Physiological function of left atrial appendage

Regulation of pressure and volume load: There are thick comb muscles in LAA, whose characteristics are similar to those of ventricular muscle cells and skeletal muscle cells. 4. Therefore, the active contraction function and compliance of LAA are much stronger than the rest of LA. Hemodynamic examination during surgery showed that clamping LAA could lead to an increase in immediate LA mean pressure and diastolic blood flow velocity of mitral valve orifice and pulmonary vein orifice. Therefore, when LA pressure and volume load increase, LAA plays an important role in regulating its hemodynamics.

Simply understand what is left atrial appendage

The protruding part of the left atrium in the front right direction is called the left atrial appendage. There is no obvious boundary between this part and this part of the atrium, but the inner wall of the atrium is smooth, and the comb muscle of the inner wall of the auricle is developed but not smooth.

Clinical significance of intracardiac shunt

The difference of blood oxygen content in the right cardiac cavity exceeds the reference value, indicating that there is left-to-right shunt. Left to right shunt>50% should be operated or occluded in time. The decrease of arterial blood oxygen content indicates right-to-left shunt, which is commonly seen in tetralogy of Fallot, transposition of great arteries, and Eisenmenger syndrome. Cyanotic congenital heart disease with right-to-left shunt should be evaluated for malformation, and a reasonable surgical plan and scheme should be formulated in time. If Eisenmenger syndrome has occurred, the surgical opportunity will be lost.