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101.
Effect of Balloon‐Expandable Transcatheter Aortic Valve Replacement Positioning: A Patient‐Specific Numerical Model 下载免费PDF全文
Matteo Bianchi Gil Marom Ram P. Ghosh Harold A. Fernandez James R. Taylor Jr. Marvin J. Slepian Danny Bluestein 《Artificial organs》2016,40(12):E292-E304
Transcatheter aortic valve replacement (TAVR) has emerged as a life‐saving and effective alternative to surgical valve replacement in high‐risk, elderly patients with severe calcific aortic stenosis. Despite its early promise, certain limitations and adverse events, such as suboptimal placement and valve migration, have been reported. In the present study, it was aimed to evaluate the effect of various TAVR deployment locations on the procedural outcome by assessing the risk for valve migration. The deployment of a balloon‐expandable Edwards SAPIEN valve was simulated via finite element analysis in a patient‐specific calcified aortic root, which was reconstructed from CT scans of a retrospective case of valve migration. The deployment location was parametrized in three configurations and the anchorage was quantitatively assessed based on the contact between the stent and the native valve during the deployment and recoil phases. The proximal deployment led to lower contact area between the native leaflets and the stent which poses higher risk for valve migration. The distal and midway positions resulted in comparable outcomes, with the former providing a slightly better anchorage. The approach presented might be used as a predictive tool for procedural planning in order to prevent prosthesis migration and achieve better clinical outcomes. 相似文献
102.
Uberto Fumagalli Riccardo Rosati Stefano De Pascale Matteo Porta Elisa Carlani Alessandra Pestalozza Alessandro Repici 《Journal of gastrointestinal surgery》2016,20(3):494-499
Aim
Surgical myotomy of the lower esophageal sphincter has a 5-year success rate of approximately 91 %. Peroral endoscopic myotomy can provide similar results for controlling dysphagia. Some patients experience either persistent or recurrent dysphagia after myotomy. We present here a retrospective analysis of our experience with redo myotomy for recurrent dysphagia in patients with achalasia.Methods
From March 1996 to February 2015, 234 myotomies for primary or recurrent achalasia were performed in our center. Fifteen patients (6.4 %) had had a previous myotomy and were undergoing surgical redo myotomy (n?=?9) or endoscopic redo myotomy (n?=?6) for recurrent symptoms.Results
Patients presented at a median of 10.4 months after previous myotomy. Median preoperative Eckardt score was 6. Among the nine patients undergoing surgical myotomy, three esophageal perforations occurred intraoperatively (all repaired immediately). Surgery lasted 111 and 62 min on average (median) in the surgical and peroral endoscopic myotomy (POEM) groups, respectively. No postoperative complications occurred in either group. Median postoperative stay was 3 and 2.5 days in the surgical and POEM groups, respectively. In the surgical group, Eckardt score was <3 for seven out of nine patients after a mean follow-up of 19 months; it was <3 for all six patients in the POEM group after a mean follow-up of 5 months.Conclusions
A redo myotomy should be considered in patients who underwent myotomy for achalasia and presenting with recurrent dysphagia. Preliminary results using POEM indicate that the technique can be safely used in patients who have undergone previous surgical myotomy.103.
Deianira Luciani Matteo Cadossi Federico Tesei Eugenio Chiarello Sandro Giannini 《La Chirurgia degli Organi di Movimento》2008,92(3):155-160
Background Viscosupplementation, with hyaluronan derivates injected into the intra-space of osteoarthritic joints, is now widely used
for the treatment of knee osteoarthritis. This study evaluates the results in terms of pain and disability of intra-articular
injections of hyaluronan derivates into the ankle joint in patients suffering from grade II primary or secondary osteoarthritis
of the ankle.
Methods Twenty-one patients with a painful ankle and radiographic evidence of grade II osteoarthritis had three weekly intra-articular
injections of 2 ml of hylan G-F 20 (10 mg/ml) into the ankle joint. The primary clinical outcome measurement was the ankle
osteoarthritis score (AOS) at the baseline, and at 6, 12 and 18 months.
Results Significant improvement of the AOS from baseline was seen after 6 months (p=0.0001). This improvement was maintained over time with no further changes at 12- and 18-month follow-ups. Regarding pain,
the AOS improved over time from the baseline to the 18-month follow up and became statistically significant at the 12- and
18-month follow-ups (p<0.05). 相似文献
104.
105.
Endovascular repair for concomitant multilevel aortic disease. 总被引:2,自引:0,他引:2
Patrizio Castelli Roberto Caronno Gabriele Piffaretti Matteo Tozzi Chiara Lomazzi Domenico Laganà Gianpaolo Carrafiello Salvatore Cuffari 《European journal of cardio-thoracic surgery》2005,28(3):478-482
OBJECTIVE: Patients with multilevel aortic disease represent a small subgroup with the need for extensive surgical treatment at considerable risk. We present our experience of endovascular exclusion for simultaneous thoracic and abdominal aortic disease in four patients. METHODS: Between January 2002 and January 2005, four patients underwent endovascular repair for simultaneous thoracic and abdominal aortic disease. Mean age was 69+/-10 years (range, 60-81). Thoracic lesions included penetrating aortic ulcer (n=2, ruptured=1), atherosclerotic aneurysm (n=1), and chronic type B dissection (n=1). Abdominal aortic disease included atherosclerotic infrarenal (n=3) and juxtarenal (n=1) aortic aneurysms. Thoracic aortic stent-grafts had been the following: Excluder/TAG (n=3) or Talent (n=1) straight tube devices. Abdominal aortic stent-grafts used were as following: Excluder (n=3) or Zenith (n=1). All patients were followed-up with CT-angiography and chest X-rays 1, 4, 12 months after the procedure, and once per year thereafter. RESULTS: Stent-graft deployment was technically successful in all cases. Intraoperative mortality was not observed. Mean procedure time was 94+/-34 min (range, 70-145). Early postoperative complications occurred in one patient that developed acute renal failure but dialysis was not required. Mean hospitalisation was 8+/-5 days (range, 4-15). Late death occurred in one patient for an undetected ruptured thoracic type 1 endoleak. All three survivors are currently well 16.5 months (range, 3-36) after surgery. No neurological complications developed. CONCLUSION: Simultaneous abdominal and thoracic endovascular repair for multilevel aortic disease is feasible and could be a viable alternative in high-risk patients, who otherwise may not be suitable candidates for conventional repair. 相似文献
106.
Fabrizio Rao Giancarlo Garuti Michele Vitacca Paolo Banfi Fabrizio Racca Renato Cutrera Martino Pavone Marina Pedemonte Matteo Schisano Stefania Pedroni Jacopo Casiraghi Andrea Vianello Valeria A Sansone UILDM Respiratory group 《Acta myologica》2021,40(1):8
Respiratory complications are common in the patient with muscular dystrophy. The periodic clinical and instrumental respiratory evaluation is extremely important. Despite the presence in the literature of updated guidelines, patient associations often report lack of knowledge of these pathologies, particularly in peripheral hospitals. The purpose of this work, inspired by the Italian Muscular Dystrophy Association (UILDM) is to improve management of respiratory problems necessary for the management of these patients complex. To this end, the main items that the specialist can meet in the follow-up of these pathologies have been analyzed and discussed, among which the respiratory basal evaluation, the criteria of adaptation to non-invasive ventilation, management of bronchial secretions, situations of respiratory emergency, indications for tracheostomy and the subject of advance directives of treatment (DAT).Key words: respiratory failure, muscular dystrophy, cough efficacy, spirometry, polygraphy, non-invasive ventilation, arterial blood gases, cough machine, invasive ventilation, tracheostomy, mechanical ventilation 相似文献
107.
108.
109.
Libani IV Guy EC Melchiori L Schiro R Ramos P Breda L Scholzen T Chadburn A Liu Y Kernbach M Baron-Lühr B Porotto M de Sousa M Rachmilewitz EA Hood JD Cappellini MD Giardina PJ Grady RW Gerdes J Rivella S 《Blood》2008,112(3):875-885
In β-thalassemia, the mechanism driving ineffective erythropoiesis (IE) is insufficiently understood. We analyzed mice affected by β-thalassemia and observed, unexpectedly, a relatively small increase in apoptosis of their erythroid cells compared with healthy mice. Therefore, we sought to determine whether IE could also be characterized by limited erythroid cell differentiation. In thalassemic mice, we observed that a greater than normal percentage of erythroid cells was in S-phase, exhibiting an erythroblast-like morphology. Thalassemic cells were associated with expression of cell cycle–promoting genes such as EpoR, Jak2, Cyclin-A, Cdk2, and Ki-67 and the antiapoptotic protein Bcl-XL. The cells also differentiated less than normal erythroid ones in vitro. To investigate whether Jak2 could be responsible for the limited cell differentiation, we administered a Jak2 inhibitor, TG101209, to healthy and thalassemic mice. Exposure to TG101209 dramatically decreased the spleen size but also affected anemia. Although our data do not exclude a role for apoptosis in IE, we propose that expansion of the erythroid pool followed by limited cell differentiation exacerbates IE in thalassemia. In addition, these results suggest that use of Jak2 inhibitors has the potential to profoundly change the management of this disorder. 相似文献
110.