What is the surgery called for clogged arteries?

Angioplasty - Bypass: In angioplasty (potentially less invasive) a thin, high tensile strength folded plastic balloon (with or without a stent) is passed into narrowings & hydraulically inflated using pressures 50 to 250 x's arterial pressure to expand the narrowing. In bypass surgery (more invasive) another vessel (commonly a vein) is sewn into an artery prior to a narrowing and again downstream from the narrowing.