Objective To compare the curative effect of PDA surgical ligation between left Ausculatry triangle thoracotomy ( ATT ) and Posterolateral incision ( PLT ) .

目的评估左听诊 三角切口（ATT）与后外侧切口（PLT）下动脉导管未闭（PDA）缝扎 术的疗效。

Three pillars nailing the arrangement surgical cannulated screw more the traditional form three root nail group chooses the arrangement pour triangle improved three pillars nailing group chose the distribution of longitudinal arrangement way .

三根钉 手术空心钉的排列形态比较多，传统三根钉组选用倒 三角形的排列方式，改良三根钉组选择了纵向排列的分布方式。