is a procedure used to diagnose or treat conditions of the coronary arteries by threading a catheter (long tube) from a leg artery into a coronary artery.

The procedure described is coronary catheterization: a catheter is threaded through an artery, often from the leg, to reach the coronary arteries for diagnosis or treatment. An angiogram is an imaging test that may be performed during catheterization, but it is not the broader procedure described.

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