[OJFord]

In medicine/surgery, 'invasive' is a bit of a term of art, meaning that implements physically enter the body. 'keyhole surgery' (a small incision with a scope and tiny tooling pushed through) for example is often described as 'minimally invasive'.

[FireBeyond]

Yes. Even placing stents during cardiac catheterization (PCIs or angioplasty) is 'minimally invasive' because typically access is achieved by the femoral artery and snaked up (the femoral comes "direct" from the heart, for all intents).

Yes, you blow up vessels with a balloon and leave a metal sheath in them, but as you say, minimally invasive, because you didn't crack the chest to do it.