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991.
Introduction: Pulmonary vein stenosis (PVS) is a rare but significant complication of pulmonary vein isolation (PVI). Dilation and stent angioplasty have been described but not compared.
Methods and Results: All percutaneous interventions for PVS complicating PVI between December 2000 and March 2007 were reviewed. Acute success, defined as post-intervention stenosis ≤30%, and long-term outcome of dilation versus stent angioplasty were compared. Freedom from restenosis was defined as freedom from repeat intervention. Overall outcome for all interventions was examined. We studied 34 patients with 55 stenotic veins followed for a mean of 25 months. Dilation was performed in 39 veins and stenting in 40 veins (16 primarily, 24 after dilation restenosis). Acute success and restenosis rates were 42% and 72% for dilation versus 95% (P < 0.001) and 33% for stenting. Time to restenosis was greater for stent angioplasty (P = 0.003). Stents ≥10 mm in diameter had lower restenosis than smaller stents. Risk factors for restenosis included small reference vessel diameter and longer time from PVI to intervention for PVS. All but two patients experienced improvement (n = 10) or resolution of symptoms (n = 22). The mean percent stenosis decreased from 82% to 21% for the entire cohort and mean flow to the lung quadrant increased from 10% to 17%.
Conclusion: Stent angioplasty results in less restenosis than dilation, particularly for stents ≥10 mm. Early referral may improve long-term patency by minimizing reference vessel atrophy. Most patients with PVS post-PVI can be improved symptomatically with catheter intervention.  相似文献   
992.
Percutaneous transcatheter interventions for valve replacement or implantation is one of the most exciting developments in the field of interventional cardiology. Valvular stenosis has been treated by balloon dilatation with early and late results; however, treatment for valvular regurgitation has remained surgical until now. Most new designs have been investigated for implantation of valves in the left or right ventricular outflow tracts. Patients with surgery on the right ventricular outflow tract for congenital heart disease constitute the most common group for reoperations during late follow-up. Surgical pulmonary valve replacement can be performed with low mortality; however, it sets up a substrate for future operations. Also, the risk of cardiopulmonary bypass, infection, bleeding, and ventricular dysfunction remains. A transcatheter technique is likely to have more acceptance and may expand the indications for early intervention for right ventricular outflow tract dysfunction.  相似文献   
993.
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995.
盐酸氨溴索口服溶液改善COPD患者咳痰困难的疗效   总被引:1,自引:0,他引:1  
目的 观察盐酸氨溴索口服溶液对慢性阻塞性肺部疾病(COPD)患者咳痰困难的临床疗效。方法96例COPD伴有咳痰困难患者随机分成2组,治疗组给予盐酸氨溴索口服溶液,对照组给予必嗽平,两组同时给予常规抗生素,观察给药前后患者咳嗽、咳痰的轻重程度,比较患者住院病程的长短,并记录不良反应。结果盐酸氨溴索组总有效率100%,平均住院时间为8.9天,对照组有效率不足84%,平均住院时间12.8天,两组之间疗效有显著性差异,盐酸氨溴索组副反应轻微且发生率低。结论盐酸氨溴索口服溶液在改善COPD患者咳嗽、咳痰方面明显优于对照组,可提高抗生素疗效,缩短患者住院时间,有疗效佳、起效快、副作用小等优点。  相似文献   
996.
The term ‘emphysema’ is generally used in a morphological sense, and therefore imaging modalities have an important role in diagnosing this disease. In particular, high resolution computed tomography (HRCT) is a reliable tool for demonstrating the pathology of emphysema, even in subtle changes within secondary pulmonary lobules. Generally, pulmonary emphysema is classified into three types related to the lobular anatomy: centrilobular emphysema, panlobular emphysema, and paraseptal emphysema. In this pictorial review, we discuss the radiological – pathological correlation in each type of pulmonary emphysema. HRCT of early centrilobular emphysema shows an evenly distributed centrilobular tiny areas of low attenuation with ill-defined borders. With enlargement of the dilated airspace, the surrounding lung parenchyma is compressed, which enables observation of a clear border between the emphysematous area and the normal lung. Because the disease progresses from the centrilobular portion, normal lung parenchyma in the perilobular portion tends to be preserved, even in a case of far-advanced pulmonary emphysema. In panlobular emphysema, HRCT shows either panlobular low attenuation or ill-defined diffuse low attenuation of the lung. Paraseptal emphysema is characterized by subpleural well-defined cystic spaces. Recent topics related to imaging of pulmonary emphysema will also be discussed, including morphometry of the airway in cases of chronic obstructive pulmonary disease, combined pulmonary fibrosis and pulmonary emphysema, and bronchogenic carcinoma associated with bullous lung disease.  相似文献   
997.
998.
Dyskeratosis congenita (DC) is a rare inherited disorder often associated with aplastic anaemia. We report the cases of five boys transplanted with an HLA-identical related donor for severe aplastic anaemia (SAA) associated to DC; in all cases successful engraftment was observed. Three patients died 2–8 years after bone marrow transplantation (BMT) with signs of endothelial cell damage syndrome (kidney microangiopathy and liver veno-occlusive disease). Another boy died 1 year after BMT from Evans syndrome and invasive aspergillosis. One boy currently presents anaemia, polyarthritis of unknown origin, pulmonary fibrosis and gut malabsorption 7.5 years after BMT. SAA associated with DC can be successfully treated by allogeneic BMT. However, these early and late complications observed are very unusual after BMT and probably reflect the association of transplanted-related factors, evolution of the underlying disease, and increased sensitivity of endothelial cells. Modified conditioning approaches, advances in supportive care and surveillance of these unusual complications offer the possibility of improved outcome for these patients.  相似文献   
999.
There is no gold standard for the measurement of pulmonary regurgitation (PR) severity. Two-dimensional (2D) transthoracic echocardiography is most commonly used to quantify PR severity using color Doppler criteria for aortic regurgitation. However, this method is limited by visualization of only one or two dimensions of the proximal PR jet or vena contracta (VC) precluding accurate assessment of its shape or size. This limitation would be expected to be obviated by three-dimensional (3D) transthoracic echocardiography, which could provide a more accurate quantitative assessment of PR severity. This study evaluated 82 adult patients with PR using 2D and 3D. PR VC area by 3D was obtained by planimetry by positioning the cropping plane exactly parallel to the VC, which was viewed en face by cropping of the 3D data set. Regurgitant volumes were calculated by 2D (assuming a circular VC) and by 3D as a product of the VC and velocity time integral obtained by color Doppler-guided conventional Doppler interrogation of the PR jet.The 3D VC area correlated with 2D jet width (JW)/right ventricular outflow tract (RVOT) width (r = 0.71) and 2D VC area (r = 0.79). 3D JW/RVOT width correlated with 2D JW/RVOT (r = 0.87). 3D regurgitant volumes also correlated with 2D regurgitant volumes (r = 0.76). The 3D VC values of <0.20, 0.20-0.45, 0.46-1.15, and >1.15 cm(2) and regurgitant volumes of <15 ml, 15-50 ml, 51-115 ml, and >115 ml were effective as cutoffs for grades 1, 2, 3, and 4 PR, respectively. In conclusion, quantification of 3D VC area and regurgitant volumes correlate reasonably well with the current 2D methods for measurement of PR. Since 3D visualizes PR VC in three dimensions, it would be expected to provide a more accurate and more quantitative assessment of PR severity as compared to 2D.  相似文献   
1000.
重庆市世行贷款/英国赠款中国结核病控制项目中期评估   总被引:3,自引:0,他引:3  
目的 评价重庆市世行贷款/英国赠款中国结核病控制项目的 实施情况,为制定项目中期调整计划提供科学依据.方法 根据卫生部的中期评估调查表,收集2002-2005年全市40个区县常规监测等相关资料,汇总分析.结果 项目覆盖全市40个区县,DOTS覆盖率100%;4年来可疑者就诊率由16.90/万到28.38/万,提高了67.8%;新发涂阳病人登记率由31.54/10万到44.27/10万,提高了40.4%;初治涂阳病人治愈率94.1%,复治涂阳病人治愈率88.9%.结论 项目实施4年达到中期目标和全球结核病控制阶段性目标.但要控制结核病疫情,确保〈规划〉目标的全面实现,任务艰巨,任重而道远.  相似文献   
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