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1.
主动脉瘤是一种多因素影响、具有潜在破裂风险的主动脉病理扩张性疾病。根据发病位置主动脉瘤可分为胸主动脉瘤和腹主动脉瘤。胸主动脉瘤的发生与年龄和性别相关性不大,而与遗传因素高度相关;腹主动脉瘤的发生与年龄、性别、动脉粥样硬化等相关,但与遗传关联性较弱。 主动脉瘤一般具有发病隐匿和破裂致死等特征,是严重威胁人类生命健康的慢性疾病,但其发病机制尚不完全清楚。主动脉瘤动物模型是研究人主动脉瘤的重要工具,对阐释主动脉瘤的病理生理学机制、研发和评价主动脉瘤的治疗药物都具有重要意义。当前关于腹主动脉瘤的动物模型有很多,也比较成熟,但是关于胸主动脉瘤的动物模型较少。实际上,多种方法诱导的腹主动脉瘤模型中,也会出现胸主动脉瘤,只不过发病率不同,胸主动脉瘤的发病率较低。本文将主动脉瘤动物模型归纳为非夹层主动脉瘤动物模型和夹层主动脉瘤动物模型,并简要综述这两类模型的构建方法及表型,为人类动脉瘤的防治研究提供参考。  相似文献   
2.
目的 探讨杂交手术在治疗累及弓部的Stanford B型主动脉夹层(TBAD)中的有效性和安全性。方法 前瞻性描述性研究。纳入2020年1月—2021年9月蚌埠医学院第一附属医院血管外科确诊为累及弓部的TBAD患者。其中男16例,女5例;年龄32~81(59.7±12.9)岁。患者均采用外科转流术和胸主动脉腔内修复术相结合设计的新的杂交手术治疗。观察指标:患者手术时间、术中出血量、术中转流血管通畅情况、有无Ⅰ型内漏、术后卧床时间、住院费用、术后住院时间、术后并发症以及死亡等指标。术后随访观察有无支架移位、再干预、支架内血栓形成、支架内再狭窄、移植物感染、各型内漏,转流血管通畅情况及真腔通畅情况。结果 患者手术均成功,术中均未出现Ⅰ型内漏。手术时间为(156.5±19.7)min,术中出血量为(70.2±25.6)mL,术后卧床时间为(4.3±1.7)d。11例患者使用人工血管行转流术,术后住院时间为(9.6±3.1)d,住院费用为(16.6±3.8)万元;另外10例使用自体大隐静脉,术后住院时间为(14.1±6.3)d,住院费用(剔除2例左颈总动脉植入支架病例)为(13.0±1.2)万元。21例患者术后仅1例出现腔隙性脑梗死,其余均未出现内脏缺血、下肢缺血、急性心功能不全、脑卒中、肺动脉栓塞、脑梗死、肺部感染和急性肾损伤等并发症,无死亡病例。21例患者术后随访时间为6~12(10.9±2.4)个月,所有患者支架无偏移,未发现内漏,支架段主动脉形态优良、真腔及血管旁路血流顺畅。患者均无再干预、支架内血栓形成、支架内再狭窄、移植物感染等情况发生。结论 在短中期的疗效观察中,杂交手术治疗累及弓部的TBAD安全、有效。  相似文献   
3.
ObjectiveTo evaluate the long-term incidence and outcome of aortic interventions for medically managed uncomplicated thoracic aortic dissections.MethodsBetween January 2012 and December 2018, 91 patients were discharged home with an uncomplicated, medically treated aortic dissection (involving the descending aorta with or without aortic arch involvement, no ascending involvement). After a median period of 4 (first quartile: 2, third quartile: 11) months, 30 patients (33%) required an aortic intervention. Patient characteristics, radiographic, treatment, and follow-up data were compared for patients with and without aortic interventions. A competing risk regression model was analyzed to identify independent predictors of aortic intervention and to predict the risk for intervention.ResultsPatients who underwent aortic interventions had significantly larger thoracic (P = .041) and abdominal (P = .015) aortic diameters, the dissection was significantly longer (P = .035), there were more communications between both lumina (P = .040), and the first communication was significantly closer to the left subclavian artery (P = .049). A descending thoracic aortic diameter exceeding 45 mm was predictive for an aortic intervention (P = .001; subdistribution hazard ratio: 3.51). The risk for aortic intervention was 27% ± 10% and 36% ± 11% after 1 and 3 years, respectively. Fourteen patients (47%) underwent thoracic endovascular aortic repair, 11 patients (37%) thoracic endovascular aortic repair and left carotid to subclavian bypass, 3 patients (10%) total arch replacement with the frozen elephant trunk technique, and 2 patients (7%) thoracoabdominal aortic replacement. We observed no in-hospital mortality.ConclusionsThe need for secondary aortic interventions in patients with initially medically managed, uncomplicated descending aortic dissections is substantial. The full spectrum of aortic treatment options (endovascular, hybrid, conventional open surgical) is required in these patients.  相似文献   
4.
【摘要】 C臂CT在血管内介入治疗中的应用越来越广泛,其较高的空间分辨率和术中影像即时采集,为临床提供了更多选择。颅内动脉瘤诊断金标准仍为DSA,C臂CT可提供更多信息辅助动脉瘤诊断。术中即刻获取影像可为支架置放提供参考,较为清晰地显示支架、动脉瘤、弹簧圈等相对位置,这在术后随访中也有相当大的价值。现就C臂CT在颅内动脉瘤诊断、治疗和随访复查中的应用研究进展作一综述。  相似文献   
5.
6.
ObjectivesGuidelines suggest aortic valve replacement (AVR) for low-risk asymptomatic patients. Indications for transcatheter AVR now include low-risk patients, making it imperative to understand state-of-the-art surgical AVR (SAVR) in this population. Therefore, we compared SAVR outcomes in low-risk patients with those expected from Society of Thoracic Surgeons (STS) models and assessed their intermediate-term survival.MethodsFrom January 2005 to January 2017, 3493 isolated SAVRs were performed in 3474 patients with STS predicted risk of mortality <4%. Observed operative mortality and composite major morbidity or mortality were compared with STS-expected outcomes according to calendar year of surgery. Logistic regression analysis was used to identify risk factors for these outcomes. Patients were followed for time-related mortality.ResultsWith 15 observed operative deaths (0.43%) compared with 55 expected (1.6%), the observed:expected ratio was 0.27 for mortality (95% confidence interval [CI], 0.14-0.42), stroke 0.65 (95% CI, 0.41-0.89), and reoperation 0.50 (95% CI, 0.42-0.60). Major morbidity or mortality steadily declined, with probabilities of 8.6%, 6.7%, and 5.2% in 2006, 2011, and 2016, respectively, while STS-expected risk remained at approximately 12%. Mitral valve regurgitation, ventricular hypertrophy, pulmonary, renal, and hepatic failure, coronary artery disease, and earlier surgery date were residual risk factors. Survival was 98%, 91%, and 82% at 1, 5, and 9 years, respectively, superior to that predicted for the US age-race-sex–matched population.ConclusionsSTS risk models overestimate contemporary SAVR risk at a high-volume center, supporting efforts to create a more agile quality assessment program. SAVR in low-risk patients provides durable survival benefit, supporting early surgery and providing a benchmark for transcatheter AVR.  相似文献   
7.
AimsThis review aims to provide an update of available methods for imaging calcification activity and potential therapeutic options.Data SynthesisAortic valve calcification represents the most common heart valve condition requiring treatment among adults in Western societies. No medical therapies are proven to be effective in treating symptoms or reducing disease progression. Therefore, surgical or transcatheter aortic valve replacement remains the only available treatment option. Elevated circulating concentrations of lipoprotein(a) is strongly associated with degenerative aortic stenosis. This relationship was first observed in prospective observational studies, and the causal relationship was confirmed in genetic studies.ConclusionsNew therapeutic targets have been identified and new imaging techniques could be used to test the effectiveness of new agents and further clarify the pathophysiology of AVS. No therapy that specifically lowers Lp (a) levels has been approved for clinical use.  相似文献   
8.
目的探讨急性主动脉夹层患者首发症状与院前延迟的关系,为临床实施院前针对性健康教育提供参考。方法选取急性主动脉夹层患者488例,收集患者首发症状、一般资料、疾病相关因素、院前相关因素及院前时间,分析首发症状与院前延迟的关系。结果患者院前时间为135.5(48.3, 1 735.5) min,其中院前时间≤150 min 253例(51.8%),>150 min(即院前延迟)235例(48.2%);首发症状多为胸背痛[146例(29.9%)],其次为胸前痛124例(25.4%)、腹痛121例(24.8%)。Logistic回归分析发现自觉病情严重程度、胸背痛是院前延迟的保护因素(P<0.01),腹痛、四肢麻木/疼痛是急性主动脉夹层患者院前延迟的危险因素(P<0.05,P<0.01)。结论急性主动脉夹层患者常以胸背痛为首发症状,腹痛与四肢麻木/疼痛非典型症状是导致急性主动脉夹层患者出现院前延迟的主要因素。需对公众加强疾病相关知识的健康教育,早期采取正确的应对方式,积极就医,缩短院前时间。  相似文献   
9.
PurposeTo evaluate the feasibility and accuracy of a radiation-free implantation of a thoracic aortic stent graft employing fiberoptic and electromagnetic tracking in an anthropomorphic phantom.Materials and MethodsAn anthropomorphic phantom was manufactured based on computed tomography (CT) angiography data from a patient. An aortic stent graft application system was equipped with a fiber Bragg gratings and 3 electromagnetic sensors. The stent graft was navigated in the phantom by 3 interventionalists using the tracking data generated by both technologies. One implantation procedure was performed. The technical success of the procedure was evaluated using digital subtraction angiography and CT angiography (before and after the intervention). Tracking accuracy was determined at various anatomical landmarks based on separately acquired fluoroscopic images. The mean/maximum errors were measured for the stent graft application system and the tip/end of the stent graft.ResultsThe procedure resulted in technical success with a mean error below 3 mm for the entire application system and <2 mm for the position of the tip of the stent graft. Navigation/implantation and handling of the device were rated sufficiently accurate and on par with comparable, routinely used stent graft application systems.ConclusionsThe study demonstrates successful stent graft implantation during a thoracic endovascular aortic repair procedure employing advanced guidance techniques and avoiding fluoroscopic imaging. This is an essential step in facilitating the implantation of stent grafts and reducing the health risks associated with ionizing radiation during endovascular procedures.  相似文献   
10.
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