polymer skin coated vascular grafts.


Assuntos
Prótese Vascular/instrumentação , Animais , Aorta/cirurgia , Prótese Vascular/efeitos adversos , Dimetilpolisiloxanos , Endotélio Vascular/fisiologia , Estudos de Avaliação como Assunto , Masculino , Microscopia Eletrônica de Varredura , Poliuretanos , Desenho de Prótese , Ratos , Ratos Sprague-Dawley , Silicones , Trombose/etiologia , Trombose/prevenção & controle
14.
ASAIO J ; 42(5): M394-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8944914

RESUMO

The incorporation of a cellular adhesive extracellular matrix and a growth factor into a designed concept for a vital, functioning artificial vascular graft may accelerate tissue regeneration, including endothelialization. Microporous polyurethane grafts (inner diameter, 1.5 mm; wall thickness, 100 microns; length, 20 mm; pore size, 100 microns), fabricated using an excimer laser ablation technique, were coated with a mixed solution of photoreactive gelatin, basic fibroblast growth factor (bFGF), and heparin, and were subsequently photocured by ultraviolet irradiation. Control grafts were treated only with photoreactive gelatin. Both bFGF/heparin impregnated grafts (n = 6) and control grafts (n = 9) were implanted in aortas of rats for 4 weeks. All the implanted grafts were patent when harvested. Endothelialization mainly proceeded from anastomotic sites for both groups. The endothelial coverage in the bFGF/heparin impregnated groups was greater than that in the control animals. At the midportion of the grafts, regenerated endothelial and subendothelial layers were seen for the bFGF/heparin groups, but only fibrin layers were seen for the controls. Thus, coimmobilization of bFGF and heparin significantly enhanced neoarterial wall regeneration through perianastomotic as well as transmural tissue ingrowth. The former was more extensive than the latter.


Assuntos
Prótese Vascular/instrumentação , Fator 2 de Crescimento de Fibroblastos , Animais , Aorta/cirurgia , Endotélio Vascular/fisiologia , Estudos de Avaliação como Assunto , Gelatina , Heparina , Masculino , Microscopia Eletrônica de Varredura , Poliuretanos , Desenho de Prótese , Ratos , Ratos Sprague-Dawley , Regeneração
15.
Am J Surg ; 172(2): 205-9, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8795533

RESUMO

BACKGROUND: The vascular community continues to search for the ideal vascular access graft that will allow early cannulation and avoid temporary central venous catheters. METHODS: This is a review of the Cranley Surgical Associates' experience with the use of the Gore-Tex DIASTAT (W.L. Gore & Associates, Inc., Flagstaff, Arizona) vascular access graft in 20 patients compared with 20 control patients matched for age, sex and risk factors. RESULTS: Although the DIASTAT graft is touted for early accessibility and decreased need for central venous access, that was not found to be the case as 14 patients in the DIASTAT group received temporary access catheters. There was significantly more edema in the DIASTAT patients (P = 0.0048). Comparing the time to the first thrombosis or to revision revealed an average of 18 weeks for the DIASTAT group and 56 weeks for the control group. The length of time to thrombosis or revision was significantly longer in the control group (P = 0.0058). Comparison of the number of weeks of function and serviceability of the grafts revealed the average DIASTAT graft functioned for 34 weeks and that of the control group for an average of 70 weeks (P = 0.0131). Comparison of the two groups showed a significant increase in early thrombotic events (< 90 days) in the DIASTAT grafts (P = 0.0013). CONCLUSIONS: The DIASTAT vascular access graft does not appear to be the ideal hemodialysis access graft.


Assuntos
Prótese Vascular/efeitos adversos , Prótese Vascular/instrumentação , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Politetrafluoretileno , Falha de Prótese , Infecções Relacionadas à Prótese/etiologia , Diálise Renal/métodos , Estudos Retrospectivos , Trombose/etiologia , Fatores de Tempo
16.
Int J Cardiol ; 55(2): 177-81, 1996 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-8842788

RESUMO

Effective orifice area of 3 different designs of prosthetic valves implanted in the aortic position was determined by the continuity equation and the Gorlin formula using Doppler hemodynamic data. The orifice area by the two methods correlated well in the case of tilting disc prostheses (r = 0.75, P = 0.0001, n = 37, SEE = 0.17 cm2) but poorly in the case of bileaflet mechanical valves (r = 0.40, P = 0.17, n = 13) and ball-in-cage prostheses (r = 0.58, P = 0.06, n = 11). Estimation of prosthetic aortic valve area by the Gorlin formula is inappropriate in the latter two types of prostheses because of design-related variable empiric constant.


Assuntos
Valva Aórtica/diagnóstico por imagem , Prótese Vascular/estatística & dados numéricos , Modelos Cardiovasculares , Adolescente , Adulto , Análise de Variância , Valva Aórtica/fisiopatologia , Prótese Vascular/instrumentação , Ecocardiografia Doppler/métodos , Ecocardiografia Doppler/estatística & dados numéricos , Feminino , Hemodinâmica/fisiologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade
17.
Minerva Cardioangiol ; 44(5): 223-7, 1996 May.
Artigo em Italiano | MEDLINE | ID: mdl-8927250

RESUMO

The dilatation of the vascular grafts is a well known phenomenon. It is usually evaluated by means of ultrasounds or, in selected cases, by CT scans or MRI; nevertheless its characteristics are far beyond to be fully recognized. Following our promising preliminary experience with helical CT as sole preoperative imaging for AAA, we have evaluated its reliability in the postoperative follow-up. We have studied 12 patients with aorto-iliac and 11 with aorto-femoral bypass for AAA, with a follow-up ranging between 1 and 3 years. A helical CT acquisition was performed during a single breath-holding with a 5-mm slice thickness, thus resulting in a 30 cm z-axis coverage. Axial images were reconstructed at 2-mm increments and used to generate high quality multiplanar reformatted (MPR) and three-dimensional (3D) surface rendered images. For each patient we evaluated the characteristics of the graft, the maximal diameters and the wall modifications. The average expansion was 28% at 1 year, stable at 2 years and then increased up to 44% at 3 years. Considering the different types of Dacron grafts, the dilatation was ranging between 22% and 46% (21 cases). The mean expansion was 31.3% and 29.5% for the trunk and for the branches of the graft respectively. No perigraft seroma nor anastomotic aneurysms were detected. A peculiar observation, both with and without contrast medium injection, was that all the grafts made on Dacron were not anymore depictable from the aortic wall after 1 year; the contrary was observed for the ePTFE grafts.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Prótese Vascular , Angiografia por Ressonância Magnética , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Aorta Abdominal/cirurgia , Prótese Vascular/instrumentação , Prótese Vascular/métodos , Artéria Femoral/cirurgia , Seguimentos , Humanos , Artéria Ilíaca/cirurgia , Masculino , Cuidados Pós-Operatórios
19.
Plast Reconstr Surg ; 97(3): 662-5, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8596803

RESUMO

Successful implantations of PTFE microvenous prostheses with 3M precise anastomosis systems were presented. Twelve PTFE prostheses (Gore-Tex;I.D.1.0 mm) were implanted into rat femoral veins by means of 3M precise technique to evaluated the patency rate. In the control group, PTFE prostheses (n = 12) were implanted by means of end-to-end technique. In the experimental group, patency of the PTFE prostheses was evaluated at 3 (n = 6) and 6 (n = 6) weeks after implantation by means of macroscopic inspection and scanning electron microscopy. All prostheses except one were patent at the time of removal (patency rate 91.7 percent). All the microvenous prostheses were completely covered by an endothelial layer at 3 and 6 weeks after implantation, and no stenosis was observed at the anastomotic sites. In the control group, all prostheses except one were found to be occluded 3 weeks after implantation. These results demonstrate the value of the 3M precise technique when implanting PTFE microvenous prostheses.


Assuntos
Anastomose Cirúrgica/métodos , Prótese Vascular/instrumentação , Veia Femoral/cirurgia , Microcirculação/cirurgia , Politetrafluoretileno , Anastomose Cirúrgica/instrumentação , Animais , Prótese Vascular/métodos , Masculino , Microcirurgia/instrumentação , Microcirurgia/métodos , Ratos , Ratos Wistar , Fatores de Tempo , Grau de Desobstrução Vascular
20.
Eur J Vasc Endovasc Surg ; 11(2): 214-20, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8616656

RESUMO

OBJECTIVES: To evaluate the early experience with transfemoral endovascular aortic aneurysm management using the Endovascular Grafting System. DESIGN: Multi-centre prospective evaluation of the implantation procedure and early results (median follow-up 153 days). SETTING: Department of Surgery, University Hospital Utrecht, The Netherlands; Department of Surgery, University of Sydney, Australia; University of Leicester School of Medicine, Leicester, U.K., Department of Surgery, Karolinska Hospital, Stockholm, Sweden and Nuffield Department of Surgery, University of Oxford, John Radcliffe Hospital; Oxford, U.K. MATERIALS: 31 consecutive patients treated in 13 months. CHIEF OUTCOME MEASUREMENTS: Peri and postoperative morbidity and mortality in accordance with the recommendations of the Ad Hoc Committee on Reporting Standards. MAIN RESULTS: Graft placement was initially successful in all 31 patients. In one patient the endograft had to be replaced by a standard aortic tube graft because of extra graft flow in the aneurysm sac, and complaints of back pain. One patient died from multiple organ failure, 11 days after the operation. In three patients five severe adverse events were recorded. Breaks of the attachment system were encountered in two patients. These failures did not have severe clinical consequences for individual patients. CONCLUSIONS: Transfemoral Endovascular Aneurysm Management is a technically demanding procedure that requires special training in both catheter and surgical techniques. The potential for less operative morbidity when compared to conventional surgery and the prospect of technical improvements in graft and introduction system design will make TEAM an important tool in aneurysm management in the near future.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Endoscopia/métodos , Idoso , Idoso de 80 Anos ou mais , Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/mortalidade , Prótese Vascular/efeitos adversos , Prótese Vascular/instrumentação , Prótese Vascular/métodos , Endoscópios , Endoscopia/efeitos adversos , Artéria Femoral , Seguimentos , Humanos , Pessoa de Meia-Idade , Polietilenotereftalatos , Complicações Pós-Operatórias/epidemiologia
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