左心耳形态结构和功能与心房颤动相关性脑卒中的研究和展望

心房颤动（简称房颤）是临床最常见的持续性心律失常,房颤患者缺血性脑卒中的风险较非房颤患者明显增高,而其血栓主要来源于左心耳（LAA）。长期以来,非瓣膜性房颤患者的抗凝原则主要依据CHA2DS2-VASC评分,但是对于中低危患者存在局限性。随着医学影像学的发展,学者们发现左心耳形态结构特征和功能参数与血栓形成有关,可潜在地用于预测房颤脑卒中的发生。故本文拟对此进行综述,以期为下一步研究提供思路。     

Fermeture d’auricule et pathologie embolique

Atrial fibrillation (AF) is frequent and responsible for embolic events. Currently, the gold standard to prevent such embolic events is anticoagulant therapy with vitamin K antagonist (VKA) or direct oral anticoagulant in nonvalvular AF. Recently, left atrial appendage closure was proposed as an alternative to anticoagulant inpatient with high embolic risk and contraindication to anticoagulant therapy. Data from randomized trials were consistent with a non-inferiority of left atrial appendage closure in comparison to VKA in terms of stroke and cardiovascular death. However, despite improvements in procedure results and complications reduction, this invasive strategy has to be performed with optimal security as this strategy is a preventive treatment in high-risk patients. These improvements may allow an extension of indications of left atrial appendage closure to lower profile risk patients as an alternative to anticoagulant. Indeed, anticoagulant is a risky therapy with hemorrhagic events and observance is a real issue in an asymptomatic population. Finally, there is a lack of data in recent literature comparing left atrial appendage closure to direct oral anticoagulant, widely used in daily practice, as well as cost-effectiveness of this procedure in comparison to anticoagulant.     

Analysis of <Emphasis Type="Italic">in vivo</Emphasis> left atrial appendage morphology in patients with atrial fibrillation: a direct comparison of transesophageal echocardiography,planar cardiac CT,and segmented three-dimensional cardiac CT

Purpose  Recent development of percutaneous left atrial appendage (LAA) occlusion devices has underscored the need for an accurate understanding of LAA morphology and the interchangeability of results from differing imaging modalities. The purpose of this study is to assess LAA morphology and location in AF patients, directly comparing transesophageal echocardiography (TEE), planar cardiac computed tomography (CT), and three-dimensional segmented CT reconstructions. Methods  Fifty-three patients underwent adequate TEE and cardiac CT. Quantitative measurements of maximal LAA orifice diameters, widths, and depths were obtained from each imaging modality. Left atrial and LAA volumes were measured using segmented CT. Results  The mean LAA orifice diameter for segmented CT, planar CT, and TEE was 28.5 ± 4.5, 26.3 ± 4.1, and 26.1 ± 6.4 mm, respectively. Conclusions  LAA orifice measurements among these imaging modalities are not interchangeable. This difference may be clinically significant because of the need for accurate sizing of LAA occlusion devices. Use of preprocedural segmented CT may improve initial device sizing.     

An overview of current and emerging devices for percutaneous left atrial appendage closure

Atrial fibrillation (AF) is common and is a prominent risk factor for ischemic stroke. Oral anticoagulant (OAC) therapy has been the main strategy for stroke prevention in AF patients; however, OAC therapy carries a bleeding risk and is not tolerated by all patients. Left atrial appendage (LAA) closure offers a non-pharmacological alternative for stroke prevention in patients with non-valvular AF. In this update, an overview of current and emerging LAA occluders is given – with special attention to the key design features of every single device and, if available, preclinical or clinical data.     

Congenital absence of left atrial appendage: A case report and literature review

Congenital absence of left atrial appendage (LAA) is an extremely rare entity. A 50-year-old man with no past cardiac history was admitted with symptomatic atrial fibrillation (AF). Before subjecting him to direct current (DC) cardioversion, the patient underwent a transesophageal echocardiography (TEE) examination, but neither LAA nor a cardiac thrombus could be detected. Absence of both was confirmed by cardiac computer tomography (CT) and a cardiac magnetic resonance imaging (MRI) scan. The patient reverted to sinus rhythm with an uneventful synchronized biphasic DC shock of 100 joules.