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Thoracic endovascular aortic repair (TEVAR) for aneurysmal chronic dissection is often complicated by retrograde filling of the false lumen and dissected distal landing zone. A “cheese wire”-style fenestration of the dissection intimal flap can create a landing zone facilitating TEVAR. This technique successfully aided TEVAR in 3 patients with an average age of 57.3 years. Complications included type III endoleak requiring relining and renal artery occlusion requiring stent placement. Average duration of clinical follow-up was 19 ± 4 months. Imaging follow-up was 8 ± 10 months. All patients have survived for more than 1 year without aneurysm enlargement.  相似文献   
3.
We report the case of a 4-year-old girl who had quadricuspid aortic valve regurgitation with tetralogy of Fallot and pulmonary atresia. This combination is very uncommon. Aortic valve replacement was performed successfully due to aortic regurgitation which had progressed one year after the total repair. The dilated aortic annulus plus quadricuspid aortic valve may result in progressive aortic regurgitation for a short period.  相似文献   
4.
Summary Previous studies of Alcian blue-induced birefringence in adult avian cortical bone showed that a short period of intermittent loading rapidly produces an increased level of orientation of proteoglycans within the bone tissue. In the absence of further loading, this persists for over 24 hours. We have proposed that this phenomenon could provide a means for “capturing” the effects of transient strains, and so provide a persistent, constantly updated strain-related influence on osteocyte populations related to the bones' averaged recent strain history, in effect, a “strain memory” in bone tissue. In our present study, we use the Alcian blue-induced birefringence technique to demonstrate that proteoglycan orientation also occurs after intermittent loading of both cortical and cancellous mammalian bonein vivo andin vitro. We also show that the change in birefringence is proportional to the magnitude of the applied strain, and that the reorientation occurs rapidly, reaching a maximal value after only 50 loading cycles. Examination of electron micrographs of bone tissue after staining with cupromeronic blue allows direct visualization and quantification of the change in proteoglycan orientation produced by loading. This shows that intermittent loading is associated with a realignment of the proteoglycan protein cores, bringing them some 5 degrees closer to the direction of collagen fibrils in the bone matrix.  相似文献   
5.
目的我们应用平衡法门控心血池显像技术对不同Killip分级的前壁心肌梗死患者进行左室总体和局部收缩和舒张功能参数的对比分析。方法对照组15例(G0),前壁心肌梗死KillipⅠ级17例(G1),前壁心肌梗死KillipⅡⅢ级12例(G2)。利用平衡法门控心血池显像技术评价3组的左室总体和局部的收缩与舒张功能。结果①左室整体收缩功能,在LVEF,ESC 2个参数中,G1比G0有显著差异(P<0.05),G2分别比G1和G0有显著差异(P<0.05)。在PER、1/3EF、1/3ER 3个参数中,G2分别比G1和G0显著下降(P<0.05)。②左室总体舒张功能,在PFR、1/3FF、1/3FR、EDC中,G1比G0有显著差异(P<0.05),G2分别比G1和G0有显著差异(P<0.05)。③左室局部收缩功能,在以LVREF为参数时,G1在4个节段比G0显著差异(P<0.05),G2在所有6个节段中比G1和G0均显著下降(P<0.05)。④左室局部舒张功能,在以LVR1/3FF为参数时,G1在4个节段比G0显著下降(P<0.05),G2在所有6个节段比G0和G1均显著下降(P<0.05)。结论前壁心肌梗死后出现心功能受损或心力衰竭的主要原因为左室重构。  相似文献   
6.
Background and aims Since the introduction of endovascular aortic aneurysm repair (EVAR) for aortic aneurysms, the number of juxtarenal aortic aneurysms (JRA) has been growing steadily due to selection bias (neck morphology for EVAR). This case-match study compares the perioperative outcome and midterm results of suprarenally clamped JRA with infrarenal aortic aneurysms (AAA). Methods From 1997 to 2004, patients who received open surgery with suprarenal clamping for JRA were included in the study and compared to matched patients with infrarenal clamping (AAA). Measurements analyzed were the in-hospital mortality and morbidity. Midterm results were obtained through clinical investigation and magnetic resonance angiography imaging. Results Thirty-five patients (mean age, 68.4 years; 30 male and 5 female) received suprarenal cross-clamping for JRA. The overall in-hospital mortality for JRA and for the controls (AAA) with elective aortic repair was 4.5% (6.1% JRA; 3% AAA, p = 0.058). The morbidity of JRA was elevated according to the rate of pulmonary complications (p = 0.021) and the need for re-operation (p = 0.019). The mean follow-up time was 2.3 years (range, 8–96 months). At follow-up, 28 patients (80%) from the JRA group and 29 patients from the AAA group (82.9%) were alive. Conclusion Open aortic surgery for JRA with the need for suprarenal cross-clamping shows a slightly elevated in-hospital mortality rate without statistical significance and equal midterm mortality results in comparison with infrarenally clamped aortic aneurysms.  相似文献   
7.
OBJECTIVE: Colonic infarction is a recognized complication of abdominal aortic aneurysm (AAA) surgery. The clinical difficulty in establishing the diagnosis combined with the patient's poor physiological status is usually associated with a fatal outcome. We assessed our experience with this problem to identify a possible risk factor profile for these patients. METHOD: Patients records were identified from the operative logs, intensive care unit, Hospital Inpatient Enquiry system and vascular unit databases over a 6-year period. RESULTS: A total of 405 patients underwent AAA repair during this period; 140 as emergency ruptures. Nine patients were identified from the databases with known colonic infarction (2.2%). One was a woman. The mean age was 70 years. Seven patients had emergency ruptures (5%). Twenty independent risk factors were analysed using univariate and multivariate logistic regression models. Significant risk factors identified by using a multivariate analysis included the nature of the presenting patient, preoperative hypotension, prolonged cross-clamp time, intra-operative ischaemia and postoperative acidosis. Confirmatory diagnosis was made by colonoscopy in eight patients. One patient survived following the salvage surgery. The mean duration of survival was 10.5 days. The overall mortality was 89% of patients. CONCLUSION: In our unit infrarenal AAA repair has a 2.2% rate of colonic infarction. A definitive diagnosis is best made by colonoscopy. A risk factor profile for the development of colonic infarction may be constructed on the basis of specific clinical parameters. Earlier intervention on the basis of this profile may ultimately reduce the current excessive mortality.  相似文献   
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9.
应用同种动脉治疗主动脉根部病变   总被引:4,自引:0,他引:4  
报告5例采用同种动脉(HAV)治疗5例主动脉根部病变(主动脉瓣狭窄1例,关闭不全4例)。男3例,女2例;年龄13~47岁。病因为细菌性心内膜炎2例(包括先天主动脉瓣二瓣化畸型1例),Marfan综合征2例,风湿性主动脉瓣关闭不全1例。术中采用同种主动脉全根置换3例(Bentall手术),其中1例用HAV上的二尖瓣前叶加宽主动脉瓣环(Manouguian手术),余2例用自体肺动脉移置主动脉根部,另取同种肺动脉做原位移置(Ross手术)。结果死亡1冽,4例存活,且无并发症发生。术后超声心动图提示主动脉根部良好,无主动脉瓣反流。随访2.5~3.5年疗效满意。  相似文献   
10.
徐育红  王建安 《浙江医学》2004,26(6):407-409
目的探讨原发性高血压(EH)患者微量白蛋白尿(MCA)与血压及左室重塑的关系.方法 84名EH患者按24h尿微量白蛋白值分为微量白蛋白尿组(MCA组)和正常白蛋白尿组(NMCA组),进行动态血压、心脏超声检测,比较两组动态血压值、左室重量指数(LVMI)及左室重塑的特点.结果 MCA组平均收缩压、平均舒张压、脉压、平均动脉压均高于NMCA组(均P<0.01);MCA组LVMI、左室肥厚与向心性肥厚的发生率均高于NMCA组(均P<0.01),正常构型率低于NMCA组(P=0.01).LVMI与尿微量白蛋白值、平均收缩压、平均舒张压均呈显著的正相关(均P<0.05).结论合并有MCA的EH患者血压较高,LVMI较大,左室肥厚与向心性肥厚的发生率较高.MCA与血压及左室重塑密切相关.  相似文献   
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