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1.
Eur J Vasc Endovasc Surg ; 60(5): 663-670, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32855029

RESUMO

OBJECTIVE: Iliac limb occlusion (ILO) is a complication of endovascular aortic repair (EVAR) and requires re-intervention in most cases. Attention to any intra-operative defect of iliac limbs and arteries may prevent ILO. The study aimed to analyse the long term effect of an intra-operative protocol of iliac limb treatment during EVAR on ILO. METHODS: Patients treated from 2012 to 2017 for abdominal aortic aneurysm (AAA) with standard EVAR were collected prospectively. Pre-operative computed tomography angiography anatomical characteristics were evaluated. The protocol for intra-operative iliac limb management was: a. pre-EVAR angioplasty of common/external iliac artery stenosis; b. precise contralateral iliac limb deployment at the same level of the flow divider; c. iliac limb kissing ballooning with high pressure non-compliant balloons; d. iliac limb stenting for residual tortuosity/kink and adjunctive external iliac stenting for residual stenosis/dissection after EVAR. ILO was evaluated at 30 days and at follow up, which was performed by duplex ultrasonography before discharge, at three, six, and 12 months and yearly thereafter. Kaplan-Meier and Cox linear regression were used. RESULTS: Four hundred and forty-two patients and 884 iliac limbs were included in the study. Severe iliac tortuosity and calcification were present in 15% (132/884) and 8% (70/884), respectively. External iliac angioplasty and stenting of iliac limb were performed in 2% (18/884) and 9.5% (84/884) of limbs. The thirty day mortality was 1.6%, with no ILO. At a mean follow up of 33 ± 12 months, ILO occurred in 7/884 (0.8%) limbs of six patients. Five ILO were treated by endovascular relining, two surgically: one by femorofemoral bypass and one by surgical explant. On univariable analysis, sac shrinkage was significantly associated with ILO (HR 1, 95% CI 0.8-2.5, p = .043). CONCLUSION: A protocol of aggressive iliac limb treatment in EVAR leads to a very low rate of late ILO. The role of sac shrinkage in ILO should be investigated further.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Oclusão de Enxerto Vascular/prevenção & controle , Artéria Ilíaca/cirurgia , Cuidados Intraoperatórios/normas , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/mortalidade , Protocolos Clínicos , Angiografia por Tomografia Computadorizada , Feminino , Seguimentos , Oclusão de Enxerto Vascular/epidemiologia , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/cirurgia , Mortalidade Hospitalar , Humanos , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/patologia , Cuidados Intraoperatórios/métodos , Estimativa de Kaplan-Meier , Masculino , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Stents/efeitos adversos , Resultado do Tratamento , Grau de Desobstrução Vascular
2.
Microvasc Res ; 131: 104027, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32505610

RESUMO

Cardiovascular diseases, among all diseases, are taking the most victims worldwide. Coronary artery occlusion, takes responsibility of about 30% of the yearly global deaths in the world (Heart Disease and Stroke Statistics 2017 At-a-Glance, 2017), raising the need for viable substitutes for cardiovascular tissues. Depending on a number of factors, blocked coronary arteries are now being replaced by autografts or stents. Since the autografts, as the gold standard coronary artery replacements, are not available in adequate quality and quantity, the demand for small diameter vascular substitute comparable to native vessels is rapidly growing. Synthetic grafts have been successfully approved for developing vascular replacements but regarding the special conditions in small-caliber vessels, their use is limited to large-diameter vascular tissue engineering. The major problems associated with the vascular tissue engineered grafts are thrombosis and intimal hyperplasia. Heparin, a negatively charged natural polysaccharide has been used in fabricating vascular grafts since it prevents protein fouling on the surfaces and most importantly, impeding thrombosis. Herein, we focused on heparin, as a multifunctional bioactive molecule that not only serves as an anticoagulant with frequent clinical use but also acts as an anti-inflammatory and angiogenic regulatory substance. We summarized heparin incorporation into stents and grafts and their applicability to restrain restenosis. Also, the applications of heparinzation of biomaterials and heparin mimetic polymers and different approaches invoked to improve heparin bioactivity have been reviewed. We summarized the methods of adding heparin to matrices as they were explained in the literature. We reviewed how heparin influences the biocompatibility of the scaffolds and discussed new advances about using heparin in small-diameter vascular tissue engineering.


Assuntos
Anticoagulantes/uso terapêutico , Bioprótese , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Oclusão de Enxerto Vascular/prevenção & controle , Heparina/uso terapêutico , Stents , Trombose/prevenção & controle , Engenharia Tecidual , Animais , Anticoagulantes/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Heparina/efeitos adversos , Humanos , Desenho de Prótese , Trombose/etiologia , Trombose/fisiopatologia , Grau de Desobstrução Vascular
3.
PLoS One ; 15(6): e0235168, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579611

RESUMO

OBJECTIVE: There is an increasing need for small diameter vascular grafts with superior host hemo- and cytocompatibilities, such as low activation of platelets and leukocytes. Therefore, we aimed to investigate whether the preparation of bacterial nanocellulose grafts with different inner surfaces has an impact on in vitro host cytocompatibility. METHODS: We have synthesized five different grafts in a bioreactor, namely open interface surface (OIS), inverted (INV), partially air dried (PAD), surface formed in air contact (SAC) and standard (STD) that were characterized by a different surface roughness. The grafts (length 55 mm, inner diameter 5 mm) were attached to heparinized polyvinyl chloride tubes, loaded with human blood and rotated at 37°C for 4 hours. Then, blood was analyzed for frequencies of cellular fractions, oxidative products, soluble complement and thrombin factors. The results were compared to clinically approved grafts made of polyethylene terephthalate and expanded polytetrafluoroethylene. Additionally, blood platelets were labelled with 111Indium-oxine to visualize the distribution of adherent platelets in the loop by scintigraphy. RESULTS: SAC nanocellulose grafts with the lowest surface roughness exhibited superior performance with <10% leukocyte and <50% thrombocyte loss in contrast to other grafts that exhibited >65% leukocyte and >90% thrombocyte loss. Of note, SAC nanocellulose grafts showed lowest radioactivity with scintigraphy analyses, indicating reduced platelet adhesion. Although the levels of reactive oxygen species and cell free DNA did not differ significantly, the levels of thrombin-antithrombin complexes were lowest in SAC grafts. However, all nanocellulose grafts exhibited enhanced complement activation. CONCLUSION: The systematic variation of the inner surfaces of BNC vascular grafts significantly improves biocompatibility. Especially, SAC grafts exhibited the lowest loss of platelets as well as leukocytes and additionally significantly diminished activation of the coagulation system. Further animal studies are needed to study in vivo biocompatibilities.


Assuntos
Materiais Biocompatíveis/química , Prótese Vascular , Celulose/química , Polissacarídeos Bacterianos/química , Grau de Desobstrução Vascular/fisiologia , Animais , Coagulação Sanguínea/efeitos dos fármacos , Implante de Prótese Vascular/métodos , Celulose/ultraestrutura , Oclusão de Enxerto Vascular/fisiopatologia , Oclusão de Enxerto Vascular/prevenção & controle , Heparina/farmacologia , Humanos , Teste de Materiais/métodos , Microscopia Eletrônica de Varredura , Adesividade Plaquetária/fisiologia , Polietilenotereftalatos/química , Politetrafluoretileno/química , Propriedades de Superfície , Grau de Desobstrução Vascular/efeitos dos fármacos
4.
Vascular ; 28(6): 765-774, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32408854

RESUMO

BACKGROUND: The major mechanisms of arteriovenous graft (AVG) failure due to intimal hyperplasia (IH) are smooth muscle cell proliferation and inflammation. Therefore, carvedilol may improve AVG primary patency because of its anti-proliferative and anti-inflammatory activities. METHODS: The data of end-stage renal disease patients receiving regular hemodialysis were collected from the National Health Insurance Research database. The end point was the first percutaneous transluminal angioplasty (PTA) for AVG failure or death during a follow-up period of two years or the end of 2013. The analysis was calculated with Cox proportional hazard model. RESULTS: There were 3028 patients treated with carvedilol and 13,704 patients not treated with carvedilol. According to a univariate analysis, the carvedilol group was younger, received more anti-hypertensive medications and platelet aggregation inhibitors, and had higher rates of diabetes mellitus and hyperlipidemia but had lower rates of hypotension and smoking. According to a multivariate analysis, after controlling for covariates, the use of carvedilol for more than 84 days reduced the probability of a first PTA for AVG failure by 9% compared with no use of carvedilol (p = 0.021), but the use of carvedilol for 1 to 84 days did not. CONCLUSION: The results of this study indicate that the use of carvedilol for more than 84 days improves the primary patency of AVGs, but the use of carvedilol for less than 84 days does not.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/administração & dosagem , Derivação Arteriovenosa Cirúrgica , Carvedilol/administração & dosagem , Oclusão de Enxerto Vascular/prevenção & controle , Falência Renal Crônica/terapia , Diálise Renal , Grau de Desobstrução Vascular/efeitos dos fármacos , Antagonistas de Receptores Adrenérgicos alfa 1/efeitos adversos , Idoso , Angioplastia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Carvedilol/efeitos adversos , Bases de Dados Factuais , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Falência Renal Crônica/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Taiwan , Fatores de Tempo , Resultado do Tratamento
5.
J Card Surg ; 35(6): 1314-1321, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32353909

RESUMO

BACKGROUND: The saphenous vein remains the most frequently used conduit for coronary artery bypass grafting, despite reported unsatisfactory long-term patency rates. Understanding the pathophysiology of vein graft failure and attempting to improve its longevity has been a significant area of research for more than three decades. This article aims to review the current understanding of the pathophysiology and potential new intervention strategies. METHODS: A search of three databases: MEDLINE, Web of Science, and Cochrane Library, was undertaken for the terms "pathophysiology," "prevention," and "treatment" plus the term "vein graft failure." RESULTS: Saphenous graft failure is commonly the consequence of four different pathophysiological mechanisms, early acute thrombosis, vascular inflammation, intimal hyperplasia, and late accelerated atherosclerosis. Different methods have been proposed to inhibit or attenuate these pathological processes including modified surgical technique, topical pretreatment, external graft support, and postoperative pharmacological interventions. Once graft failure occurs, the available treatments are either surgical reintervention, angioplasty, or conservative medical management reserved for patients not eligible for either procedure. CONCLUSION: Despite the extensive amount of research performed, the pathophysiology of saphenous vein graft is still not completely understood. Surgical and pharmacological interventions have improved early patency and different strategies for prevention seem to offer some hope in improving long-term patency.


Assuntos
Ponte de Artéria Coronária/métodos , Doença da Artéria Coronariana/cirurgia , Oclusão de Enxerto Vascular/prevenção & controle , Oclusão de Enxerto Vascular/terapia , Disfunção Primária do Enxerto/prevenção & controle , Disfunção Primária do Enxerto/terapia , Veia Safena/transplante , Enxerto Vascular/métodos , Oclusão de Enxerto Vascular/etiologia , Humanos , Disfunção Primária do Enxerto/etiologia , Resultado do Tratamento , Grau de Desobstrução Vascular
7.
PLoS One ; 15(4): e0231463, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32287283

RESUMO

BACKGROUND: Restenosis remains a significant problem in endovascular therapy for hemodialysis vascular access. Drug-coated balloon (DCB) angioplasty decreases restenosis in peripheral and coronary artery diseases. The aim of this systematic review and meta-analysis is to assess the patency outcomes following DCB angioplasty, as compared to conventional balloon (CB) angioplasty for the stenosis of hemodialysis vascular access. METHODS: A comprehensive search in the MEDLINE, EMBASE, and CENTRAL databases was conducted in order to identify eligible randomized controlled trials evaluating DCB angioplasty for hemodialysis vascular access dysfunction. The primary endpoint was the 6-month target lesion primary patency and the secondary endpoints were 12-month target lesion primary patency and procedure-related complications. Risk ratios (RR) were pooled and relevant subgroups were analyzed separately. RESULTS: Eleven randomized controlled trials comprised of 487 patients treated with DCB angioplasty and 489 patients treated with CB angioplasty were included. There were no significant differences in the target lesion primary patency at 6 months [RR, 0.75; 95% confidence interval (CI), 0.56, 1.01; p = 0.06] and at 12 months (RR 0.89; 95% CI, 0.79, 1.00; p = 0.06). The absence of benefit for the DCB group remained, even in the arteriovenous fistula subgroup or the subgroup of studies excluding central vein stenosis. The risk of procedure-related complication did not differ between the two groups (RR 1.00; 95% CI 0.98, 1.02; p = 0.95). CONCLUSION: DCB angioplasty did not demonstrate significant patency benefit for the treatment of hemodialysis vascular access dysfunction. Wide variations in patency outcomes across studies were noted. Further studies focusing on specific types of access or lesions are warranted to clarify the value of DCB for hemodialysis vascular access. (PROSPERO Number CRD42019119938).


Assuntos
Angioplastia com Balão/métodos , Fístula Arteriovenosa/terapia , Oclusão de Enxerto Vascular/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Fístula Arteriovenosa/fisiopatologia , Fármacos Cardiovasculares/efeitos adversos , Materiais Revestidos Biocompatíveis/efeitos adversos , Materiais Revestidos Biocompatíveis/uso terapêutico , Constrição Patológica/fisiopatologia , Feminino , Artéria Femoral/fisiopatologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/fisiopatologia , Artéria Poplítea/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Diálise Renal/métodos , Fatores de Tempo , Resultado do Tratamento , Dispositivos de Acesso Vascular , Grau de Desobstrução Vascular
8.
Am Heart J ; 224: 17-24, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32272256

RESUMO

The SWEDEGRAFT study (ClinicalTrials.gov Identifier: NCT03501303) tests the hypothesis that saphenous vein grafts (SVGs) harvested with the "no-touch" technique improves patency of coronary artery bypass grafts compared with the conventional open skeletonized technique. This article describes the rationale and design of the randomized trial and baseline characteristics of the population enrolled during the first 9 months of enrollment. The SWEDEGRAFT study is a prospective, binational multicenter, open-label, registry-based trial in patients undergoing first isolated nonemergent coronary artery bypass grafting (CABG), randomized 1:1 to no-touch or conventional open skeletonized vein harvesting technique, with a planned enrollment of 900 patients. The primary end point is the proportion of patients with graft failure defined as SVGs occluded or stenosed >50% on coronary computed tomography angiography at 2 years after CABG, earlier clinically driven coronary angiography demonstrating an occluded or stenosed >50% vein graft, or death within 2 years. High-quality health registries and coronary computed tomography angiography are used to assess the primary end point. The secondary end points include wound healing in the vein graft sites and the composite outcome of major adverse cardiac events during the first 2 years based on registry data. Demographics of the first 200 patients enrolled in the trial and other CABG patients operated in Sweden during the same time period are comparable when the exclusion criteria are taken into consideration. RCT# NCT03501303.


Assuntos
Doença da Artéria Coronariana/cirurgia , Oclusão de Enxerto Vascular/prevenção & controle , Sistema de Registros , Veia Safena/transplante , Coleta de Tecidos e Órgãos/métodos , Idoso , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico , Feminino , Seguimentos , Oclusão de Enxerto Vascular/diagnóstico , Humanos , Masculino , Estudos Prospectivos , Resultado do Tratamento
9.
Surg Technol Int ; 35: 197-201, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32120449

RESUMO

INTRODUCTION: Progressive saphenous vein graft (SVG) failure remains a key limitation to the long-term success of coronary artery bypass grafting (CABG). SVG disease after the first year is dominated by intimal hyperplasia, which predisposes the SVG to thrombosis and accelerated atherosclerosis. The objective of this study was to review and summarize the latest experimental and clinical data on the use of mechanical external stents for vein grafts. METHODS: In January 2020, the PubMed database was searched using the terms "external stent", "CABG", "saphenous vein graft" and "intimal hyperplasia". The results were reviewed and only randomized experimental and clinical studies that analyzed the effect of external stenting on venous intimal hyperplasia were included in the analysis, together with studies that investigated the clinical benefit of external stenting. RESULTS: Eight experimental and four clinical trials met the search criteria. Controlled trials in different large animal models concluded that external stenting significantly reduced intimal hyperplasia 3-6 months post implantation, and reduced both thrombosis rates and the development of lumen irregularities. Data from randomized controlled trials with a follow-up period of 1-4.5 years supported the pre-clinical findings and demonstrated that external stents significantly reduced vein graft disease. CONCLUSION: Strong evidence indicates that supporting the vein with external stents is safe and leads to clear advantages at both the anatomical and cellular levels. With the further accumulation of consistent positive results, external stenting of SVG may become the standard of care in future CABG.


Assuntos
Ponte de Artéria Coronária/métodos , Oclusão de Enxerto Vascular/prevenção & controle , Veia Safena/transplante , Stents , Túnica Íntima/patologia , Animais , Aterosclerose/etiologia , Aterosclerose/prevenção & controle , Implante de Prótese Vascular/métodos , Oclusão de Enxerto Vascular/etiologia , Humanos , Hiperplasia/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Veia Safena/cirurgia , Trombose/etiologia , Trombose/prevenção & controle , Túnica Íntima/cirurgia , Grau de Desobstrução Vascular
10.
Am J Cardiol ; 125(4): 491-499, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31889527

RESUMO

Incidence and predictors of adverse events after dual antiplatelet therapy (DAPT) cessation in patients treated with thin stents (<100 microns) in unprotected left main (ULM) or coronary bifurcation remain undefined. All consecutive patients presenting with a critical lesion of an ULM or involving a main coronary bifurcation who were treated with very thin strut stents were included. MACE (a composite end point of cardiovascular death, myocardial infarction [MI], target lesion revascularization [TLR], and stent thrombosis [ST]) was the primary endpoint, whereas target vessel revascularization (TVR) was the secondary endpoint, with particular attention to type and occurrence of ST and occurrence of ST, CV death, and MI during DAPT or after DAPT discontinuation. All analyses were performed according to length of DAPT dividing the patients in 3 groups: Short DAPT (3-months), intermediate DAPT (3 to 12 months), and long DAPT (12-months). A total of 117 patients were discharged with an indication for DAPT ≤3 months (median 1: 1 to 2.5), 200 for DAPT between 3 and 12 months (median 8: 7 to 10), and 1,958 with 12 months DAPT. After 12.8 months (8 to 20), MACE was significantly higher in the 3-month group compared with 3 to 12 and 12-month groups (9.4% vs 4.0% vs 7.2%, p ≤0.001), mainly driven by MI (4.4% vs 1.5% vs 3%, p ≤0.001) and overall ST (4.3% vs 1.5% vs 1.8%, p ≤0.001). Independent predictors of MACE were low GFR and a 2 stent strategy. Independent predictors of ST were DAPT duration <3 months and the use of a 2-stent strategy. In conclusion, even stents with very thin strut when implanted in real-life ULM or coronary bifurcation patients discharged with short DAPT have a relevant risk of ST, which remains high although not significant after DAPT cessation.


Assuntos
Doença da Artéria Coronariana/terapia , Terapia Antiplaquetária Dupla/efeitos adversos , Stents , Idoso , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Feminino , Oclusão de Enxerto Vascular/prevenção & controle , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo
11.
Cardiovasc Res ; 116(3): 505-519, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31397850

RESUMO

Coronary artery disease (CAD) remains one of the most important causes of morbidity and mortality worldwide, and the availability of percutaneous or surgical revascularization procedures significantly improves survival. However, both strategies are daunted by complications which limit long-term effectiveness. In-stent restenosis (ISR) is a major drawback for intracoronary stenting, while graft failure is the limiting factor for coronary artery bypass graft surgery (CABG), especially using veins. Conversely, internal thoracic artery (ITA) is known to maintain long-term patency in CABG. Understanding the biology and pathophysiology of ISR and vein graft failure (VGF) and mechanisms behind ITA resistance to failure is crucial to combat these complications in CAD treatment. This review intends to provide an overview of the biological mechanisms underlying stent and VGF and of the potential therapeutic strategy to prevent these complications. Interestingly, despite being different modalities of revascularization, mechanisms of failure of stent and saphenous vein grafts are very similar from the biological standpoint.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Doença da Artéria Coronariana/terapia , Reestenose Coronária/prevenção & controle , Vasos Coronários/cirurgia , Oclusão de Enxerto Vascular/prevenção & controle , Artéria Torácica Interna/cirurgia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Veia Safena/transplante , Stents , Animais , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/fisiopatologia , Reestenose Coronária/metabolismo , Reestenose Coronária/patologia , Reestenose Coronária/fisiopatologia , Vasos Coronários/metabolismo , Vasos Coronários/patologia , Vasos Coronários/fisiopatologia , Oclusão de Enxerto Vascular/metabolismo , Oclusão de Enxerto Vascular/patologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Artéria Torácica Interna/metabolismo , Artéria Torácica Interna/fisiopatologia , Neointima , Fatores de Risco , Veia Safena/metabolismo , Veia Safena/fisiopatologia , Fatores de Tempo , Falha de Tratamento , Grau de Desobstrução Vascular
12.
Ann Thorac Cardiovasc Surg ; 26(2): 88-94, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31611499

RESUMO

PURPOSE: To investigate the hemodynamics characteristics of the "no-touch" saphenous vein graft (SVG) conduits by nicardipine intraluminal administration in vivo experiment. METHODS: A total of 59 consecutive patients were enrolled and underwent a sequential SVG to three non-left anterior descending (LAD) targets with the average runoff ≤2 mm, 30 with "no-touch" harvest technique (group A) and 29 with conventional preparation (group B). The patients were subject to nicardipine intraluminal injection during off-pump coronary artery bypass grafting (CABG) procedure. The intraoperative flow was measured with the ultrasonic transit time flow meter (TTFM), and the graft patency testified by multi-detector computed tomography (MDCT) angiography, respectively. RESULTS: The baseline blood flow was higher in group A than that in group B (p <0.05). However, the increases in blood flow of SVG conduits in group A were lower than those in group B with 19.7 ± 5.9 vs. 35.4 ± 9.2 mL/min, 14.8 ± 5.6 vs. 23.1 ± 6.8 mL/min, 6.6 ± 2.1 vs. 11.2 ± 4.3 mL/min before the first, second, and third anastomose after nicardipine intraluminal administration, respectively (all p <0.01). CONCLUSIONS: No-touch SVGs were associated with higher baseline blood flow and less rises after nicardipine intraluminal administration during off-pump CABG procedure compared with conventional preparation. The no-touch SVGs seemed to be less spastic and well-tolerated on flow dilatation.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Doença da Artéria Coronariana/cirurgia , Nicardipino/administração & dosagem , Veia Safena/efeitos dos fármacos , Veia Safena/transplante , Grau de Desobstrução Vascular/efeitos dos fármacos , Vasodilatadores/administração & dosagem , Idoso , Pequim , Velocidade do Fluxo Sanguíneo , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Oclusão de Enxerto Vascular/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Nicardipino/efeitos adversos , Veia Safena/diagnóstico por imagem , Veia Safena/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Vasodilatadores/efeitos adversos
13.
Cardiovasc Res ; 116(2): 416-428, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30924866

RESUMO

AIMS: Therapies to prevent vein graft disease, a major problem in cardiovascular and lower extremity bypass surgeries, are currently lacking. Short-term preoperative protein restriction holds promise as an effective preconditioning method against surgical stress in rodent models, but whether it can improve vein graft patency after bypass surgery is undetermined. Here, we hypothesized that short-term protein restriction would limit vein graft disease via up-regulation of cystathionine γ-lyase and increased endogenous production of the cytoprotective gaseous signalling molecule hydrogen sulfide. METHODS AND RESULTS: Low-density lipoprotein receptor knockout mice were preconditioned for 1 week on a high-fat high-cholesterol (HFHC) diet with or without protein prior to left common carotid interposition vein graft surgery with caval veins from donor mice on corresponding diets. Both groups were returned to a complete HFHC diet post-operatively, and vein grafts analysed 4 or 28 days later. A novel global transgenic cystathionine γ-lyase overexpressing mouse model was also employed to study effects of genetic overexpression on graft patency. Protein restriction decreased vein graft intimal/media+adventitia area and thickness ratios and intimal smooth muscle cell infiltration 28 days post-operatively, and neutrophil transmigration 4 days post-operatively. Protein restriction increased cystathionine γ-lyase protein expression in aortic and caval vein endothelial cells (ECs) and frequency of lung EC producing hydrogen sulfide. The cystathionine γ-lyase inhibitor propargylglycine abrogated protein restriction-mediated protection from graft failure and the increase in hydrogen sulfide-producing ECs, while cystathionine γ-lyase transgenic mice displayed increased hydrogen sulfide production capacity and were protected from vein graft disease independent of diet. CONCLUSION: One week of protein restriction attenuates vein graft disease via increased cystathionine γ-lyase expression and hydrogen sulfide production, and decreased early inflammation. Dietary or pharmacological interventions to increase cystathionine γ-lyase or hydrogen sulfide may thus serve as new and practical strategies to improve vein graft durability.


Assuntos
Cistationina gama-Liase/biossíntese , Dieta com Restrição de Proteínas , Oclusão de Enxerto Vascular/prevenção & controle , Veia Cava Inferior/transplante , Animais , Artéria Carótida Primitiva/cirurgia , Colesterol na Dieta , Cistationina gama-Liase/genética , Dieta Hiperlipídica , Modelos Animais de Doenças , Indução Enzimática , Oclusão de Enxerto Vascular/enzimologia , Oclusão de Enxerto Vascular/patologia , Oclusão de Enxerto Vascular/fisiopatologia , Sulfeto de Hidrogênio/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neointima , Estado Nutricional , Receptores de LDL/deficiência , Receptores de LDL/genética , Fatores de Tempo , Grau de Desobstrução Vascular , Veia Cava Inferior/enzimologia , Veia Cava Inferior/patologia , Veia Cava Inferior/fisiopatologia
14.
Eur J Vasc Endovasc Surg ; 59(2): 288-294, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31883684

RESUMO

OBJECTIVE: Arteriovenous grafts (AVGs) typically lose patency within two years of creation due to venous neointimal hyperplasia, which is initiated by disturbed haemodynamics after AVG surgery. Haemodialysis needle flow can further disturb haemodynamics and thus impact AVG longevity. In this computational study it was assessed how dialysis flow and venous needle positioning impacts flow at the graft-vein anastomosis. Furthermore, it was studied how negative effects of dialysis needle flow could be mitigated. METHODS: Non-physiological wall shear stress and disturbed blood flow were assessed in an AVG model with and without dialysis needle flow. Needle distance to the venous anastomosis was set to 6.5, 10.0, or 13.5 cm, whereas dialysis needle flow was set to 200, 300 or 400 mL/min. Intraluminal needle tip depth was varied between superficial, central, or deep. The detrimental effects of dialysis needle flow were summarised by a haemodynamic score (HS), ranging from 0 (minimal) to 5 (severe). RESULTS: Dialysis needle flow resulted in increased disturbed flow and/or non-physiological wall shear stress in the venous peri-anastomotic region. Increasing cannulation distance from 6.5 to 13.5 cm reduced the HS by a factor 4.0, whereas a central rather than a deep or superficial needle tip depth reduced the HS by a maximum factor of 1.9. Lowering dialysis flow from 400 to 200 mL/min reduced the HS by a factor 7.4. CONCLUSION: Haemodialysis needle flow, cannulation location, and needle tip depth considerably increase the amount of disturbed flow and non-physiological wall shear stress in the venous anastomotic region of AVGs. Negative effects of haemodialysis needle flow could be minimised by more upstream cannulation, by lower dialysis flow and by ensuring a central needle tip depth. Since disturbed haemodynamics are associated with neointimal hyperplasia development, optimising dialysis flow and needle positioning during haemodialysis could play an important role in maintaining AVG patency.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Oclusão de Enxerto Vascular/prevenção & controle , Modelos Cardiovasculares , Neointima/patologia , Diálise Renal/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Implante de Prótese Vascular , Cânula/efeitos adversos , Simulação por Computador , Desenho Assistido por Computador , Oclusão de Enxerto Vascular/etiologia , Humanos , Hidrodinâmica , Hiperplasia/etiologia , Agulhas/efeitos adversos , Fluxo Sanguíneo Regional/fisiologia , Diálise Renal/instrumentação , Diálise Renal/métodos , Estresse Mecânico , Grau de Desobstrução Vascular/fisiologia
15.
Am J Cardiol ; 125(3): 320-327, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31780076

RESUMO

Limited data exist on the long-term efficacy of extended dual antiplatelet therapy (DAPT) after left main coronary artery (LMCA) bifurcation stenting. This study investigated the long-term clinical outcomes associated with long-term DAPT after LMCA bifurcation stenting. Using data from the multicenter KOMATE and COBIS registries, we analyzed 1,142 patients who received a drug-eluting stent for a LMCA bifurcation lesion and who experienced no adverse events for 12 months after the index procedure. Patients were divided into 2 groups: DAPT >12 months (n = 769) and DAPT ≤12 months (n = 373). The primary end point was major adverse cardiovascular events (MACEs), as a composite of cardiac death, myocardial infarction, stroke, and stent thrombosis, over 5 years of follow-up. We further performed propensity score adjustment for clinical outcomes. DAPT >12 months afforded a lower MACE rate than DAPT ≤12 months (2.3% vs 5.4%, adjusted hazard ratio [HR] 0.37; 95% confidence interval [CI] 0.19 to 0.71; p = 0.003). The use of DAPT for >12 months was an independent predictor of a reduced likelihood of MACEs (HR 0.34; 95% CI 0.17 to 0.67; p = 0.002). A DAPT score ≥2, chronic kidney disease, and age >75 years were significant independent predictors of MACEs. In subgroup analysis, the use of DAPT for >12 months consistently resulted in better clinical outcomes across all subgroups, especially among patients with ACS, compared with the use of DAPT for ≤12 months. In conclusion, an extended duration of DAPT reduces MACE rates after LMCA bifurcation stenting.


Assuntos
Doença da Artéria Coronariana/cirurgia , Vasos Coronários/cirurgia , Stents Farmacológicos , Terapia Antiplaquetária Dupla/métodos , Oclusão de Enxerto Vascular/prevenção & controle , Intervenção Coronária Percutânea/métodos , Aspirina/uso terapêutico , Clopidogrel/uso terapêutico , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Feminino , Seguimentos , Oclusão de Enxerto Vascular/diagnóstico , Oclusão de Enxerto Vascular/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação de Plaquetas/uso terapêutico , Prognóstico , Sistema de Registros , República da Coreia/epidemiologia , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo
16.
Cardiovasc Ther ; 2019: 1582183, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772605

RESUMO

Background: Decreased graft patency after off-pump coronary artery bypass grafting (OPCAB) leads to substantial increases in cardiac events. However, there is paucity of data on efficacy and safety of perioperative statin therapy for OPCAB populations. Methods: 582 patients undergoing OPCAB in a single-institution database (October 1, 2009-September 30, 2012) were stratified by perioperative continuation of statin therapy (CS group, n=398) or not (DS group, n=184). Inverse probability weighted propensity adjustment was used to account for treatment assignment bias, resulting in a well-matched cohort. Primary outcomes were graft patency at an average of five days after operation and in-hospital mortality. Secondary outcomes included intraoperative blood loss, liver, and renal functions. Results: No in-hospital death occurred in this study. Early graft patency rates after OPCAB were 98.4% (1255 of 1275 grafts) in the CS group and 98.0% (583 of 595 grafts, P=0.486) in the DS group. Secondary outcomes showed a reduction in blood loss during operation (438.53 mL versus 480.47 mL, P=0.01). Continuation of statin therapy is associated with alanine transaminase (ALT) elevation (49.67 U/L versus 34.52 U/L, P<0.001), as well as aspartate transaminase (33.54 U/L versus 28.10 U/L, P<0.001). Abnormal ALT elevation was observed in 8.9% of the CS group and 3.1% in DS (odds ratio 3.06, 95% confidence interval, 1.77 to 5.29, P<0.001). There was no significant difference in estimated glomerular filtration rate (76.28 mL/min/1.73m2 versus 76.13 mL/min/1.73m2, P=0.90). Subgroup analyses suggested that graft occlusion was less common in CS than in DS group among smoking patients (odds ratio 0.41, 95% confidence interval, 0.20 to 0.86, P=0.026). Conclusions: Perioperative continuation of statin therapy did not improve early graft patency in OPCAB patients. A lower risk of graft occlusion was observed among smoking patients. Continuous statin use correlated with liver function elevation (Clinical Trials.gov number, NCT01268917).


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Doença da Artéria Coronariana/cirurgia , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Assistência Perioperatória , Grau de Desobstrução Vascular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Bases de Dados Factuais , Esquema de Medicação , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Oclusão de Enxerto Vascular/prevenção & controle , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fumar/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
17.
Adv Mater ; 31(41): e1904476, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31454108

RESUMO

Inserting a graft into vessels with different diameters frequently causes severe damage to the host vessels. Poor flow patency is an unresolved issue in grafts, particularly those with diameters less than 6 mm, because of vessel occlusion caused by disturbed blood flow following fast clotting. Herein, successful patency in the deployment of an ≈2 mm diameter graft into a porcine vessel is reported. A new library of property-tunable shape-memory polymers that prevent vessel damage by expanding the graft diameter circumferentially upon implantation is presented. The polymers undergo seven consecutive cycles of strain energy-preserved shape programming. Moreover, the new graft tube, which features a diffuser shape, minimizes disturbed flow formation and prevents thrombosis because its surface is coated with nitric-oxide-releasing peptides. Improved patency in a porcine vessel for 18 d is demonstrated while occlusive vascular remodeling occurs. These insights will help advance vascular graft design.


Assuntos
Oclusão de Enxerto Vascular/prevenção & controle , Fenômenos Mecânicos , Polímeros/farmacologia , Animais , Polímeros/química , Estresse Mecânico , Suínos
18.
ACS Appl Mater Interfaces ; 11(31): 28307-28316, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31356048

RESUMO

Cardiovascular and cerebrovascular ischemic diseases seriously affect human health. Endovascular stent placement is an effective treatment but always leads to in-stent restenosis (ISR). Gene-eluting stent, which combines gene therapy with stent implantation, is a potential method to prevent ISR. In this study, an efficient gene-eluting stent was designed on the basis of one new nucleic acid delivery system to decrease the possibility of ISR. The reduction-responsive branched nucleic acid vector (SKP) with low cytotoxicity was first synthesized via ring-opening reaction. The impressive in vitro transfection performances of SKP were proved using luciferase reporter, enhanced green fluorescent protein plasmid, and vascular endothelial growth factor plasmid (pVEGF). Subsequently, SKP/pVEGF complexes were coated on the surfaces of pretreated clinical stents to construct gene-eluting stents (S-SKP/pVEGF). Antirestenosis performance of S-SKP/pVEGF was evaluated via implanting stents into rabbit aortas. S-SKP/pVEGF could lead to the localized upregulation of VEGF proteins, improve the progress of re-endothelialization, and inhibit the development of ISR in vivo. Such efficient pVEGF-eluting stent with responsive nucleic acid delivery systems is very promising to prevent in-stent restenosis of cerebrovascular diseases.


Assuntos
Técnicas de Transferência de Genes , Oclusão de Enxerto Vascular/prevenção & controle , Stents , Fator A de Crescimento do Endotélio Vascular , Animais , Oclusão de Enxerto Vascular/genética , Oclusão de Enxerto Vascular/metabolismo , Oclusão de Enxerto Vascular/patologia , Coelhos , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/genética
19.
Int J Artif Organs ; 42(12): 675-683, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31303134

RESUMO

OBJECTIVE: To clarify the reasons and beneficial effects and duration of arteriovenous fistula patency after radiological interventions in arteriovenous fistula. The patients investigated were referred due to arteriovenous fistula access flow problems. MATERIAL AND METHODS: In 174 patients, 522 radiological investigations and endovascular treatments such as percutaneous transluminal angioplasty were analyzed, retrospectively. All investigations were performed due to clinical suspicion of impaired arteriovenous fistula function. RESULTS: Arterial stenosis was significantly more frequent among patients with diabetic nephropathy (p < 0.001) and interstitial nephritis (p < 0.001). According to the venous stenosis, the diagnosis did not affect the frequency (p = 0.22) or the degree (p = 0.39) of stenosis. The degree of stenosis prior to percutaneous transluminal angioplasty correlated significantly with the degree of remaining stenosis after intervention (p < 0.001). Of the 174 patients, 123 (71%) performed a total of 318 investigations including percutaneous transluminal angioplasty. Repeated percutaneous transluminal angioplasty was performed significantly more often in patients with diabetic nephropathy. The median times to the first percutaneous transluminal angioplasty and to the subsequent percutaneous transluminal angioplasties were 9.5 and 5 months, respectively. Arteriovenous fistula in patients with diabetic nephropathy performed similar to most other diagnoses, although performing more percutaneous transluminal angioplasty/patient than most other diagnoses. CONCLUSION: Many patients could maintain long-term patency of arteriovenous fistula, including those with diabetic nephropathy, with repeated interventions; this motivates a closer follow-up for these patients. Clinically significant stenosis should be dilated as meticulously and as soon as possible. Occlusions of the arteriovenous fistula in most instances can be successfully thrombolyzed or dilated upon early diagnosis.


Assuntos
Angiografia/métodos , Angioplastia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Oclusão de Enxerto Vascular , Flebografia/métodos , Diálise Renal , Idoso , Angiografia/estatística & dados numéricos , Angioplastia/efeitos adversos , Angioplastia/métodos , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/prevenção & controle , Oclusão de Enxerto Vascular/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Flebografia/estatística & dados numéricos , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Suécia/epidemiologia , Resultado do Tratamento , Grau de Desobstrução Vascular
20.
Cardiol Young ; 29(7): 877-884, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31208476

RESUMO

OBJECTIVE: To define optimal thromboprophylaxis strategy after stent implantation in superior or total cavopulmonary connections. BACKGROUND: Stent thrombosis is a rare complication of intravascular stenting, with a perceived higher risk in single-ventricle patients. METHODS: All patients who underwent stent implantation within superior or total cavopulmonary connections (caval vein, innominate vein, Fontan, or branch pulmonary arteries) were included. Cohort was divided into aspirin therapy alone versus advanced anticoagulation, including warfarin, enoxaparin, heparin, or clopidogrel. Primary endpoint was in-stent or downstream thrombus, and secondary endpoints included bleeding complications. RESULTS: A total of 58 patients with single-ventricle circulation underwent 72 stent implantations. Of them 14 stents (19%) were implanted post-superior cavopulmonary connection and 58 (81%) post-total cavopulmonary connection. Indications for stenting included vessel/conduit stenosis (67%), external compression (18%), and thrombotic occlusion (15%). Advanced anticoagulation was prescribed for 32 (44%) patients and aspirin for 40 (56%) patients. Median follow up was 1.1 (25th-75th percentile, 0.5-2.6) years. Echocardiograms were available in 71 patients (99%), and advanced imaging in 44 patients (61%). Thrombosis was present in two patients on advanced anticoagulation (6.3%) and none noted in patients on aspirin (p = 0.187). Both patients with in-stent thrombus underwent initial stenting due to occlusive left pulmonary artery thrombus acutely post-superior cavopulmonary connection. There were seven (22%) significant bleeding complications for advanced anticoagulation and none for aspirin (p < 0.001). CONCLUSIONS: Antithrombotic strategy does not appear to affect rates of in-stent thrombus in single-ventricle circulations. Aspirin alone may be sufficient for most patients undergoing stent implantation, while pre-existing thrombus may warrant advanced anticoagulation.


Assuntos
Anticoagulantes/uso terapêutico , Fibrinolíticos/uso terapêutico , Técnica de Fontan/efeitos adversos , Oclusão de Enxerto Vascular/prevenção & controle , Stents/efeitos adversos , Coração Univentricular/cirurgia , Aspirina/uso terapêutico , Criança , Pré-Escolar , Feminino , Oclusão de Enxerto Vascular/etiologia , Humanos , Lactente , Masculino , Estudos Retrospectivos
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