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1.
J Artif Organs ; 19(4): 403-407, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27086125

RESUMO

A 70-year-old woman underwent an axillobifemoral artery bypass using a bifurcated ring-supported Dacron graft in 2004 and then noticed a pulsatile mass in the left flank 10 years later. A Fogarty thrombectomy was performed for acute graft occlusion. Eight months later, computed tomography revealed pseudoaneurysm formation in the graft body and surgical graft interposition was performed. The operative findings showed a transverse rupture of the graft just above the bifurcation. Histological findings revealed graft deterioration with filaments broken off from the graft. Although the cause of pseudoaneurysm formation was not apparent, the combination of graft deterioration and additional damage from the Fogarty thrombectomy was highly suspicious.


Assuntos
Falso Aneurisma/etiologia , Derivação Axilofemoral/instrumentação , Prótese Vascular/efeitos adversos , Complicações Pós-Operatórias/etiologia , Trombectomia , Idoso , Falso Aneurisma/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Feminino , Artéria Femoral/cirurgia , Oclusão de Enxerto Vascular/cirurgia , Humanos , Polietilenotereftalatos
2.
J Cardiol Cases ; 30(1): 20-23, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39007041

RESUMO

An 83-year-old woman with claudication in the right lower extremity was referred to our hospital. Since angiography showed severe stenosis with a severely calcified lesion extending from the ostial to proximal part of the right superficial femoral artery (SFA), endovascular therapy (EVT) with the Jetstream™ atherectomy system (Boston Scientific, Marlborough, MA, USA) and paclitaxel-coated balloon (PCB) was performed. Atherectomy was performed using the Jetstream™ atherectomy catheter SC 1.85, followed by an additional atherectomy using the Jetstream™ atherectomy catheter XC 2.1/3.0. Subsequently, angiography and intravascular ultrasound (IVUS) images showed the enlargement of lumen area due to the reduction of calcified plaque, but even some of the healthy media on the side free of calcified plaque had been removed. Next, a PCB dilation was performed, and the final angiography showed adequate dilation. However, the symptoms recurred 9 months after EVT. Angiography revealed an enlarged vessel suggestive of pseudoaneurysm at the ostial part of the right SFA and severe stenosis distal to the enlarged vessel. IVUS images showed a pseudoaneurysm and severe stenosis due to calcified nodules distal to the pseudoaneurysm. This case suggests that pseudoaneurysm is a potential complication of EVT with the Jetstream™ atherectomy system and PCB for SFA lesions. Learning objective: The Jetstream™ atherectomy system (Boston Scientific, Marlborough, MA, USA) has developed to improve outcomes for femoropopliteal artery lesions with severely calcified lesions in lower extremity arterial disease by removing calcified plaque and improving vascular compliance. Several clinical reports demonstrated durable patency rates and low complication rates after endovascular therapy using the atherectomy device. However, pseudoaneurysm is a potential complication of endovascular therapy with the Jetstream™ atherectomy system.

3.
Ann Vasc Surg ; 27(6): 802.e5-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23535526

RESUMO

A 39-year-old man with a thoracic aortic aneurysm and pseudocoarctation underwent graft replacement of the distal arch. The left subclavian artery, which rose just after the aneurysm, was also reconstructed at surgery. The aneurysmal wall was extremely thin, and the adventitia and a small amount of medial tissue were found on histologic examination. Thus, surgical treatment was recommended due to risk of rupture. Furthermore, because aneurysms involved the cervical branch, separate reconstruction was also performed. Endovascular intervention is not appropriate for this group of patients because of the complex kinking of the aorta and the extremely thin aneurysmal wall.


Assuntos
Aneurisma da Aorta Torácica/complicações , Coartação Aórtica/complicações , Artéria Subclávia , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Aneurisma/complicações , Aneurisma/diagnóstico por imagem , Aneurisma/cirurgia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Coartação Aórtica/diagnóstico por imagem , Coartação Aórtica/cirurgia , Humanos , Imageamento Tridimensional , Masculino , Tomografia Computadorizada por Raios X
4.
J Cardiol ; 82(4): 261-267, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37276990

RESUMO

BACKGROUND: There have been few reports on the mid- to long-term safety and efficacy validation of the INSPIRIS RESILIA aortic bioprosthesis (Edwards Lifesciences LLC, Irvine, CA, USA) in Japan. Herein, we report the mid-term results of surgical aortic valve replacement (AVR) for aortic stenosis using INSPIRIS and evaluate the hemodynamics compared to the CEP Magna series from the multicenter AVR registry (the ACTIVIST registry). METHODS: Of the 1967 patients who underwent surgical or transcatheter AVR from the ACTIVIST registry, 66 patients who underwent isolated surgical AVR with INSPIRIS by December 2020 were included in this study, and the early and mid-term results were evaluated. Hemodynamics were evaluated by comparing 272 patients undergoing isolated surgical AVR with the Magna group using propensity score matching. RESULTS: The mean age was 74.0 ±â€¯7.8 years, and 48.5 % were women. In-hospital mortality was 1.5 %, and the survival rates at 1- and 2-years were 95.2 % and 95.2 %, respectively. After propensity score matching, echocardiographic findings at discharge demonstrated that peak velocity and mean pressure gradient in the INSPIRIS group were comparable, while the effective orifice area in the INSPIRIS group was significantly larger than those in the Magna group (p = 0.048). A patient-prosthesis mismatch at discharge was significantly lower in the INSPIRIS group (11.8 %) than in the Magna group (36.4 %) (p = 0.004). CONCLUSIONS: Surgical AVR with INSPIRIS was performed safely and the mid-term results were satisfactory. The hemodynamics of INSPIRIS were comparable to those of Magna.


Assuntos
Estenose da Valva Aórtica , Bioprótese , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Humanos , Feminino , Idoso , Idoso de 80 Anos ou mais , Masculino , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Resultado do Tratamento , Estenose da Valva Aórtica/cirurgia , Sistema de Registros , Hemodinâmica , Desenho de Prótese , Estudos Retrospectivos
5.
Osaka City Med J ; 58(1): 39-44, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23094513

RESUMO

Pericardial effusion and cardiac tamponade are often refractory and difficult to manage. The transthoracic pericardial fenestration which create a window is the conventional procedure for releasing pericardial effusion to the thoracic cavity. We experienced two cases of pericardial fenestration. The first case was a patient with hypertrophic cardiomyopathy with pericardial effusion. She had a thoracic compression fracture, which indicated pericardial fenestration before an orthopedic surgery. The second case was a patient with recurrent cardiac tamponade caused by postpericardiotomy syndrome after off-pump coronary artery bypass grafting. In both cases, the patients underwent left anterior thoracotomy of about 10 cm at the level of the 5th intercostal space. The pericardium was incised within a radius of about 20 mm; furthermore, the fenestrated window was opened to the left thoracic cavity. In this paper, we present our experience of pericardial fenestration and discuss a review of the literature.


Assuntos
Derrame Pericárdico/cirurgia , Técnicas de Janela Pericárdica , Idoso , Feminino , Humanos , Masculino
6.
Int J Angiol ; 31(1): 56-60, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35221854

RESUMO

Aortic arch pathology in a high-risk patient in whom the resternotomy approach is unfeasible due to treated mediastinitis after ascending aortic replacement presents a unique challenge for hybrid arch repair (HAR) because of the need for supra-aortic debranching from unusual inflow sites other than the ascending aorta. This report describes a "reversed sequence" extra-anatomical supra-aortic debranching procedure as a salvage technique performed to enable HAR. An 83-year-old woman with a history of ascending aortic replacement for type A aortic dissection, mediastinitis complicated by sternal osteomyelitis, and a chest wall reconstructed with a rectus abdominis myocutaneous flap presented with chest pain because of a contained dissecting arch aneurysm rupture. The patient underwent supra-aortic debranching from the bilateral common femoral arteries and thoracic endovascular aortic repair to the ascending aorta under cerebral near-infrared spectroscopy (NIRS) monitoring. Completion imaging by angiography demonstrated successful exclusion of the ruptured aneurysm. The regional cerebral oxygen saturation level, monitored by NIRS, did not change markedly during surgery. The patient was neurologically intact with adequate cerebral blood flow assessed postoperatively by 123 I-IMP single photon emission computed tomography. Total debranching of the supra-aortic vessels from the common femoral artery for inflow is feasible and provides adequate cerebral perfusion. This procedure may offer an alternative treatment option in patients with complex conditions involving aortic arch pathology.

7.
Eur Heart J Case Rep ; 5(2): ytab048, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33738421

RESUMO

BACKGROUND: Subepicardial aneurysm (SEA) is an uncommon but potentially fatal complication of acute myocardial infarction (MI) associated with an increased risk of free wall rupture (FWR) leading to sudden death. We describe a rare case of a silent myocardial infarction complicated by SEA and subsequent FWR, resulting in cardiac tamponade. CASE SUMMARY: A 68-year-old man with no previous chest symptoms presented with syncope. Cardiac computed tomography incidentally revealed a small aneurysmal cavity at the inferolateral wall of the left ventricle, which was overlooked on initial transthoracic echocardiography. Coronary angiography demonstrated a narrowed first obtuse marginal branch with coronary slow flow, suggesting that spontaneous recanalization of the occluded obtuse marginal branch induced SEA and subsequent FWR. The patient underwent an emergency left ventricular aneurysm repair. The post-operative course was uneventful, and the patient was discharged from the hospital on post-operative day 20. DISCUSSION: This case emphasizes the importance of prompt detection and surgical intervention for SEA. Subepicardial aneurysm should be suspected in patients with pericardial effusion and suspected MI. Cardiac computed tomography is not only useful in the detection of such cases but also facilitates the development of a successful surgical strategy.

8.
JACC Case Rep ; 3(15): 1705-1710, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34766023

RESUMO

We report the unusual case of a 68-year-old man with coral reef aorta complicated with severe calcified valvular heart disease who has been undergoing dialysis for 21 years. This report highlights the etiology and the unusual manifestations of coral reef aorta in a long-term dialysis patient. (Level of Difficulty: Intermediate.).

9.
JACC Case Rep ; 2(15): 2363-2367, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34317172

RESUMO

We describe the case of a young woman with Takayasu arteritis with severe stenosis in the main trunk of the left coronary artery. After administration of prednisolone and tocilizumab to control disease activity, coronary artery bypass grafting was performed. Here, we report the successful perioperative management of this cardiac surgery. (Level of Difficulty: Advanced.).

10.
Int J Angiol ; 28(1): 39-43, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30880892

RESUMO

Graft infections are a challenging complication in lower extremity bypass surgery with poor outcome, even when treated with graft removal (Gr-R) as a gold standard therapy. The efficacy of negative pressure wound therapy (NPWT) for graft infections has been reported recently, but it is still controversial. The purpose of this study was to assess the efficacy of NPWT and Gr-R for treating graft infections. Twelve consecutive patients with graft infections from 2008 to 2014, treated with Gr-R or NPWT, were enrolled. Those procedures were assessed in complete wound healing, reinfection, amputation, and mortality rate. Five grafts were treated with Gr-R, and seven grafts with NPWT. The initial indications for bypass surgery were claudication, in five grafts treated with Gr-R and three grafts treated with NPWT, and critical limb ischemia in four grafts treated with NPWT. The median time until healing in Gr-R and NPWT was 12 and 59 days, with complete healing seen in 100 and 85.7%, respectively. The major amputation rate was 20 and 14.3%, and reinfection rate was 20 and 14.3%, respectively. There was no perioperative mortality. Gr-R did not show devastating outcome when applied for grafts without limb-threatening ischemia. NPWT showed a low level of invasiveness with excellent results, except for anastomosis site infections. To achieve optimal results, a tailored treatment strategy should be considered.

11.
Ann Thorac Surg ; 108(2): 481-490, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30914284

RESUMO

BACKGROUND: A successful endovascular treatment for acute type A dissection has been recently reported. However, there has been no consensus regarding the appropriate stent graft size based on the estimated predissected aortic diameter for this pathology. METHODS: We developed new equations for estimating the predissected ascending aorta and aortic arch by investigating computed tomography images that had been scanned less than 3 years before dissection. From 684 patients with type A AAD, 28 were matched for the study. We measured the predissected whole circumference length (pre-wCL), postdissected whole circumference length (post-wCL), postdissected true lumen circumference length (post-tCL), postdissected major diameter (post-Dma), and postdissected minor diameter (post-Dmi) of the acutely dissected aorta. This was followed by the calculation of (post-tCL + post-wCL)/2 and (post-Dma + post-Dmi)/2. Six equations (linear function) and modified equations were derived from each of the abovementioned parameters. RESULTS: Four equations (post-wCL, post-Dma, [post-tCL + post-wCL]/2, and [post-Dma + post-Dmi]/2) had nearly the same bias and accuracy (<9.42 mm). For clinical use, we also developed one modified equation using the post-wCL (y = 0.9x) among four parameters because of its simplicity and decreased the possibility of measurement error. The biases of circumference length and accuracy were 5.5 ± 4.9 mm and 84.6%, respectively, and they improved to 4.4 ± 3.3 mm and 93.4% in cases with a ratio of post-tCL/post-wCL of 0.66 or more. CONCLUSIONS: Our newly developed equation can be used to calculate the predissected ascending aortic diameter and aortic arch diameter in cases of acute type A dissection.


Assuntos
Algoritmos , Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico , Dissecção Aórtica/diagnóstico , Procedimentos Endovasculares/métodos , Stents , Doença Aguda , Idoso , Dissecção Aórtica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Angiografia por Tomografia Computadorizada , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
13.
Surg Case Rep ; 2(1): 85, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27576460

RESUMO

BACKGROUND: Ventricular septal rupture (VSR) is a life-threatening complication following acute transmural myocardial infarction. Posteriorly located ruptures are one of the main predictors of poor prognoses because of the surgical difficulties associated with this location. CASE PRESENTATION: A 72-year-old man with a posterior VSR underwent surgical repair via the right atrial approach. The patient's postoperative course was uneventful, and echocardiography showed no residual shunt flow. He was discharged on postoperative day 37. CONCLUSION: By temporally detaching the tricuspid valve leaflet, this approach provides a better view and handling space within the posterior ventricular septum than the trans-ventricular approach. Additionally, avoiding a ventricular incision can better preserve postoperative ventricular function.

14.
Asian Cardiovasc Thorac Ann ; 13(1): 42-6, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15793050

RESUMO

To evaluate the invasiveness of a minimal access approach for simple congenital heart defects, and determine whether it can be regarded as a standard operation, 83 patients with an atrial septal defect and 73 with a ventricular septal defect underwent repair through a minimal skin incision and lower partial median sternotomy. There were no operative deaths, severe intraoperative complications, or conversion to full sternotomy. The clinical course of 106 patients was compared with that of 21 treated using a full sternotomy by the same surgeon; there were no significant differences, except in the operative time for ASD patients. The clinical courses of 2 minimal access subgroups (50 patients operated on by residents and 106 treated by the staff surgeon were compared; operative time, bypass time, ventricular fibrillation time (ASD repair), and cardiac arrest time (VSD repair) were significantly shorter in those operated on by the staff surgeon, but there was no difference in clinical course. The minimal access approach produced good cosmetic results, its invasiveness was similar to that of a full sternotomy, and it may be considered a standard operation for pediatric patients with septal defects.


Assuntos
Comunicação Interatrial/cirurgia , Comunicação Interventricular/cirurgia , Esterno/cirurgia , Toracotomia/métodos , Adolescente , Criança , Pré-Escolar , Competência Clínica , Feminino , Humanos , Lactente , Tempo de Internação , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Estudos Retrospectivos , Resultado do Tratamento
17.
Tissue Eng Part A ; 17(1-2): 115-25, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20677907

RESUMO

Myoblast transplantation therapy for chronic heart failure (HF) is impaired by early donor cell death and reduced graft viability. Although epicardial implantation of cell sheets can prevent the initial loss of transplanted cells, limited vascularization subjects the sheets to apoptotic stress. We studied the efficacy of antiapoptotic bcl2 in myoblast sheet therapy for rat chronic HF. Myocardial infarction was induced by left anterior descending coronary artery ligation and HF was allowed to develop for 4 weeks. Thereafter, wild type (L6-WT; n=16) or Bcl-2-expressing (L6-Bcl2; n=19) myoblast sheets were transplanted epicardially. Control rats (n=21) underwent left anterior descending coronary artery ligation and re-thoracotomy. Five rats were sham-operated in both surgeries. Four weeks after transplantation, only the L6-Bcl2 rats showed improved left ventricular ejection fraction. Their vascular density in the damaged myocardium was greater, and they had more proliferating cells. The L6-Bcl2 group had an increased amount of myocytes in the infarct area. Soluble factors from L6-Bcl2 sheets induced a 2.9-fold increase in endothelial cell proliferation, and enhanced endothelial wound healing as compared to the L6-WT sheets. These effects were inhibited by SU5416 and were thus dependent on Flt1/Flk1 signaling. In conclusion, bcl2 improves efficacy of myoblast sheet transplantation and promotes proangiogenic paracrine signaling.


Assuntos
Insuficiência Cardíaca/terapia , Mioblastos/citologia , Proteínas Proto-Oncogênicas c-bcl-2/farmacologia , Animais , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ecocardiografia , Células Endoteliais/citologia , Humanos , Ratos , Ratos Wistar , Cordão Umbilical/citologia , Cicatrização/fisiologia
18.
PLoS One ; 6(4): e19161, 2011 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-21541335

RESUMO

After severe myocardial infarction (MI), heart failure results from ischemia, fibrosis, and remodeling. A promising therapy to enhance cardiac function and induce therapeutic angiogenesis via a paracrine mechanism in MI is myoblast sheet transplantation. We hypothesized that in a rat model of MI-induced chronic heart failure, this therapy could be further improved by overexpression of the antiapoptotic, antifibrotic, and proangiogenic hepatocyte growth factor (HGF) in the myoblast sheets. We studied the ability of wild type (L6-WT) and human HGF-expressing (L6-HGF) L6 myoblast sheet-derived paracrine factors to stimulate cardiomyocyte, endothelial cell, or smooth muscle cell migration in culture. Further, we studied the autocrine effect of hHGF-expression on myoblast gene expression profiles by use of microarray analysis. We induced MI in Wistar rats by left anterior descending coronary artery (LAD) ligation and allowed heart failure to develop for 4 weeks. Thereafter, we administered L6-WT (n = 15) or L6-HGF (n = 16) myoblast sheet therapy. Control rats (n = 13) underwent LAD ligation and rethoracotomy without therapy, and five rats underwent a sham operation in both surgeries. We evaluated cardiac function with echocardiography at 2 and 4 weeks after therapy, and analyzed cardiac angiogenesis and left ventricular architecture from histological sections at 4 weeks. Paracrine mediators from L6-HGF myoblast sheets effectively induced migration of cardiac endothelial and smooth muscle cells but not cardiomyocytes. Microarray data revealed that hHGF-expression modulated myoblast gene expression. In vivo, L6-HGF sheet therapy effectively stimulated angiogenesis in the infarcted and non-infarcted areas. Both L6-WT and L6-HGF therapies enhanced cardiac function and inhibited remodeling in a similar fashion. In conclusion, L6-HGF therapy effectively induced angiogenesis in the chronically failing heart. Cardiac function, however, was not further enhanced by hHGF expression.


Assuntos
Insuficiência Cardíaca/terapia , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/uso terapêutico , Mioblastos/metabolismo , Neovascularização Fisiológica , Animais , Apoptose , Bioensaio , Linhagem Celular , Doença Crônica , Fibrose , Regulação da Expressão Gênica , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Testes de Função Cardíaca , Humanos , Mioblastos/patologia , Ratos , Ratos Wistar , Transfecção , Ultrassonografia , Vasodilatação/fisiologia
19.
Cell Transplant ; 19(5): 573-88, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20089207

RESUMO

Myoblast sheet transplantation is a promising novel treatment modality for heart failure after an ischemic insult. However, low supply of blood and nutrients may compromise sheet survival. The aim of this study was to investigate the effect of mitochondria-protective Bcl-2-modified myoblasts in cell sheet transplantation therapy. In the Bcl-2-expressing rat L6 myoblast sheets (L6-Bcl2), increased expression of myocyte markers and angiogenic mediators was evident compared to wild-type (L6-WT) sheets. The L6-Bcl2 sheets demonstrated significant resistance to apoptotic stimuli, and their differentiation capacity in vitro was increased. We evaluated the therapeutic effect of Bcl-2-modified myoblast sheets in a rat model of acute myocardial infarction (AMI). Sixty-four Wistar rats were divided into four groups. One group underwent AMI (n = 22), another AMI and L6-WT sheet transplantation (n = 17), and a third AMI and L6-Bcl2 sheet transplantation (n = 20). Five rats underwent a sham operation. Echocardiography was performed after 3, 10, and 28 days. Samples for histological analysis were collected at the end of the study. After AMI, the Bcl-2-expressing sheets survived longer on the infarcted myocardium, and significantly improved cardiac function. L6-Bcl2 sheet transplantation reduced myocardial fibrosis and increased vascular density in infarct and border areas. Moreover, the number of c-kit-positive and proliferating cells in the myocardium was increased in the L6-Bcl2 group. In conclusion, Bcl-2 prolongs survival of myoblast sheets, increases production of proangiogenic paracrine mediators, and enhances the therapeutic efficacy of cell sheet transplantation.


Assuntos
Mioblastos/transplante , Infarto do Miocárdio/terapia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Animais , Apoptose/fisiologia , Linhagem Celular Tumoral , Células Cultivadas , Perfilação da Expressão Gênica , Humanos , Masculino , Mioblastos/metabolismo , Mioblastos/fisiologia , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ratos , Ratos Wistar , Transfecção , Função Ventricular Esquerda/fisiologia
20.
Ann Thorac Surg ; 88(4): 1269-76, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19766820

RESUMO

BACKGROUND: We have developed a tissue-engineered patch for cardiovascular repair. Tissue-engineered patches facilitated site-specific in situ recellularization and required no pretreatment with cell seeding. This study evaluated the patches implanted into canine pulmonary arteries. METHODS: Tissue-engineered patches are biodegradable sheets woven with double-layer fibers. The fiber is composed of polyglycolic acid and poly-L-lactic acid, and compounding collagen microsponges. The patches (20- x 25-mm) were implanted into the canine pulmonary arterial trunks. At 1, 2, and 6 months after implantation (n = 4), they were explanted and characterized by histologic and biochemical analyses. Commercially available patches served as the control. No anticoagulant therapy was administered postoperatively. RESULTS: No aneurysm or thrombus was present within the patch area in all groups. The remodeled tissue predominantly consisted of elastic and collagen fibers, and the endoluminal surface was covered with a monolayer of endothelial cells and multilayers of smooth muscle cells beneath the endothelial layer. The elastic and collagen fibers and smooth muscle cells kept increasing with a maximum at 6 months, while a monolayer of endothelial cells was preserved. The expression levels of messenger RNA of several growth factors in the tissue-engineered patches were higher than those of native tissue at 1 and 2 months and decreased to normal level at 6 months. No regenerated tissue was found on the endoluminal surface in the control group. CONCLUSIONS: The novel tissue-engineered patches showed in situ repopulation of host cells without prior ex vivo cell seeding. This is promising material for repair of the cardiovascular system.


Assuntos
Implantes Absorvíveis , Prótese Vascular/tendências , Músculo Liso Vascular/ultraestrutura , Artéria Pulmonar/cirurgia , Engenharia Tecidual/tendências , Animais , Modelos Animais de Doenças , Cães , Seguimentos , Imuno-Histoquímica , Microscopia Eletrônica de Varredura , Desenho de Prótese , Artéria Pulmonar/ultraestrutura , Resistência à Tração
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