For that reason, babies with l-TGA usually won't have any obvious symptoms at birth.

正个原因，患有L-TGA宝宝在出生时没有明状。

So transposition of the great arteries, or TGA —you might be able to guess— is when these two arteries swap locations.

所以大动脉转位（TGA），顾名思义，就指两个动脉交换了位置。

Ultimately the cause of TGA is unknown, but there are diseases and behaviors that are associated with higher risk of babies having TGA.

TGA病因目前未知，但有很多疾病和行为婴幼儿患TGA高危因素。

So in this case, unlike d-TGA, circulation is preserved and therefore sometimes this is called congenitally corrected TGA.

所以不像d-TGA，在种情况下，正常循环被保留了下来，因此有时候又被称为先天矫正TGA。

This essentially means that d-TGA leads to death unless there is some way for blood between the pulmonary and systemic circulations to mix.

就意味着，除非有一种方法可以将肺循环和全身循环混合，否则d-TGA会导致死亡。

If the shunt is large enough such that the initial symptoms aren't noticed and the TGA isn't repaired, the heart can progress to congestive heart failure.

如果分流足够大使得最初状没被发现且TGA没有修复，就会发展为充性心力衰竭。

Less commonly, babies can have levo-transposition of the great arteries, or l-TGA, with levo meaning that the aorta's primarily to the " left" of the pulmonary artery.

更少见地，宝宝可能会有左旋-大动脉转位，即L-TGA，左旋意思主动脉主要位于肺动脉左侧。

This isn't good, and this situation is actually called complete TGA, or sometimes dextro-TGA or d-TGA, dextro meaning " right" , since in this case, the aorta's in front of and primarily to the right of the pulmonary artery.

种情况不太妙，被称为完全TGA，有时也叫右旋TGA或者d-TGA，dextro意思右旋，因为种情况下，主动脉在肺动脉前面并且主要在肺动脉右边。