1509
The left atrial appendage (LAA) is derived from the left wall of the primary atrium, which forms during the fourth week of embryonic development.
It lies within the confines of the pericardium in close relation to the free wall of the left ventricle and thus its emptying and filling may be significantly affected by left ventricular function.
Functions as a decompression chamber during left ventricular systole and during other periods when left atrial pressure is high.
Has a high concentration of atrial natriuretic factor (ANF) granules.
The LAA has a role in thirst regulation and water retention because it is an important source of atrial natriuretic factor.
The left atrial appendage has been implicated is a major source of emboli in more than 90% of ischemic strokes
Thrombus Likely to form in the LAA in patients with atrial fibrillation and mitral valve disease.
Obliteration or amputation of the LAA may help to reduce the risk of thromboembolism.
Most thrombi in atrial fibrillation arise in the left atrial appendage.
Percutaneous left atrial appendage ligation as an adjunct to pulmonary vein isolation did not increase freedom from atrial arrhythmias at 12 months compared with pulmonary vein isolation alone in patients with with non-paroxysmal atrial fibrillation. (aMAZE, investigators).