RESUMO
OBJECTIVES: The aim was to compare outcomes of self expanding PTFE covered stents (CSs) with bare metal stents (BMSs) in the treatment of iliac artery occlusions (IAOs). METHODS: Between January 2009 and December 2015, 128 iliac arteries were stented for IAO. A CS was implanted in 78 iliac arteries (61%) and a BMS in 50 (49%). After propensity score matching, 94 limbs were selected and underwent stenting (47 for each group). Thirty day outcomes and midterm patency were compared; follow-up results were analysed with Kaplan-Meier curves. RESULTS: Overall, iliac lesions were classified by limb as TASC B (19%), C (21%), and D (60%). Technical success was 98%. Comparing CS versus BMS, the early cumulative surgical complication rate (12% vs. 12%, p = 1.0) and 30 day mortality rate (2% vs. 2%, p = 1.0) were equivalent. At 36 months (average 23 ± 17), overall primary patency was similar between CS and BMS (87% vs. 66%, p = .06), and this finding was maintained after stratification by TASC B (p = .29) and C (p = .27), but for TASC D, CSs demonstrated a higher patency rate (CS, 88% vs. BMS, 54%; p = .03). In particular, patency was in favour of CSs for IAOs > 3.5 cm in length (p = .04), total lesion length > 6 cm (p = .04), and IAO with calcification > 75% of the arterial wall circumference (p = .01). CONCLUSIONS: Overall, the use of self expanding CS for IAOs has similar early and midterm outcomes compared with BMS. Even if further confirmatory studies are needed, CSs seem to have higher midterm patency rates than BMSs for TASC D lesions, IAOs with a total lesion length > 6 cm, occlusion length > 3.5 cm, and calcification involving > 75% of the arterial wall circumference. These specific anatomical parameters may be useful to the operator when deciding between CS and BMS during endovascular planning.
Assuntos
Ligas , Angioplastia com Balão/instrumentação , Materiais Revestidos Biocompatíveis , Artéria Ilíaca , Doença Arterial Periférica/terapia , Politetrafluoretileno , Stents Metálicos Autoexpansíveis , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Distribuição de Qui-Quadrado , Doença Crônica , Angiografia por Tomografia Computadorizada , Constrição Patológica , Feminino , Humanos , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/fisiopatologia , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Pontuação de Propensão , Desenho de Prótese , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução VascularRESUMO
OBJECTIVES: A straightforward original Chimney Graft (CG) protocol has been developed at our institution in selected cases of juxtarenal aortic aneurysm (JRAA). The aim of this study was to present our clinical experience of consecutive series with use of uncovered self-expanding stent (SES) as "Open Chimney" (OCh) in the endovascular repair (EVAR) of JRAA. METHODS: A standard endograft with suprarenal fixation struts is delivered with its proximal covered edge just below the highest RA in JRAA presenting the ostium of the two renal arteries at a different aortic level and the distance between the highest renal artery and the beginning of the aneurysm (improved landing zone) ≥10 mm. The low-lying renal artery is maintained patent by the OCh graft (standard SES) delivered from left brachial access (6 Fr). All clinical, anatomical, and operative data were prospectively collected and retrieved for the study analysis. RESULTS: From July 2010 to November 2012, OCh EVAR was offered to 22 consecutive patients considered unfit for JRAA open repair. All procedures were technically successful with aneurysm exclusion and patent OCh graft. One small perioperative type Ia endoleak spontaneously disappeared at the 3-month CT control. One patient died because of acute decompensated heart failure. One patient presented a left hemispheric stroke. The median follow-up of 18 months (range 7-35) showed aneurysm exclusion in all patients without type I and III endoleaks, SES stenosis, and/or renal impairment. CONCLUSIONS: OCh-EVAR is a straightforward technique that can be employed in selected cases of JRAA, avoiding the more complex and expensive fenestrated EVAR.
Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/métodos , Procedimentos Endovasculares , Artéria Renal/cirurgia , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/mortalidade , Aortografia/métodos , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Artéria Renal/diagnóstico por imagem , Stents , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
OBJECTIVES: Endovascular treatment of distal abdominal aortic aneurysms (D-AAA) and bilateral common iliac artery aneurysms (BCIAA) may present technical challenges for standard EVAR. Parallel iliac leg endografts (ILEs) of standard aortic devices and covered stents have been successfully employed to treat patients with D-AAA and BCIAA. The perioperative and long-term results of this straightforward endovascular technique are presented. METHODS: Beginning in 2009, patients deemed unfit for open surgery underwent parallel endografts D-AAA and BCIAA exclusion. Avoiding the use of a main body, ILEs are simultaneously delivered from both femoral arteries, landing parallel into the aortic neck (parallel grafts: PG). Distal landing zones including external iliac arteries (EIAs) are reached using appropriate ILEs. A third parallel covered stent graft (Viabahn, Gore) is delivered from a left brachial approach to maintain prograde blood flow to one internal iliac artery (IIA) when needed. RESULTS: Eighteen patients were successfully treated using parallel endografts, nine for BCIAA and nine for D-AAA. All D-AAA presented an irregular saccular shape, including three penetrating aortic ulcers and two pseudoaneurysms of previous aortic grafts. Prograde flow to one IIA was successfully maintained using a Viabahn graft in five patients with BCIAA. Mean aneurysm size was 50 mm in D-AAA and 43 mm in BCIAA. One patient required a perioperative ILE extension to treat a type Ib endoleak. One patient suffered a minor stroke 24 hours after the procedure. Two type II endoleaks were observed postoperatively. Five patients died of non-aneurysm related causes during follow-up. No new endoleaks, graft displacements or occlusions were observed during follow-up (median: 26 months, range 12-42 months). CONCLUSIONS: Successful exclusion of D-AAA and BCIAA was achieved in high-risk patients using parallel endografts, allowing antegrade blood flow to one IIA when needed. Commercially available endografts were used in a simple and effective approach, with excellent follow-up results.
Assuntos
Falso Aneurisma/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Aneurisma Ilíaco/cirurgia , Stents , Úlcera/cirurgia , Idoso , Idoso de 80 Anos ou mais , Falso Aneurisma/diagnóstico , Aneurisma da Aorta Abdominal/diagnóstico , Aortografia/métodos , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Aneurisma Ilíaco/diagnóstico , Masculino , Desenho de Prótese , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Úlcera/diagnósticoRESUMO
The aim of the study was to determine variables that could be used to predict survival in patients with ruptured abdominal aortic aneurysm (RAAA) and to assess the accuracy of the Glasgow Aneurysm Score (GAS) and the Acute Physiology Chronic Health Evaluation II (APACHE-II). From January 1998 to July 2006, 103 patients underwent operations for RAAA. For each patient, 44 variables were retrospectively recorded in a database. Data were analyzed with univariate and multivariate methods. In the univariate analysis significant predictors of death were hypotension (p=0.001), preexisting peripheral vascular disease (p<0.001), renal insufficiency (p=0.037), chronic obstructive pulmonary disease (p=0.028), level of HCO(3)(-) (p<0.001), intraperitoneal rupture (p=0.001), blood transfused (p<0.001), cardiac complications (p<0.001), and APACHE-II score (p=0.001). Multivariate analysis confirmed statistical significance for coexisting peripheral vascular disease (p<0.001), diastolic blood pressure at admission <60 mm Hg (p=0.039), APACHE-II score >18.5 (p=0.025), HCO(3)(-) <21 mg/dL (p<0.001), and intraperitoneal rupture of the aneurysm (p=0.011) as predictors of death. Results of the study suggested that different factors can be helpful in identifying those patients whose operative risk is prohibitive. APACHE-II, contrary to GAS, is an accurate system to predict postoperative death after repair for RAAA.
Assuntos
Aneurisma da Aorta Abdominal/mortalidade , Aneurisma da Aorta Abdominal/cirurgia , Ruptura Aórtica/mortalidade , Ruptura Aórtica/cirurgia , Procedimentos Cirúrgicos Vasculares/mortalidade , APACHE , Idoso , Idoso de 80 Anos ou mais , Feminino , Indicadores Básicos de Saúde , Mortalidade Hospitalar , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
AIM: The aim of this prospective comparative study was to compare the results of 8-years experience of endovascular treatment (ET) of popliteal aneurysms (PAs) using the Hemobahn/Viabahn endograft with those achieved with open repair (OR). Endpoints were primary and secondary patency rate. METHODS: The study was a prospective randomized clinical trial from January 1999 to December 2003 and a prospective comparative study from January 2004 to December 2006. Patients with an asymptomatic aneurismal lesion in the popliteal artery 2 cm at angio-computed tomography were included in the study. Indication for ET was PA (proximal and distal neck length >1 cm); contraindications were: 1) age <50 years; 2) poor distal run-off; 3) contraindication to antiplatelet, anticoagulant or thrombolytic therapy. RESULTS: Between January 1999 and December 2006, of a total of 42 patients with 48 PA, 27 were treated with OR (group A) and 21 with ET (group B). The primary patency rate was 100% in group A and 80.9% in group B at 12 months and 71.4% and 88.1%, respectively, at 72 months; the secondary patency rate at 72 months was 88.15% and 85.9% in groups A and B, respectively. No statistical differences were observed at the log-rank test. During the entire study period, 3 (14.3%) patients in group B required conversion to open surgery because of endograft occlusion. CONCLUSION: Within the power limitations of this study, ET for asymptomatic PA in patients with suitable anatomy can be considered safe, with long-term results comparable with those of OR.
Assuntos
Aneurisma/cirurgia , Implante de Prótese Vascular , Artéria Poplítea/cirurgia , Veia Safena/transplante , Procedimentos Cirúrgicos Vasculares , Idoso , Idoso de 80 Anos ou mais , Aneurisma/diagnóstico , Aneurisma/fisiopatologia , Angiografia Digital , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Politetrafluoretileno , Artéria Poplítea/patologia , Artéria Poplítea/fisiopatologia , Estudos Prospectivos , Desenho de Prótese , Radiografia Intervencionista , Stents , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Grau de Desobstrução Vascular , Procedimentos Cirúrgicos Vasculares/efeitos adversosRESUMO
AIM: The risk for developing stroke increases with the advancing age, peaking over age 80. In elderly patients, carotid endarterectomy may provide prophylaxis against stroke. Aim of our study was to compare patients 80 years or older with patients younger than 80 undergoing carotid endarterectomy. Endpoints were perioperative mortality and morbidity. METHODS: From January 1996 to December 2002, 1 659 patients underwent a 1 733 carotid endarterectomy for a symptomatic or asymptomatic significant carotid lesion. Among them, 125 patients were 80 years or older. We analyzed death and stroke rate from cerebrovascular accidents, TIA as well as non cerebrovascular complications and death rate postoperatively and in the long term follow-up. The Pearson's chi-squared(2) test was used for the statistical analysis on risk factors, morbidity and mortality. The Log rank test was used for cumulative stroke-free and survival rates between the 2 groups (level of confidence p<0.05). RESULTS: Risk factors were similar in both groups. No statistical difference was observed in the stroke, TIA, mortality and stroke free rates between the 2 groups. CONCLUSIONS: The results of our study show that perioperative and postoperative mortality and morbidity as well as the long-term stroke-free rate does not differ significantly in patients 80 years or older compared to patients younger than 80 undergoing carotid endarterectomy.
Assuntos
Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/mortalidade , Ataque Isquêmico Transitório/epidemiologia , Tábuas de Vida , Acidente Vascular Cerebral/epidemiologia , Fatores Etários , Idoso de 80 Anos ou mais , Estenose das Carótidas/diagnóstico , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Taxa de SobrevidaRESUMO
BACKGROUND: The effects of cyclosporin A on accelerated atherosclerosis were studied in an experimental model of aortic isotransplantation. METHODS: Seventy-six Lewis rats were studied. Forty-one abdominal aortic isografts were performed and divided into five groups: 2-day isografts and 15- and 100-day isografts with and without cyclosporin treatment. The remaining rats were divided into seven groups: 15- and 100-day sham-operated, with and without cyclosporin administration; 15- and 100-day animals with cyclosporin treatment only; and normal controls. Cyclosporin was injected subcutaneously in doses of 10 mg/kg daily for the first 15 days and afterward every other day. Longitudinal sections of the proximal anastomosis and cross sections of the midgraft region were measured with a semiautomatic image-analyzer. RESULTS: Histologic analysis showed that accelerated atherosclerosis was not observed either in NT2 rats or in nontransplanted animals. In the 15-day isografts, accelerated atherosclerosis was present in the perianastomotic tract of the recipient aorta in nine of nine NT15 rats, whereas it was found only in three of nine T15 animals (p < 0.02). Histomorphometric analysis showed that accelerated atherosclerosis was less pronounced in the T100 isografts than in the NT100 ones, this difference being significant at the recipient anastomotic side only (p < 0.0005). CONCLUSIONS: The present results support the hypothesis that cyclosporin, at immunosuppressant and nontoxic doses, can delay the onset and progression of accelerated atherosclerosis and that its effects are more significant at the recipient side of the anastomosis where accelerated atherosclerosis begins to develop.
Assuntos
Aorta Abdominal/transplante , Arteriosclerose/induzido quimicamente , Ciclosporina/toxicidade , Imunossupressores/toxicidade , Transplante de Pulmão/patologia , Anastomose Cirúrgica , Animais , Aorta Abdominal/patologia , Arteriosclerose/patologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Injeções Subcutâneas , Masculino , Ratos , Ratos Endogâmicos Lew , Transplante IsogênicoRESUMO
BACKGROUND: The purpose of this study was to determine the correlation between progression and regression of myointimal hyperplasia (MH) and cytokine production in experimental vein grafts. Although the autologous vein is the best suitable bypass conduit for reconstruction of peripheral arteries, at the end of the first year thrombosis in the coronary and lower extremity circulation ranges from 20% to 50%. Many of these failures are caused by MH. METHODS: In 76 inbred Lewis rats, a 1 cm long segment of inferior vena cava was inserted at the level of the abdominal aorta. The segments of inferior vena cava were obtained from syngeneic Lewis rats. In 56 animals the arterial vein graft was explanted 3 days (n = 10), 7 days (n = 10), 4 weeks (n = 26), and 12 weeks (n = 10) after operation. In 20 animals the vein graft was explanted 4 weeks after being in the arterial system and reimplanted as iliac venovenous bypass in syngeneic Lewis rats. These grafts were explanted 2 weeks (n = 10) and 8 weeks (n = 10) later. Grafts were analyzed by light and electron microscopy, morphometric study, and histochemical analysis and were put in an organ culture to assess cytokine production. RESULTS: We observed MH formation in arterial vein grafts and MH regression in reimplanted vein grafts (p < 0.001). MH formation was correlated with production of platelet-derived growth factor, basic fibroblast growth factor, interleukin-1, and tumor necrosis factor-alpha. MH regression was correlated with transforming growth factor-beta 1 production. CONCLUSIONS: On the basis of the results of our study, we conclude that MH formation in experimental vein grafts depends on production of platelet-derived growth factor, basic fibroblast growth factor, interleukin-1, and tumor necrosis factor-alpha, and MH regression depends on transforming growth factor-beta 1 production. Cytokine therapy may represent a valuable new treatment to prevent vein bypass failures caused by MH.
Assuntos
Citocinas/biossíntese , Túnica Íntima/fisiologia , Veia Cava Inferior/fisiologia , Animais , Aorta Abdominal , Hiperplasia , Interleucina-1/biossíntese , Masculino , Técnicas de Cultura de Órgãos , Fator de Crescimento Derivado de Plaquetas/biossíntese , Ratos , Ratos Endogâmicos Lew , Fator de Crescimento Transformador beta/biossíntese , Transplante Heterólogo , Transplante Isogênico , Fator de Necrose Tumoral alfa/biossíntese , Túnica Íntima/imunologia , Túnica Íntima/patologia , Procedimentos Cirúrgicos Vasculares , Veia Cava Inferior/imunologia , Veia Cava Inferior/transplanteRESUMO
BACKGROUND: The aim of the study was to compare two of the available cerebral protection devices (CPD) PercuSurge, balloon type (group A) and Angioguard, filter type (group B) used in carotid stenting and angioplasty (CAS). METHODS: From September 1999 to February 2001, 26 consecutive patients undergoing CAS were alternatively assigned to group A and B. Postoperative disabling stroke and neurological mortality, nondisabling stroke, TIA and non-neurological mortality were examined. CPD features included time required, ease of handling, device rupture or malfunctioning, radiopaque markers evidence, abnormal major mobility of the opened system. RESULTS: RNCR was 0 and TIAs were not observed in either group. Four patients (3 in group A and 1 in group B) showed drowsiness in the immediate postoperative period. Perioperative carotid occlusion and surgical conversion were observed in 1 case of group A. Average time calculated from the beginning of set-up to complete removal was 46 min in group A versus 31 min in group B. Abnormal major mobility of the opened system was very often observed during endovascular maneuvers with both devices. CONCLUSIONS: CAS may protect against postoperative procedure-related neurological events. Common and specific disadvantages were observed in both systems showing they were not close enough to the ideal device.
Assuntos
Complicações Pós-Operatórias/prevenção & controle , Acidente Vascular Cerebral/prevenção & controle , Idoso , Angioplastia com Balão , Estenose das Carótidas/cirurgia , Circulação Cerebrovascular , Desenho de Equipamento , Feminino , Humanos , Masculino , Estudos Prospectivos , Stents , Fatores de TempoRESUMO
AIM: Elongation and tortuosity of the internal carotid artery (ICAET) is a common angiographic, angioMR or Duplex scanning finding: it can be "pure" and, in a great majority of cases, it is not correlated to neurological symptoms. It can be associated with atherosclerotic bifurcation plaque, therefore in this case, indications to surgery follow that of carotid stenosis. On the other hand in some patients ICAET seems potentially correlated to hemispheric or non hemispheric symptoms: ICAET may show as kinking with a wide or narrow acute angle, single (< shaped) or double (Z shaped), or less frequently as a coiling (S,U, or C shaped). Surgical indications are controversial. In the author's opinion, surgery may represent the safest tool in the prevention of a stroke due to carotid occlusion, in selected patients. The aim of this study is to describe the author's experience in the surgical treatment of carotid kinking not associated with significant atherosclerotic lesions. METHODS: From March 1994 to March 2001, 29 patients (11 male, 18 female) with a pure ICAET underwent surgery. Patients presented hemispheric symptoms (24.13%), non hemispheric symptoms (41.3%) or both (27.5 %). Two asymptomatic patients (6.9%) underwent surgery because of contralateral carotid occlusion. RESULTS: The postoperative (within 30 days from operation) results, no mortality was observed, 1 patient presented a stroke (3.4%), and 1 patient had a TIA at awakening (negative cerebral CT scan). All patients with hemispheric symptoms (15 patients) had complete remission, whereas only 6 out of 12 patients (50%) presenting non-hemispheric symptoms had remission (1 patient underwent a controlateral ICAET correction). CONCLUSIONS: The natural history of symptomatic and asymptomatic ICAET is practically unknown, but in some cases selected indication to surgery is justified. Surgery was indicated for patients with transient ischaemic attacks ( hemispheric symptoms); in asymptomatic patients presenting a kinking with an angle inferior to 30 degrees, and a contralateral carotid artery occlusion; in patients with non hemispheric symptoms, after a screening to exclude all other possible neurological or non-neurological causes with duplex scan positive for significant increase of flow velocity in ICA and positive cerebral CT scan or MR scan for ischaemic lesions in the homolateral hemisphere, and/or a flow inversion in anterior cerebral artery or flow reduction in the middle cerebral artery, according to different head positions (rotation and flex-extension).
Assuntos
Doenças das Artérias Carótidas/cirurgia , Artéria Carótida Interna/anormalidades , Artéria Carótida Interna/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Idoso , Anastomose Cirúrgica/métodos , Angiografia Digital , Isquemia Encefálica/etiologia , Isquemia Encefálica/prevenção & controle , Doenças das Artérias Carótidas/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
Myelolipoma is a rare benign neoplasm of the adrenal gland, histologically characterized by the presence of mature fat cells and bone marrow elements. In the international literature were reported 126 cases of adrenal myelolipoma surgically treated. The indications to surgical removal of this tumor are the presence of large symptomatic tumours, high risk of spontaneous haemorrhage, and suspicion of malignant neoplasms. The authors present a case of adrenal myelolipoma, preoperatively identified with an abdominal MNR, and surgically removed.
Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Lipoma/diagnóstico , Neoplasias das Glândulas Suprarrenais/patologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/patologia , Adrenalectomia , Humanos , Lipoma/patologia , Lipoma/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , UltrassonografiaRESUMO
The Authors report a case of leiomyoma located in an epi-phrenic diverticulum. The development of the leiomyoma may have weakened the esophageal wall and caused the diverticulum to appear. Surgical treatment consisted of diverticulectomy with myotomy and a Belsey MK IV antireflux procedure.
Assuntos
Divertículo Esofágico/etiologia , Neoplasias Esofágicas/complicações , Leiomioma/complicações , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
The widespread use of graft replacement material led to complications inherent to these prostheses with increasing frequency. The discussion is still open on identifying those inherent features of vascular grafting that could contribute to long term success or short term failure. The search has been prompted for better arterial substitutes, among others, for repair particularly of lesions of smaller arteries. The ideal graft should have an innately blood-compatible flow surface with fixed endothelium and basement membrane and innately physiological mechanical properties. There are a number of biological and plastic materials competing for this goals. All plastic materials studied in clinical trials so far stimulate an uncontrollable proliferative response in host arteries behind or in the distal anastomosis; such causes failure of grafts when of small caliber. This distal anastomotic subintimal hyperplasia (SIH) is an ubiquitous pathologic entity in late graft occlusion. The cause of SIH has been the subject of much investigation. The role of compliance mismatch between host artery and vascular grafts in the development of SIH is discussed in this paper. While compliance may, in fact, be an important parameter in determining the results of bypass grafting, the dominant influence of hemodynamic and thrombogenic factors has continued to mask what is probably a very subtle effect. Summarizing the current knowledge it is likely that match or mismatch between the anisotropic behavior of the host artery and the linear respectively nonlinear response to varying blood pressure of the graft influences patency results. Any mismatch in tubular compliance in a quantitative manner will contribute to the long-term results but in a lesser degree. Disturbance of the biomechanical properties of the arterial tree due to an vascular anastomosis seems to be of utmost importance to the outcome, but up to now we were not able to demonstrate a link conclusively between compliance mismatch and the occurrence of subintimal hyperplasia. The present results imply a major impact on future graft design and the development of better anastomotic techniques, because compliance is a critical parameter for maintenance of arterial reconstructions.
Assuntos
Prótese Vascular , Anastomose Cirúrgica , Artérias/fisiologia , Fenômenos Biomecânicos , Pressão Sanguínea , Complacência (Medida de Distensibilidade) , Humanos , Fatores de Tempo , Grau de Desobstrução VascularRESUMO
The authors present their experience with abdominal aortic aneurysm during the last 12 years. From 1976 up to now they treated 70 patients with abdominal aortic aneurysms. Sixty-seven patients (96%) were male, while 3 (4%) female. Mean age was 65 years (S.D. +/- 7.97). 82% of the patients were heavy smokers. Sixty-five patients were treated by means of resection and vascular reconstruction. Their associated pathologies were: M.I. or severe heart ischemia 34 (52.3%), diabetes 13 (20%), hypertension 25 (38.4%), T.I.A. 6 (9.2%), renal insufficiency 13 (20%), and respiratory insufficiency 18 (27.6%). Results demonstrated a 12-year patency rate of 91.8%. Five high-risk patients were treated by means of "palliative" treatment. Associated pathologies and risk factors were: smoking 5 (100%), M.I. or severe heart ischemia 5 (100%), diabetes 2 (40%), hypertension 4 (80%), T.I.A. 2 (40%), renal insufficiency 2 (40%), respiratory insufficiency 3 (60%). Treatment consisted in the sac thrombosis by means of Gianturco-Wallace coils into the aneurysm (2 cases) and iliac artery ligation (3 cases). Both techniques allowed acute thrombosis of the aneurysm. Vascular supply to the lower limbs was performed by means of an axillo-bifemoral reconstruction in all cases. Long-term prognosis of these five patients was poor due to their general condition.
Assuntos
Aneurisma Aórtico/cirurgia , Idoso , Idoso de 80 Anos ou mais , Aorta Abdominal/cirurgia , Aneurisma Aórtico/terapia , Embolização Terapêutica , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To determine the predictor factors of in-hospital postoperative mortality in patients presenting with symptomatic but not ruptured abdominal aortic aneurysm (AAA) at our institution. PATIENTS AND METHODS: Forty-two patients who underwent urgent open repair for symptomatic, non-ruptured AAA were evaluated retrospectively. RESULTS: Five patients (11.9%) died during the in-hospital stay. History of coronary artery disease (p=0.014), cerebrovascular diseases (p=0.015), renal failure according to Glasgow Aneurysm Score (GAS) criteria (p=0.001), serum creatinine concentration (p=0.026), and the GAS (p=0.008) were predictive of postoperative death. The ROC curve analysis showed that the Glasgow Aneurysm Score had an area under the curve of 0.870 (95%C.I. 0.71-1, S.E. 0.08, p=0.008), and its best cut-off value in predicting postoperative death was 90.0 (specificity 89.2%, sensitivity 80.0%). The postoperative mortality rate of patients with a Glasgow Aneurysm Score below 90 was 2.9%, whereas it was 50% for those with a score >or=90 (p=0.003, O.R. 33.0). CONCLUSION: This study shows that the Glasgow Aneurysm Score is a good predictor of postoperative mortality and morbidity after urgent repair of symptomatic, non-ruptured AAA and can be useful in identifying those patients whose operative risk is prohibitive. Its simplicity makes it a clinically important tool, particularly, in the emergency setting. Patients having a score less than 90 can safely undergo urgent open repair. Thorough evaluation and improvement of preoperative status followed preferably by an endovascular repair is indicated for those with a score >or=90.