左心房和心耳部自发超声造影现象的血流动力学状态及其意义

Blood Flow Dynamics and Its Significance of Spontaneous Echo Contrast in Left Atrium and Left Atrial Appendage

采用双平面经食管超声心动图观察分析了１２０例受检者左房及其耳部自发超声造影（ＳＥＣ）现象的血流动力学状态及有关因素．结果表明，ＳＥＣ的发生率占受检人数的３７．５％．在二尖瓣狭窄患者则高达８０％．在ＳＥＣ阳性组，房颤，血栓和／或栓塞的发生率明显高于ＳＥＣ阴性组，且其左房内径明显增大，心耳内血流速度则显著减慢．相关及回归分析发现，心耳内的负向血流速度与ＳＥＣ的产生具有最高的相关性．而ＳＥＣ、房颤则与血栓和／或栓塞显著相关．结论：①左房及其耳部ＳＥＣ最常见于二尖瓣狭窄；②左房扩大及房颤是产生ＳＥＣ的环境条件，而左房功能减退，血流缓慢或淤滞则是造成ＳＥＣ的主要原因；③ＳＥＣ现象是血栓形成和／或栓塞的独立预报因子，在伴有房颤的情况下，血栓和／或栓塞的危险性将大大增加．

This study investigated the blood flow dynamics and related factors of spontaneous echo contrast (SEC) in left atrium (LA) and left atrial appendage (LAA)in 120 patients using biplane transesophageal echocardiography. The results showed that SEC was found in 37. 5% of 120 patients, 80% of which seen in 45 patients with mitral stenosis(MS),and that negative flow velocity in LAA had the strongest correlation to SEC, while SEC,atrial fibrillation (AF)were independent predictive factors for the development of thrombus within LA and LAA.Meanwhile,in patients with SEC the incidence of AF and thromboembolism were much more common,and the dimension of LA was increased,while the flow velocity in LAA decreased significantly than that of those without SEC.So,it was concluded that ① SEC within LA and LAA was most common in patients with MS;②Dilation of LA and AF were important conditions for developing SEC.while slowly blood flow or blood stasis within LA and LAA, or dysfunction of LA and LAA were the main determinants for the formation of SEC;③ SEC was an independent predictive factor for the development of thrombus in LA or LAA,or for cardiogenic embolic events.