Su P, McCarthy K P, Ho S Y
National Heart and Lung Institute, Imperial College, Guy Scadding Building, Dovehouse Street, London SW3 6LY, UK.
Heart. 2008 Sep;94(9):1166-70. doi: 10.1136/hrt.2006.111989. Epub 2007 May 8.
Occlusion of the left atrial appendage (LAA) is thought to reduce the risk of thromboembolic events in patients with atrial fibrillation.
To examine the LAA and its relationship to neighbouring structures that may be put at risk when intervening to occlude its os.
31 heart specimens were examined grossly. Four of the LAAs were processed for histological examination and endocasts were made from 11 appendages. The diameters of the LAA os and proximity to the left superior pulmonary vein, mitral valve and left anterior descending artery were measured and areas of thin atrial wall in the vicinity were noted.
The LAA orifice was oval shaped in all cases with a mean (SD) diameter of 17.4 (4) mm (range 10-24.1). The mean (SD) distances of the LAA orifice to the left superior pulmonary vein and mitral valve were 11.1 (4.1) mm and 10.7 (2.4) mm, respectively. The left anterior descending, circumflex artery and, in 6 cases, the sinus node artery, were in close proximity to the LAA. Pits or troughs and areas of thin atrial wall were found in 57.7% of hearts within a 20.9 mm radius from the os. Histology showed small crevices and areas of very thin wall within the trabeculated appendage.
The LAA orifice is oval shaped and thin areas of appendage wall and atrial wall are common. Potentially, the left superior pulmonary vein, mitral valve and anterior descending coronary artery can be at risk during occlusion of the os.
左心耳（LAA）封堵被认为可降低心房颤动患者发生血栓栓塞事件的风险。
研究左心耳及其与邻近结构的关系，这些结构在封堵左心耳开口时可能会受到影响。
对31个心脏标本进行大体检查。对其中4个左心耳进行组织学检查，并对11个心耳制作铸型。测量左心耳开口的直径以及与左上肺静脉、二尖瓣和左前降支动脉的距离，并记录附近心房壁薄的区域。
所有病例中左心耳开口均呈椭圆形，平均（标准差）直径为17.4（4）mm（范围10 - 24.1）。左心耳开口与左上肺静脉和二尖瓣的平均（标准差）距离分别为11.1（4.1）mm和10.7（2.4）mm。左前降支、回旋支动脉，以及6例中的窦房结动脉，均与左心耳紧邻。在距开口半径20.9 mm范围内，57.7%的心脏中发现有凹坑或沟以及心房壁薄的区域。组织学显示小梁状心耳内有小裂缝和非常薄的壁区域。
左心耳开口呈椭圆形，心耳壁和心房壁的薄区域很常见。在封堵开口过程中，左上肺静脉、二尖瓣和冠状动脉前降支可能会受到影响。
