And she's really gonna thread a catheter up my leg, all the way to my heart?

她要从我腿部插导管进去 直通心脏?

And what doctors do is they insert a small tube called a catheter usually in a blood vessel in the groin and thread it up into the kidney in this case.

医生将小导管插入腹股沟处的一根血管，然后将导管插至肾脏。