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171.
172.
《Annals of medicine》2013,45(6):441-446
Acute aortic dissection (AAD) is a life-threatening disease with an incidence of about 2.6–3.6 cases per 100,000/year. Depending on the site of rupture, AAD is classified as Stanford-A when the ascending aortic thoracic tract and/or the arch are involved, and Stanford-B when the descending thoracic aorta and/or aortic abdominal tract are targeted. It was recently shown that inflammatory pathways underlie aortic rupture in both type A and type B Stanford AAD. An immune infiltrate has been found within the middle and outer tunics of dissected aortic specimens. It has also been observed that the recall and activation of macrophages inside the middle tunic are key events in the early phases of AAD. Macrophages are able to release metalloproteinases (MMPs) and pro-inflammatory cytokines which, in turn, give rise to matrix degradation and neoangiogenesis. An imbalance between the production of MMPs and MMP tissue inhibitors is pivotal in the extracellular matrix degradation underlying aortic wall remodelling in dissections occurring both in inherited conditions and in atherosclerosis. Among MMPs, MMP-12 is considered a specific marker of aortic wall disease, whatever the genetic predisposition may be. The aim of this review is, therefore, to take a close look at the immune-inflammatory mechanisms underlying Stanford-A AAD.  相似文献   
173.
Abstract

In this study we aimed to evaluate the efficiency of percutaneous endovascular aortic aneurysm repair (p-EVAR). Anatomically selected patients treated with a single 10Fr Perclose Prostar XL vascular closure device (VCD) were examined. Primary success rate and common femoral artery (CFA) open conversion (OC) requirement per sheath size used were recorded. A literature review on p-EVAR results was also performed. One-hundred patients were enrolled. Successful p-EVAR was achieved in 183 of the 196 CFA access sites (93.4%), and was specifically 85.9% and 98.3% for sheaths ≥20Fr and ≤18Fr respectively. There were 13 periprocedural complications (bleeding = 10, arterial dissection and thrombosis = 1, pseudoaneurysm = 2) all leading to OC. Use of ≥20Fr sheaths had significantly higher OC rate (P < .05). Reconstruction was achieved with primary repair (N = 11) and patch angioplasty (N = 2). Mean hospital stay was 1.8 days. The literature review (vascular closure of 2921 CFA access sites) revealed an overall technical success rate of 92.3%. Device related- were more common than patient related-OCs (P < .05). p-EVAR procedures are safe and feasible. Sheath size is a significant predictor of OC rate and more OCs might be expected with very large (≥20Fr) sheath sizes.  相似文献   
174.
The development of heart failure in patients with aortic valve disease is associated with increased mortality, unless aortic valve replacement is performed. There is an especially high risk of death among patients with low ejection fraction. The heart failure must be treated and the patient’s condition stabilized before surgery is performed. A delay in surgery, on the other hand, may lead to irreversible cardiac dysfunction and culminate in heart failure. Initial management must include an evaluation of the severity of the lesion and the functional state of the left ventricle. It is possible to achieve both of these goals simultaneously with echocardiography and pharmacologic challenge.  相似文献   
175.
A variety of statistical methods can be used to analyze the results of heart valve replacement. In this review, we illustrate the methodology and the application of the techniques that are most widely used. For early events, univariate analysis and multivariate logistic regression are illustrated. For late (time-related) events, nonparametric methods (Kaplan–Meier and cumulative incidence or ‘actual’ analysis), parametric methods (based on the exponential, Gompertz and Weibull distributions) and semiparametric methods (Cox proportional hazards) are illustrated.  相似文献   
176.
Heart failure is a clinical syndrome with significant morbidity and mortality. The use of left ventricular assist devices has improved outcomes for patients with advanced heart failure in the face of limited donor organs available for heart transplantation. This article describes current issues and limitations facing the left ventricular assist device field and explores how the field can be expanded in this setting.  相似文献   
177.
Obstructive lesions in the aortic arch are comprised of discrete coarctation, tubular hypoplasia and interruption. This review discusses the anatomy of the lesions relevant to interventional treatment. Catheter intervention, using not only balloon angioplasty but also stent implantation for coarctation, has been developed over the past couple of decades as an alternative treatment to surgery. Several studies have reported long-term outcome and the benefits of surgery and catheter intervention for treating obstructive lesions in the aortic arch but more studies are needed for comparable evaluations. The development of imaging and further improvement of surgical and catheter intervention, such as hybrid intervention or new devices, will help in removing the obstruction safely.  相似文献   
178.
Supravalvar aortic stenosis (SVAS) is a congenital anomaly characterized by a discrete or diffuse narrowing of the ascending aorta. It may also be associated with right-ventricular outflow tract obstruction, aortic valve pathology and coronary ostial stenosis. While present in both familial and sporadic forms, it demonstrates a strong association with William–Beuren syndrome, both being anomalies associated with defects in the elastin gene. In this article, the authors have discussed the etiology, morphology, clinical presentation and genetic basis of SVAS. Various surgical approaches, both conventional and recent, have been discussed and demonstrated with the aid of diagrams. Single-, two- and three-sinus methods have been presented, along with a comparative analysis of early results, associated procedures, late mortality and reoperation. In conclusion, the authors have described their institutional experience of more than 40 years in the surgical management of SVAS.  相似文献   
179.
Pregnancy causes a significant and sustained increase in cardiac output that may be poorly tolerated in cases of underlying heart disease. Valvular stenosis is often poorly tolerated and may require intervention during pregnancy, percutaneous intervention being the favored option. Conversely, regurgitant valve diseases are generally well-tolerated. Pregnancy in patients who have previously undergone prosthetic valve replacement raises specific problems linked to anticoagulant therapy. The choice is difficult between oral anticoagulation, which carries a risk of embryopathy, and heparin therapy, which is safer for the fetus but is associated with a high thromboembolic risk for the mother. The diversity of cases highlights the need for appropriate evaluation of heart disease before pregnancy and close follow-up by specialized teams.  相似文献   
180.
Patent foramen ovale is incriminated in patients with cryptogenic stroke; however, concrete evidence that closure of patent foramen ovale using various devices is superior to continued medical therapy is not yet available. Controlled randomized trials are well underway to address this issue.  相似文献   
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