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Um novo substituto vascular: arterioplastia femoral em c?es com remendo de membrana de biopolímero de cana-de-a?úcar - avalia??o hemodinamica e histopatológica
Marques, Silvio Romero de Barros;Lins, Esdras Marques;Aguiar, José Lamartine de Andrade;Albuquerque, Maria Claudia Sodré;Rossiter, Renata de Oliveira;Montenegro, Luciano Tavares;Vieira, Roberto José;
Jornal Vascular Brasileiro , 2007, DOI: 10.1590/S1677-54492007000400003
Abstract: background: achievement of an ideal arterial substitute to be used in the reconstruction of small- and medium-caliber arteries is still the main objective of most scientific research studies developed in the area of vascular substitutes. sugarcane biopolymer membrane could be extremely useful to perform vascular reconstruction in arteries with diameter smaller than 4 mm, allowing treatment of diseases that affect millions of people in brazil and worldwide. objective: to evaluate the hemodynamic and histopathologic behavior of sugarcane biopolymer membrane when used as a patch in femoral artery angioplasty in dogs. method: eight adult mongrel dogs, under general anesthesia, underwent percutaneous doppler velocimetry of the left and right femoral arteries for preoperative control at the health sciences center experimental research laboratory of universidade federal de pernambuco. after being disinfected, the dogs underwent femoral artery patch angioplasty using a sugarcane membrane biopolymer patch on the left side and an expanded ptfe (e-ptfe) patch on the right side. the dogs underwent daily clinical evaluation for the first week and weekly thereafter. clinical evaluation consisted of an examination of femoral artery pulses, gait assessment and verification as to whether there was any pulsatile tumor, bruising, hemorrhage or surgical wound infection. one hundred and eighty days after the angioplasties, percutaneous doppler velocimetry of the femoral arteries was performed under general anesthesia. next, the dogs underwent dissection of the femoral arteries, measurement of the arterial diameter and perioperative doppler velocimetry proximally and distally to the artery angioplasty. laparotomy was then performed to expose the abdominal aorta for angiographic access. the femoral artery segments with patches were harvested for histopathologic analysis, and the animals were sacrificed under a toxic dosage of anesthetic. results: at 180 days, no cases of surgical wound in
The effect of femoral and popliteal percutaneous transluminal balloon angioplasty on patients' quality of life
Slovacek, Ladislav;Slovackova, Birgita;Chovanec, Vendelin;
Sao Paulo Medical Journal , 2007, DOI: 10.1590/S1516-31802007000400012
Abstract: context and objective: peripheral arterial occlusive disease (paod) is a prevalent atherosclerotic disorder characterized by limb pain on exertion, limb loss and a high mortality rate. because of its chronic nature, it often has a negative impact on patients' quality of life (qol). this study aimed to assess qol among patients with paod that was treated by endovascular intervention using femoral and popliteal percutaneous transluminal balloon angioplasty (ptba). design and setting: this study was local, prospective and longitudinal. it was carried at the second department of internal medicine of charles university hospital in hradec kralove, czech republic. methods: thirty paod patients (20 male and 10 female) were treated by endovascular intervention using femoral and popliteal ptba. the czech version of the international generic european quality of life questionnaire (eq-5d) was applied. results: the statistical evaluation demonstrated that qol presented highly significant statistical dependence on femoral and popliteal ptba (p < 0.0001). conclusion: the results showed that femoral and popliteal ptba had a highly positive effect on the qol of patients with paod.
Surgical reconstruction of the left main coronary artery with patch-angioplasty
Ivo Martinovic, Hans Greve
Journal of Cardiothoracic Surgery , 2011, DOI: 10.1186/1749-8090-6-24
Abstract: Between February 1997 and July 2007, 37 patients with isolated LMCA stenosis were referred for surgical ostial reconstruction. In 27 patients (73%) surgical angioplasties have been performed. All patients were followed up clinically and with transesophageal echocardiography (TEE) and coronary angiography when required.In 10 patients (27%) a LMCA stenosis could not be confirmed. There were no early mortality or perioperative myocardial infarctions. The postoperative course was uneventful in all patients. In 25 patients, TEE demonstrated a wide open main stem flow pattern one to six months after reconstruction of the left main coronary artery with one patch mild aneurysmal dilated.The surgical reconstruction with patch-angioplasty is a safe and effective method for the treatment of proximal and middle LMCA stenosis. Almost one third of the study group had no really LMCA stenosis: antegrade flow pattern remained sustained and the arterial grafts have been spared. In the cases of unclear or suspected LMCA stenosis, cardio-CT can be performed to unmask catheter-induced coronary spasm as the underlying reason for isolated LMCA stenosis.It has been estimated that isolated left main coronary artery (LMCA) stenosis accounts about 1% of all cases of coronary artery disease [1,2]. Isolated ostial stenosis of the LMCA is mostly caused by atherosclerotic plaques [3]. Idiopathic fibromuscular hyperplasia and inflammatory diseases such as post-radiation aortitis, syphilitic- and Takayasu aortitis are rare causes of the LMCA stenosis [4,5]. Isolated LMCA stenosis are diagnosed usually by coronary angiography, but this investigation itself can cause main coronary artery spasms [6]. If these patients are treated by drugs, the 4- and 6-year survivel rates are 65 and 44% respectively [7]. Despite of increasing catheter-based procedures with PTCA and stenting of the LMCA, the results lead clearly to conclusion that the surgical treatment, conventionally by coronary bypass surgery remain
Comparative study of the areas of osteochondral defects produced in the femoral condyles of rabbits treated with gel of sugarcane biopolymer
Albuquerque, Paulo Cezar Vidal Carneiro de;Aguiar, José Lamartine de Andrade;Santos, Saulo Monteiro dos;Pontes Filho, Nicodemus;Mello, Roberto José Vieira de;Costa, Mariana Lúcia Correia Ramos;Albuquerque, Clarissa Miranda Carneiro de;Almeida, Tarciana Mendon?a de S.;Santos, Alessandro Henrique da Silva;Silva, Joacil Carlos da;
Acta Cirurgica Brasileira , 2011, DOI: 10.1590/S0102-86502011000500010
Abstract: purpose: to measure the healed areas of osteochondral defects produced in femoral condyles of rabbits filled with biopolymer sugar cane gel and to compare these with those of the control group at 90, 120 and 180 days. methods: a study was made of 16 new zealand rabbits, 6 and 7 months old, weighing between 2 and 2.5 kg. defects of 3.2 x 4 mm were made, with trephine, in the femoral condyles of the right and left knees. as to the study group defects of the medial and lateral condyles of the right knee were used which were filled with biopolymer sugar cane gel; as to the control group defects of the medial and lateral condyles of the left t knees were used which were left open for natural healing. the defects were analyzed at 90, 120 and 180 days after surgery. after euthanasia, the knees were removed and fixed in bouin's solution for later digital photographic documentation with a digital camera. the areas healed were measured in both the study and control groups using the images obtained from an image-j? program. statistical analysis was conducted using the non-parametric mann-whitney test. results: there were no significant differences between the means of the healed areas in the study and control groups at 90, 120 and 180 days after surgery. conclusion: the dimension of the healed areas of the defects treated with the biopolymer sugar-cane gel in the study group was similar to those of the control group, which healed naturally.
Pericardial Patch Angioplasty Heals via an Ephrin-B2 and CD34 Positive Cell Mediated Mechanism  [PDF]
Xin Li, Caroline Jadlowiec, Yuanyuan Guo, Clinton D. Protack, Kenneth R. Ziegler, Wei Lv, Chenzi Yang, Chang Shu, Alan Dardik
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0038844
Abstract: Objective Pericardial patches are commonly used in vascular surgery to close arteriotomies. The mechanism of early healing after patch implantation is still not well defined. We used a rat aortic patch model to assess pericardial patch healing and examined Ephrin-B2, a marker of arterial identity, expression within the post-implantation patch. We also determined whether endothelial progenitor cells (EPC) are associated with early patch healing in the arterial environment. Methods Wistar rats (200–250 grams) underwent infrarenal aortic arteriotomy and then closure via bovine or porcine pericardial patch angioplasty. Control groups included subcutaneously implanted patches. Patches were harvested at 0–30 days and analyzed by histology, immunohistochemistry, immunofluorescence and Western blot as well as quantitative PCR. Results Prior to implantation, pericardial patches are largely composed of collagen and are acellular. Following arterial implantation, increasing numbers of CD68-positive cells as well as Ephrin-B2 and CD34 dual-positive cells are found within both bovine and porcine pericardial patches, whereas the infiltrating cells are negative for vWF and α-actin. Porcine patches have a luminal monolayer of cells at day 7, compared to bovine patches that have fewer luminal cells. Subcutaneously implanted patches do not attract Ephrin-B2/CD34-positive cells. By day 30, both bovine and porcine pericardial patches develop a neointima that contains Ephrin-B2, CD34, and VEGFR2-positive cells. Conclusion Both CD68-positive and Ephrin-B2 and CD34 dual-positive cells infiltrate the pericardial patch early after implantation. Arteriotomy closure via pericardial patch angioplasty shows patch adaptation to the arterial environment that may involve a foreign body response as well as localization of EPC. Arterial remodeling of pericardial patches support endothelialization and may represent a paradigm of healing of scaffolds used for tissue engineering.
Biopolymer augmentation of the lag screw in the treatment of femoral neck fractures - a biomechanical in-vitro study
A Paech, E Wilde, AP Schulz, G Heinrichs, R Wendlandt, C Queitsch, B Kienast, Ch Jürgens
European Journal of Medical Research , 2010, DOI: 10.1186/2047-783x-15-4-174
Abstract: Concerning the density and compression force of osteoporotic femoral bone polyurethane foam according to the terms of the Association for Standard Testing Material (ASTMF 1839-97) was used as test material. The polyurethane foam Lumoltan 200 with a compression force of 3.3 Mpa and a density of 0.192 g/cm3 was used to reproduce the osteoporotic bone of the femoral fragment (density 12 lbm/ft3). A cylinder of 50 mm of length and 50 mm of width was produced by a rotary splint raising procedure with planar contact.The axial load of the system was performed by a hydraulic force cylinder of a universal test machine type Zwick 1455, Ulm, Germany. The CCD-angle of the used TGN-System was preset at 130 degrees.The migration pattern of the hip screw in the polyurethane foam was measured and expressed as a curve of the distance in millimeter [mm] against the applied load in Newton [N] up to the cut-out point. During the tests the implants reached a critical changing point from stable to unstable with an increased load progression of steps of 50 Newton. This unstable point was characterized by an increased migration speed in millimeters and higher descending gradient in the migration curve. This peak of the migration curve served as an indicator for the change of the hip screw position in the simulated bone material. The applied load in the non-augmented implant showed that in this group for a density degree of 12 (0,192 g/cm3) the mean force at the failure point was 1431 Newton (± 52 Newton). In the augmented implant we found that the mean force at the failure point was 1987 Newton (± 84 Newton). This difference was statistically significant.In conclusion, the bone density is a significant factor for the stability of the hip screw implant. The osteosynthesis with screws in material with low density increases the chance for cut-out. A biopolymer augmented hip screw could significantly improve the stability of the fixation. The use of augmentation with a fast hardening bone repl
Prolene Hernia System, Ultrapro Hernia System and 3D patch devices in the treatment of inguinal, femoral, umbilical and small incisional hernias in outpatient surgery
Dabi? D.,Cerovi? S.,Azanjac B.,Mari? B.
Acta Chirurgica Iugoslavica , 2010, DOI: 10.2298/aci1002049d
Abstract: Introduction: The employment of a diversity of prosthetic materials and several types of mesh different in construction is opening a new chapter in hernia surgery and tension-free techniques are becoming a 'golden standard' for repairing abdominal wall defects, whereas the conventional methods, i.e. the tension techniques are performed on young patients having small direct, indirect, or femoral hernias. Aim: The aim of this retrospective study is to present the results of using Prolene Hernia System (PHS), Ultrapro Hernia System (UHS) and 3D Patch (3DP) devices in the treatment of inguinal, femoral, umbilical and small incisional hernias in outpatient surgery. Material and methods: From January 2006 to January 2009, 70 patients were operated on for abdominal wall hernias (54 inguinal, 4 femoral, 8 umbilical and 4 small incisional hernias) using PHS, UHS and 3DP devices. All the patients underwent surgery under local infiltrative anaesthesia. All the surgical operations were performed by a single surgeon, 19 of them in the General Hospital and 51 in a private polyclinic. Results: The mean size of the hernia defect in the inguinal, femoral and umbilical hernias was 2.5cm (1- 4cm), while in the incisional hernias it was 4.5cm (3- 6cm). The mean operating time was 2.4hrs (2-6hrs). There were no requirement for urinary drains. The mean follow-up was 18 months (0-36 months). The incidence of infection, chronic pain and recurrence was 0%. Three of the patients had complications: seroma in one patient with an incisional hernia and hematoma in two patients after inguinal hernia repair. Conclusion: The employment of PHS, UHS and 3DP devices, which have not yet been widely accepted in our hospitals, has had outstanding results in outpatient surgery. In addition, the type of anaesthesia and the 3D mesh construction prepare the way for a short hospital stay, smooth recovery and a swift return to normal activity.
Subclavian artery angioplasty in elderly patients with coronary-subclavian steal syndrome: preliminary comparison between a modified brachial technique and the standard femoral approach
Gianluca Rigatelli,Paolo Cardaioli,Massimo Giordan,Stefano Panin,Laura Oliva,Tranquillo Milan,Loris Roncon,
Gianluca Rigatelli
,Paolo Cardaioli,Massimo Giordan,Stefano Panin,Laura Oliv,Tranquillo Milan,Loris Roncon

老年心脏病学杂志(英文版) , 2007,
Abstract: Background and Objective Elderly patients who have been submitted to coronary bypass grafting with the left internal mammary artery (LIMA) may develop a coronary-subclavian steal syndrome because of a left subclavian artery (LSA) stenosis. Usually stenting of LSA is performed by the standard femoral route with guiding catheter technique, but this technique can be particularly difficult in elderly patients who often have iliac-femoral kinking and aortic tortuosity. We compared a new "ad hoc" brachial artery approach technique with the standard guiding catheter technique through the femoral access. Methods Between January 2005 and September 2006, four patients underwent LSA stenting using the left brachial artery access obtained with a 6F or 7F 45-cm-long valved anti-kinking sheath as the Super Arrow Flex sheath (Arrow International, PA, USA). The sheath was positioned just before the LIMA graft ostium and a 0.035 inch 260-cm-long Storq guidewire (Cordis Inc., Johnson & Johnson, Warren, NJ) was advanced across the lesion to the descending aorta. A balloon-expandable Genesis (Cordis Inc., Johnson & Johnson, Warren, NJ) endovascular stent was easily deployed, and the correct position was checked by direct contrast injection through the long sheath. This small group of patients has been compared to a group of 5 age-matched patients with coronary steal syndrome in whom the procedure has been performed with standard technique including femoral approach and guide catheter. Results The procedure was successful in all patients; vertebral and LIMA ostia remained patent in all cases. In the control group, cannulation of the subclavian artery was difficult in two cases, while one patient developed a groin hematoma. Mean pretreatment gradient was 32 mm Hg with a range of 25 to 40 mm Hg (34 mmHg, range 26-43, in the control group, P=0.87) and fell to 2 mm Hg with a range of 0 to 4 mm Hg (3.1 mmHg, range 0 to 5, P=0.89) posttreatment. Mean contrast dose was 60±16 ml (138±26 ml in the control group, P>0.01), whereas mean fluoroscopy and procedural time were 5.7±1.6 minutes (10.8±1.0 minutes in the control group, P>0.01) and 15.7±6.3 minutes (28±7.1 minutes in the control group, P>0.01). At a mean follow-up of 10±3.2 months all patients are alive and free from angina and residual induced ischemia. Conclusions Our brief study suggested that brachial artery access be considered the optimal route to treat coronary-subclavian steal syndrome in elderly patients because of clear advantages; these included no manipulation of catheter to cannulate the artery, perfect coaxial position of the catheter at the site of LSA stenosis, clear visualization of the LIMA and vertebral ostia, and easy access to these vessels in case of plaque shifting or embolic protection device deployment.
Systematic Review of Randomized Controlled Trials of Different Types of Patch Materials during Carotid Endarterectomy  [PDF]
Shiyan Ren, Xianlun Li, Jianyan Wen, Wenjian Zhang, Peng Liu
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0055050
Abstract: Background and Purpose Carotid endarterectomy (CEA) with patch angioplasty produces greater results than with primary closure; however, there remains uncertainty on the optimal patch material in CEA. A systematic review of randomized controlled trials (RCTs) was performed to evaluate the effect of angioplasty using venous patch versus synthetic patch material, and Dacron patch versus polytetrafluoroethelene (PTFE) patch material during CEA. Methods A multiple electronic health database screening was performed including the Cochrane library, Pubmed, Ovid, EMBASE and Google Scholar on all randomized controlled trials (RCTs) published before November 2012 that compared the outcomes of patients undergoing CEA with venous patch versus synthetic patch. RCTs were included if they compared carotid patch angioplasty with autologus venous patch versus synthetic patch material, or compared one type of synthetic patch with another. Results Thirteen RCTs were identified. Ten trials, involving 1946 CEAs, compared venous patch with synthetic patch materials. Two trials, involving 400 CEAs in 380 patients, compared Dacron patch with PTFE patch. The hemostasis time in CEA with PTFE patch was significantly longer than with venous patch (P<0.0001), and longer than with Dacron patch (P<0.0001). There was no significant difference of mortality rate, stroke rate, restenosis, and operative time in CEA with venous patch versus synthetic patch material, or in CEA with Dacron patch versus PTFE patch (all P>0.05). One RCT of 95 CEAs in 92 patients compared bovine pericardium with Dacron patch, and demonstrated a statistically significant decrease in intraoperative suture line bleeding with bovine pericardium compared with Dacron patch (P<0.001). Conclusions The hemostasis time in CEA with PTFE patch was longer than with venous patch or Dacron patch. The overall perioperative and long-term mortality rate, stroke rate, restenosis, and operative time were similar when using venous patch versus synthetic patch material or Dacron patch versus PTFE patch material during CEA. More data are required to clarify differences between different patch materials.
Dynamics of forced biopolymer translocation  [PDF]
V. V. Lehtola,R. P. Linna,K. Kaski
Physics , 2009, DOI: 10.1209/0295-5075/85/58006
Abstract: We present results from our simulations of biopolymer translocation in a solvent which explain the main experimental findings. The forced translocation can be described by simple force balance arguments for the relevant range of pore potentials in experiments and biological systems. Scaling of translocation time with polymer length varies with pore force and friction. Hydrodynamics affects this scaling and significantly reduces translocation times.
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