MicroRNAs, fibrotic remodeling, and aortic aneurysms

Aortic aneurysms are a common clinical condition that can cause death due to aortic dissection or rupture. The association between aortic aneurysm pathogenesis and altered TGF-β signaling has been the subject of numerous investigations. Recently, a TGF-β-responsive microRNA (miR), miR-29, has been identified to play a role in cellular phenotypic modulation during aortic development and aging. In this issue of JCI, Maegdefessel and colleagues demonstrate that decreasing the levels of miR-29b in the aortic wall can attenuate aortic aneurysm progression in two different mouse models of abdominal aortic aneurysms. This study highlights the relevance of miR-29b in aortic disease but also raises questions about its specific role.     

Involvement of the renin-angiotensin system in abdominal and thoracic aortic aneurysms

Aortic aneurysms are relatively common maladies that may lead to the devastating consequence of aortic rupture. AAAs (abdominal aortic aneurysms) and TAAs (thoracic aortic aneurysms) are two common forms of aneurysmal diseases in humans that appear to have distinct pathologies and mechanisms. Despite this divergence, there are numerous and consistent demonstrations that overactivation of the RAS (renin-angiotensin system) promotes both AAAs and TAAs in animal models. For example, in mice, both AAAs and TAAs are formed during infusion of AngII (angiotensin II), the major bioactive peptide in the RAS. There are many proposed mechanisms by which the RAS initiates and perpetuates aortic aneurysms, including effects of AngII on a diverse array of cell types and mediators. These experimental findings are complemented in humans by genetic association studies and retrospective analyses of clinical data that generally support a role of the RAS in both AAAs and TAAs. Given the lack of a validated pharmacological therapy for any form of aortic aneurysm, there is a pressing need to determine whether the consistent findings on the role of the RAS in animal models are translatable to humans afflicted with these diseases. The present review compiles the recent literature that has shown the RAS as a critical component in the pathogenesis of aortic aneurysms.     

Abdominal aortic aneurysms: clinical features, treatment and care

Aneurysms can occur in any blood vessel, but aortic aneurysms in the abdominal aorta are particularly common. Large aortic aneurysms are likely to progress to life-threatening rupture or dissection, which is usually fatal. Elective repair of large aneurysms therefore reduces mortality and morbidity. Small aneurysms may be present in patients who present with other conditions. They will be monitored, but do not usually warrant the risks of undertaking repair on the body's main artery. This article reviews the pathophysiology, medical treatments and nursing care of abdominal aortic aneurysms.     

Splanchnic artery aneurysms

Autopsy studies suggest that splanchnic artery aneurysms may be more frequent than abdominal aortic aneurysms. These aneurysms are important to recognize because up to 25% may be complicated by rupture, and the mortality rate after rupture is between 25% and 70%. However, little is known about the natural history and clinical presentation of splanchnic artery aneurysms. Splenic artery aneurysms are the most common of the splanchnic artery aneurysms; multiple aneurysms are present in approximately one third of patients. Hepatic artery pseudoaneurysms are more common than true aneurysms because of increasing numbers of hepatobiliary interventional procedures. The diagnosis of splanchnic artery aneurysm should be considered in any patient with abdominal pain, a pulsatile mass, or an abdominal bruit with or without associated bleeding. However, most aneurysms are asymptomatic and are detected incidentally on imaging studies. Treatment, which can be either surgical or interventional radiology-based, should be considered in all patients with symptoms related to the aneurysms, if the aneurysm is more than 2 cm in diameter, if the patient is pregnant, or if there is demonstrated growth of the aneurysm.     

胸主动脉瘤手术治疗89例分析

目的 分析89例胸主动脉瘤手术治疗的临床资料,总结手术治疗胸主动脉瘤的经验.探讨胸主动脉瘤手术治疗的手术适应证、手术方式的新进展,探讨胸主动脉瘤的病因及临床表现,提出早期干预措施.方法术前评估每位患者病情特点,采用多种不同的手术方式.结果 手术成功85例,手术成功率为95.5%;有4例术后早期死亡,术后早期病死率为4.5%.结论 胸主动脉瘤手术治疗方法安全、有效.     

三维增强MR血管成像在主动脉瘤诊治中的临床价值

目的评价三维增强MR血管成像（3D CE-MRA）在主动脉瘤诊治中的临床价值。材料与方法 925例主动脉瘤患者行3D CE-MRA检查,工作站上三维重建,探讨图像在制定治疗方案中的作用。结果 925例主动脉瘤中,真性动脉瘤479例（胸段138例,胸腹段29例,腹段312例）,主动脉夹层407例（Stanford A型84例,B型232例,主动脉壁内血肿91例）,假性动脉瘤39例（胸段21例,腹段18例）。3D CE-MRA立体显示各种动脉瘤类型、形态、部位、病变细节及其与邻近动脉分支的关系,与行腔内隔绝术的DSA比较,3D CE-MRA所测参数与DSA高度一致（P〉0.05）,对临床治疗方案的制定具有重要指导作用。925例中,352例行腔内隔绝术（真性动脉瘤195例,主动脉夹层126例,假性动脉瘤31例）,115例行手术治疗（真性动脉瘤47例,主动脉夹层63例,假性动脉瘤5例）。结论 3D CEMRA能无创、快速、有效诊断主动脉瘤,为手术或腔内隔绝术提供较为全面的信息,可作为主动脉瘤患者,尤其是伴有肾功能不全患者的首选诊断方法。     

血管急诊回顾

急诊科医生往往是重症患者的首诊医生,当疾病特征明显,诊断难度不大。但当临床表现模棱两可时,就需要一个标准化的检查流程以决定是否需要急诊治疗。血管急诊时常有较严重的临床后果,因而必须早诊断,往往在患者检查分类时就需考虑血管急诊的可能性。     

Inflammation, infection, cavitary disorders, and ischemia.

Demyclinating lesions of the spinal cord, including multiple sclerosis as well as other less common diseases, probably represent the etiology of a substantial proportion of all idiopathic myelopathies. Magnetic resonance imaging (MRI) has made major advances in the diagnosis and characterization of demyclinating disease. Infections of the spine may have severe consequences and, if detected early, are usually treatable processes. Osteomyelitis and epidural abscesses have characteristic imaging findings. Poor outcomes are more often due to delays in clinical presentation or the debilitated condition of the patients than to limitations in the accuracy of MRI diagnosis. Cavitary lesions of the spinal cord were among the first applications in which MRI proved its superiority to previously available techniques. Accurate diagnosis of these lesions involves detecting characteristics findings and relating these observations to the clinical history. Spinal cord infarction is relatively rare due to the extensively collateralized blood supply to the spinal canal. However, aortic aneurysms and the surgery for these lesions places the blood supply of the distal spinal cord and conus at risk. The syndrome of postoperative spinal cord infarction has characteristic clinical findings. However, MRI may contribute to distinguishing transient ischemia from true infarction and to predicting the severity of the final deficit.     

腹主动脉瘤合并高血压患者介入室内行腔内隔绝术的围手术期护理

目的 探讨腹主动脉瘤腔内修复术的围手术期护理要点。方法 对8例腹主动脉瘤合并高血压的患者于术前做好人院指导及心理护理，调整其心理状态以适应手术，防止腹主动脉瘤破裂；术中注意麻醉前及气管插管时血流动力学的剧烈波动，调控及密切观察血压的变化，防治心律失常；术后做好各种管道的护理观察，密切各种并发症的观察及护理。结果 8例腹主动脉瘤合并高血压患者移植物全部成功置入，术后黑便1例，发热1例，经及时治疗与护理病情恢复良好，未出现肾功能衰竭及下肢血栓形成。患者均在术后2周内康复出院。结论 腹主动脉瘤腔内修复治疗系微创手术，但患者多合并一定的并发症，且手术本身亦有一定的并发症，加强围手术期护理，预防并及时处理并发症是提高手术成功率，保障患者痊愈的重要环节。     

Acute aortic dissection in women: challenges and opportunities

Acute aortic dissection (AAD) is a severe and potentially fatal disease which requires rapid diagnosis and appropriate treatment in order to improve survival. The variable and sometimes non-specific presentation of this rare condition makes it a continued diagnostic challenge for even the best of clinicians. Multiple clinical factors have been studied for their role in increasing the risk of AAD. While the complete pathophysiology of the condition is not known, contemporary research has shed light on many important factors that might lead to the development of aortic aneurysms and AAD. Despite continued research in this area, there is scant research looking at gender-related differences in the epidemiology, presentation, treatment and outcomes of patients with AAD. This review first revisits lessons about gender-related differences seen in various cardiovascular diseases, and then critically examines the data on gender-related differences in AAD diagnosis, management and outcomes. A summary of the pathophysiology and possible reasons for gender-specific differences in the development of aneurysms and dissections is also provided.     

腹主动脉瘤合并高血压患者介入室内行腔内隔绝术的围手术期护理

目的探讨腹主动脉瘤腔内修复术的围手术期护理要点。方法对8例腹主动脉瘤合并高血压的患者于术前做好入院指导及心理护理,调整其心理状态以适应手术,防止腹主动脉瘤破裂;术中注意麻醉前及气管插管时血流动力学的剧烈波动,调控及密切观察血压的变化,防治心律失常;术后做好各种管道的护理观察,密切各种并发症的观察及护理。结果8例腹主动脉瘤合并高血压患者移植物全部成功置入,术后黑便1例,发热1例,经及时治疗与护理病情恢复良好,未出现肾功能衰竭及下肢血栓形成。患者均在术后2周内康复出院。结论腹主动脉瘤腔内修复治疗系微创手术,但患者多合并一定的并发症,且手术本身亦有一定的并发症,加强围手术期护理,预防并及时处理并发症是提高手术成功率,保障患者痊愈的重要环节。     

Multi-institutional pivotal trial of the Zenith TX2 thoracic aortic stent-graft for treatment of descending thoracic aortic aneurysms: clinical study design

Despite significant improvements in surgical techniques and perioperative management, the repair of descending thoracic aortic aneurysms remains a challenge with the potential for substantial morbidity and mortality. Over the past several years, buoyed by the technical success of endovascular repair of infrarenal abdominal aortic aneurysms, several case series reports of endovascular stent-graft placement for descending thoracic aortic aneurysms have demonstrated the potential safety and efficacy of this treatment modality. Several single-institution studies have documented promising results with these devices, but without controlled clinical trials, the data are insufficient to determine if thoracic aortic endografts provide equivalent or improved outcomes compared with standard open repair. We describe a study design of an ongoing prospective, nonrandomized, multi-institutional, investigational device exemption phase II pivotal clinical trial investigating the safety and effectiveness of the Zenith TX2 thoracic aortic endovascular graft in the elective treatment of patients with descending thoracic aortic aneurysms.     

Emerging strategies to treat ruptured abdominal aortic aneurysms

Population screening programmes and a falling population prevalence of smoking have led to a declining incidence of ruptured abdominal aortic aneurysms in men. However, ruptured abdominal aortic aneurysms remain a common vascular surgical emergency, with an increasing proportion of ruptures being in women. About one quarter of the ruptures have a juxta-renal aneurysm and are more challenging to repair using endovascular technologies. Endovascular technologies may not reduce the overall mortality, compared with open surgical repair, but appear to offer early benefits with respect to patient quality of life at acceptable cost. Challenges over the next 5 years include widening the access to repair, developing an accurate bedside risk scoring tool, as well as optimising strategies for pre-operative resuscitation, standardising peri-operative care and the management of post-operative complications.     

The role of multi-modality imaging for sinus of Valsalva aneurysms

Sinus of Valsalva aneurysms (SVAs) are uncommon but important entities. They are most often congenital in origin, resulting from incomplete fusion of the aortic media to the aortic valve annulus. Less frequently, they may be acquired, usually secondary to infective endocarditis. Unruptured aneurysms may be clinically silent and diagnosed incidentally, but can also produce symptoms as a consequence of mass effect on related structures. Rupture may present with sudden hemodynamic collapse but can have a more insidious onset depending upon the site and size of the perforation. Early diagnosis is imperative and can usually be made reliably by transthoracic echocardiography. However, transesophageal echocardiography may sometimes be required for confirmation. Cardiovascular magnetic resonance imaging (CMRI) and multi-detector computed tomography are being increasingly utilized for evaluation of SVAs and can offer valuable complimentary information. CMRI in particular enables a comprehensive assessment of anatomy, function and flow in a single sitting. Surgical repair forms the mainstay of treatment for both ruptured and unruptured aneurysms and has low complication rates. This article provides an overview of the pathological and clinical aspects of SVAs and discusses in detail the role of advanced imaging modalities in their evaluation.     

Strain estimation in abdominal aortic aneurysms from 2-D ultrasound

The rupture risk of abdominal aortic aneurysms (AAAs) is routinely inferred from the maximum diameter of the AAA. However, clinical experience indicates that this criterion has poor accuracy and that noninvasive assessment of the elastic properties of the vessel might give better correspondence with the rupture risk. We have developed a method for analysis of circumferential strain in AAAs from sequences of cross-sectional ultrasound B-mode images. The algorithm is fast, semiautomatic and well-suited for real-time applications. The method was developed and evaluated using data from 10 AAA patients. The preliminary results demonstrate that the method is sufficiently accurate and robust for clinically acquired data. An important finding is that local strain values may exceed the circumferential average strain significantly. Furthermore, the calculated strain shows no apparent covariation with the diagnosed diameter. This implies that the method may give new and essential information on the clinical condition of the AAA.     

44例主动脉夹层临床分析

目的 探讨主动脉夹层患者的患病危险因素、临床特征、诊治方法及预后.方法 对我院2005-2008年诊治的44例主动脉夹层患者临床资料进行回顾性分析.结果 主动脉夹层发生的常见病因是高血压.首发表现以胸痛为常见(部分病例以并发症为首发).CT和MRI检查对主动脉夹层的确诊率较超声检查高,但由于超声检查价格便宜,床旁操作方便,故有疑诊患者,可做常规超声检查.主动脉夹层的治疗有内科保守治疗,外科手术治疗和血管内带膜支架治疗.结论 高血压是主动脉夹层的主要危险因素,其临床表现复杂多变,误诊率高.内科治疗时血压控制多需多种降压药物联合应用,然而根据临床分型和病情采取外科手术、介入治疗可降低病死率和改善患者的预后.     

44例主动脉夹层临床分析

目的 探讨主动脉夹层患者的患病危险因素、临床特征、诊治方法及预后.方法 对我院2005-2008年诊治的44例主动脉夹层患者临床资料进行回顾性分析.结果 主动脉夹层发生的常见病因是高血压.首发表现以胸痛为常见(部分病例以并发症为首发).CT和MRI检查对主动脉夹层的确诊率较超声检查高,但由于超声检查价格便宜,床旁操作方便,故有疑诊患者,可做常规超声检查.主动脉夹层的治疗有内科保守治疗,外科手术治疗和血管内带膜支架治疗.结论 高血压是主动脉夹层的主要危险因素,其临床表现复杂多变,误诊率高.内科治疗时血压控制多需多种降压药物联合应用,然而根据临床分型和病情采取外科手术、介入治疗可降低病死率和改善患者的预后.     

44例主动脉夹层临床分析

目的 探讨主动脉夹层患者的患病危险因素、临床特征、诊治方法及预后.方法 对我院2005-2008年诊治的44例主动脉夹层患者临床资料进行回顾性分析.结果 主动脉夹层发生的常见病因是高血压.首发表现以胸痛为常见(部分病例以并发症为首发).CT和MRI检查对主动脉夹层的确诊率较超声检查高,但由于超声检查价格便宜,床旁操作方便,故有疑诊患者,可做常规超声检查.主动脉夹层的治疗有内科保守治疗,外科手术治疗和血管内带膜支架治疗.结论 高血压是主动脉夹层的主要危险因素,其临床表现复杂多变,误诊率高.内科治疗时血压控制多需多种降压药物联合应用,然而根据临床分型和病情采取外科手术、介入治疗可降低病死率和改善患者的预后.     

A simple technique to determine the extent of abdominal aortic aneurysms of B-mode sonography

A simple technique is presented to evaluate extension of abdominal aortic aneurysms above the level of the renal arteries at sonography. Knowledge of such extension is important because these cases may require a thoroacoabdominal surgical approach. Iliac extension of abdominal aortic aneurysms also may be evaluated by sonography.     

Adaptive cellular immunity in aortic aneurysms: cause, consequence, or context?

Abdominal aortic aneurysms are common and life threatening. Although CD4(+) T cells are abundant in aneurysm tissue, their role in disease progression remains unclear. A new study shows that mouse aortic allografts placed in animals lacking IFN-gamma receptors develop a Th2 inflammatory response with aortic aneurysms, whereas Th1 responses promote intimal hyperplasia. It is expected that these surprising findings will stimulate further efforts to clarify whether adaptive cellular immunity in aneurysm disease is detrimental or potentially beneficial.